The effect of olivocochlear bundle transection on tuning curves and acoustic distortion products. A growing body of research suggests that the efferent innervation to the cochlea, the olivocochlear bundle (OCB), may modulate the mechanical function of the cochlea. However, the role of tonic OCB input in cochlear function remains poorly understood. The purpose of this study was to determine the influence of tonic efferent input on cochlear mechanics, by transecting the entire OCB in guinea pigs, and observing changes in tuning curves and acoustic distortion products. The OCB was transected by avulsing the inferior vestibular nerve as it enters the internal auditory canal of the right bulla. Auditory brainstem response (ABR) thresholds, ABR tuning curves, and acoustic distortion products were measured before and after surgery. Successful transection of the OCB was verified histochemically. Results revealed no consistent changes in tuning curves or in the growth functions of the distortion products. To the extent that these measures reflect cochlear mechanical nonlinearities, it is concluded that tonic OCB input is not necessary for grossly normal cochlear mechanical function in the 10-kHz region of the guinea pig cochlea. It thus seems unlikely that the efferents are involved in establishing a "set point" for cochlear operation.


Directional dependence of auditory sensitivity and frequency selectivity in the leopard frog. Direction-dependent changes in frequency selectivity were documented in three populations of neurons in the auditory periphery of the leopard frog: low-, mid-, and high-frequency sensitive fibers. These changes were most pronounced in the mid-frequency (720-1199 Hz) sensitive fibers which exhibited positive shifts in characteristic frequencies (CFs) and concomitant narrowed bandwidths from posterior speaker presentations. Maximum sensitivities were observed for ipsilateral speaker presentations in these fibers. Low-frequency (63-500 Hz) sensitive fibers exhibited mean threshold shifts at their CFs of up to -7 dB with posterior speaker presentations. Low- and high-frequency sensitive fibers whose CFs closely correspond to the peaks of spectral energy of the species' mating call were the most sensitive (exhibited lowest thresholds) but showed little directional-dependent frequency selectivity. Directional-dependent variation in frequency selectivity and sensitivity in low- and mid-frequency sensitive fibers was attributed to pressure and phase differences impinging on the inner surface of the eardrum.


Controversies in nursing ethics: a historical review. The author critiques the dialectic between justice-based ethics and an ethic of caring from a historical perspective (by analogy with the dialectic between agape and friendship). Justice-based ethics have been problematic for nursing because of the decontextualized approach. The ethic of caring is problematic because caring, being contextual, is particularistic and therefore can be based on morally irrelevant factors, such as liking. There is a tradition of writing which seeks to reconcile the particularistic obligations of friendship with the moral duty to all others equally. Ideas from the following authors are reviewed for relevance to nursing: Aristotle, Aelred of Rievaulx, Augustine, John Cassian, Cicero, George Berkeley, Immanuel Kant, Michel de Montaigne, Jeremy Taylor and Max Weber. The authors concludes by noting that both sides of the dialectic are synthesized in the lived experience of individuals. A synthesis in thought is called for on this basis.


Ethical reasoning in nurses' and physicians' stories about care episodes. Twenty-three registered nurses and nine physicians reported 43 stories about ethically difficult care situations. Themes in nurses' and physicians' stories were described by means of narrative ethical theory. It turned out that nurses and physicians related different kinds of stories. They also seemed to use different kinds of ethical reasoning. This result was interpreted as mainly connected to the fact that the two professions have different tasks to accomplish and are trained in disciplines with different foci; nursing and medicine. The need to find a common frame story covering the two professional stories was stressed.


Ethical challenge in community health nursing. Community health nurses frequently face situations involving ethical conflicts, but little research has been carried out in this area. This paper, based on a study of dilemmas defined by 30 practising community health nurses in urban and rural British Columbia, Canada, presents an analysis of the situations that contain the most serious ethical conflicts for nurses working in the community. Although issues related to client's rights, nurses' interactions with colleagues and the system, and nurses' rights were explored, nurses in the study reported that situations involving high-risk parenting provided the most serious ethical challenges. Strategies to help nurses caring for such vulnerable clients are described. As well, this paper offers some discussion on implications for community health nursing practice and education in light of current changes and challenges.


From helper to human: a reconceptualization of the nurse as person. This paper explores the nature of the nurse as person, as represented by nursing literature and in the author's own research, by considering the tendency nurses have to perceive as different the characteristics of nurses and patients as human beings. Nursing scholars have tended to categorize nurses and patients into discrete 'compartments' that are convenient for descriptive purposes, but nevertheless have had a tendency to limit people's essential humanness. The metaparadigm concept of person in nursing can take on a different meaning if people are regarded in terms of their oneness, rather than by their separateness. A brief introduction will be given to some meanings generated in some nursing research, which described the effects of ordinariness as they were manifested by nurses and patients in everyday nursing unit life. The possibility is raised that a reconceptualization of the nurse could describe the nurse, not only as a professional helper, but also as a human, whose effectiveness is enhanced through a sense of shared humanity with patients.


Reducing distress during abortion: a test of sensory information. The purpose of this study was to examine the effect of providing sensory information on distress during first-trimester abortion using a 2 x 2 factorial design. The factors were type of information given and type of anaesthesia used. Eighty-four women completed pre-abortion measures of state anxiety, and subjective pain and distress. Post-abortion measures included behavioural distress, subjective distress, pain and state anxiety. No significant differences were found for type of information (sensory vs. general) received on subjective or behavioural distress measures. Women receiving intravenous sedation together with local cervical block reported less subjective distress and pain than women receiving local anaesthesia alone. Sensory information was not effective in reducing distress during abortion.


Stress, alcohol, tobacco and illicit drug use amongst nurses: a Scottish study. This paper examines levels of stress amongst a representative sample of 600 qualified nurses in the Lothian Region of Scotland. The results indicated a number of significant variations in the patterns of stress amongst different subgroups of nurses. The highest stress levels amongst females were evident amongst medical nurses while the lowest levels were reported by those in psychiatry. No comparable differences were evident amongst males in different fields of nursing. Stress was also associated with the use of alcohol, but not with tobacco smoking. Illicit drug use was associated with stress amongst females. Amongst both males and females the variable most predictive of stress was concern about AIDS. Amongst females, administrative workload was an equally important predictor. It is concluded that as the HIV/AIDS epidemic spreads efforts will be needed to support nursing staff and to reduce stress levels.


Acquired immunodeficiency syndrome: knowledge and attitudes of nurses in Northern Ireland. The number of people suffering from conditions associated with HIV infection is growing steadily. These people require care from nurses who should be well trained to undertake all the various aspects of nursing care. Surveys have indicated that health professionals associate AIDS with minority groups such as homosexuals, drug-abusers and prostitutes. Incidents of sub-optimal nursing care of AIDS patients, or suspected AIDS patients belonging to these minority groups, have been well documented. Surveys have revealed much ignorance and confusion among the general public as well as among health professionals with regard to this controversial syndrome. This study aimed to measure nurses' knowledge and attitudes towards homosexuals, drug-abusers and prostitutes, who through their lifestyle are at increased risk for HIV infection. Questionnaires were distributed to a random sample of 800 nurses in Northern Ireland. The sample was stratified by several demographic variables. A response rate of almost 60% was achieved. Nurses appeared to have a moderate knowledge of issues related to HIV infection, but there were large gaps in their knowledge of the terminology used in HIV infection. Nurses were not extremely worried about AIDS itself. However, homosexuals, prostitutes and drug-abusers were seen to be at least partly responsible for their own illness. Implications for nursing care and for nurse education are discussed.


Caring in the preparation of long-term psychiatric patients for non-institutional care: ethnonursing study. Caring is the central and unifying domain for the body of knowledge and practices in nursing. It was the purpose of this ethnonursing study to describe caring in the residential training for long-term psychiatric patients in Finland in 1977-1988. Data were collected by interviewing 20 patients and 11 members of staff. On the basis of the empirical data, four stages of caring could be distinguished: formation, reformation, fragmentation and reintegration. The changes in caring occurred on the following dimensions: work for wages vs. vocation; spontaneous social interaction vs. the systematic instruction of practical skills; and collective activities vs. individual activities.


On laying the foundations for an empirico-logical model of mental health nursing. This paper argues that nursing is an elemental activity, the first concern of which is a person's experience of illness, not the causes of that experience. Any model of nursing should begin with an account of that experience and deduce from that what it is that nurses ought to do in order to explain what it is that they actually do. The logical form of such a model is delineated. An account of the experience of illness is offered and the nursing imperatives implied by such an account are stated in terms of securing client safety, obviating the client's experience by treatment and motivating the client to sustain or resume ordinary activities of life. These dimensions of nursing care--safety, treatment and motivation--were tested against the actual activities of mental health nurses in three services and were found to have utility as categories of nursing activity. A summary of that research is given and an outline of a model of mental health nursing suggested by the results is given.


Case management in community care: concepts, practices and implications for nursing. Case management has recently become a prominent issue in British community policy and practice, but one which, at the same time, has been subjected to a variety of interpretations. For this reason, it is considered useful to analyse it in terms of a framework embracing conceptual and operational components rather than within the more limiting confines of conventional definitions. A review, within this framework, of initial research projects suggests case management to be a viable mode of community care, with generally favourable outcomes. It also suggests a potentially significant role for community nurses as case managers, although several issues need to be considered when implementing these practices. Finally, a number of questions emerge which should be the focus of future research in the area.


Long-term care personnel assess their attitudes and knowledge of the older adult. The purpose of this study was to compare long-term care employees' attitude and knowledge about myths of ageing and normal age changes, before and after exposure to formal educational sessions. The researchers investigated if there was a difference in knowledge level and change in attitudes of long-term care employees after educational sessions. The subjects for this study were defined as persons who had any contact with the residents at St Charles Care Center. The final data set used in the analysis contained 84 observations. Each participant attended three 1-hour classes which consisted of simulation of handicaps, normal age-related changes, and myths and realities of ageing. Overall, there was a significant increase in knowledge from the pre-test to the post-test. The study also tested for a negative (anti-aged) bias attitude and a positive (falsely pro-aged) bias attitude among the individuals. At the end of the study there was still a slight negative biased attitude towards ageing. The data suggest that continuing education is an effective means of influencing the knowledge and attitudes of personnel in long-term care facilities. Recommendation for future research should be that this study be replicated in another long-term care facility with the addition of a job satisfaction tool.


Life history: a qualitative method of research. The life-history method of qualitative research is an alternative to empirical methods for identifying and documenting health patterns of individuals and groups. It allows the nurse researcher to explore a person's microhistorical (individual) experiences within a macrohistorical (history of the time) framework. Life-history information challenges the nurse to understand an individual's current attitudes and behaviours and how they may have been influenced by initial decisions made at another time and in another place. This paper describes a new direction in nursing research and identifies specific steps for using the life-history approach.


Continuing professional education for qualified nurses: a review of the literature. Reviewed literature identifies the importance of continuing professional education and professional development for nurses subsequent to initial registration (including enrolled nurses). However, there is a lack of empirically based work analysing nurses' perceptions of their continuing professional education needs and the perceived outcomes of continuing professional education in terms of changes in knowledge accretion, attitudes, skills, job satisfaction, staff retention and career development. It is suggested that this lack of empirical work needs to be addressed if the proposed plans of the United Kingdom Council for Nursing, Midwifery and Health Visiting (UKCC) to introduce mandatory continuing professional education are to have maximum benefits for clients, nurses and the service.


The perception of time as a factor in Rogers' Science of Unitary Human Beings: a literature review. This literature review examines an operationalization of Martha Rogers' Science of Unitary Human Beings. The principle of helicy and the theory of accelerating evolution has been used by a number of authors as a theoretical framework for the exploration of how patients, particularly those who are elderly, perceive the passage of time. Although there is no conclusive evidence to support the aspect of Rogers' theory of accelerating evolution that suggests that as people grow older they perceive time as passing more quickly, there is evidence that suggests that different elderly patients can have a variable perception of the passage of time. For example, some patients perceive the passage of time as rapid and will be happy to sit quietly. Others may perceive the passage of time as occurring more slowly and will require diversional therapy. A conclusion is reached that nurses should include individual assessments of the patients' perception of the passage of time in order to identify accurately the degree of need for diversional activities.


Faculty research productivity and organizational structure in schools of nursing. The purpose of this study was to identify the relationship between faculty research productivity and organizational structure in schools of nursing. The need for nursing research has been widely recognized by members of the nursing profession, yet comparatively few engage in conducting research. Although contextual variables have been investigated that facilitate or inhibit nursing research, the relationship between organizational structure and nursing research productivity has not been examined. This problem was examined within the context of the Entrepreneurial Theory of Formal Organizations. A survey methodology was used for data collection. Data on individual faculty research productivity and organizational structure in the school of nursing were obtained through the use of a questionnaire. A random sample of 300 faculty teaching in 60 master's and doctoral nursing schools in the United States was used. The instruments for data collection were Wakefield-Fisher's Adapted Scholarly Productivity Index and Hall's Organizational Inventory. The data were analyzed using Pearson Product-Moment Correlation Coefficients and multiple correlation/regression techniques. The overall relationship between faculty research productivity and organizational structure in schools of nursing was not significant at the .002 level of confidence. Although statistically significant relationships were not identified, scholarly research productivity and its subscale prepublication and research activities tended to vary positively with procedural specifications in a highly bureaucratic organizational structure. Further research may focus on identification of structural variables that support highly productive nurse researchers.


Nursing faculty practice: an organizational perspective. After reviewing the faculty practice literature of the 1980s and finding philosophical support for practice but also growing concerns about faculty role overload, the authors report a study to identify organizational factors that influence the role expectations of faculty members about practice. A survey was sent to the deans or directors of all National League for Nursing--accredited baccalaureate nursing programs (n = 462). Of the 356 respondents (78 per cent), 224 (63.3 per cent) reported that their school had practicing faculty, but only 20 schools (8.8 per cent) required practice. Written faculty practice plans were reported by 23 schools (10.2 per cent), and nursing centers by 41 schools. Thirty-six respondents (16 per cent) reported that practicing faculty generated revenue for the school. Practice was required for promotion in 15.8 per cent and for tenure in 15.3 per cent of all schools surveyed. The study showed significant direct relationships between master's and doctoral programs and practicing faculty, but there was an inverse relationship between the presence of a health science center and schools with practicing faculty. Organizational factors relating to both the number and per cent of faculty who practiced included requiring practice, having a practice plan, and having practice as a criterion for promotion and for tenure. Revenue generation and presence of formalized practice arrangements were related to the number of faculty who practiced but not the per cent of the total faculty who practiced. The study's findings have implications for nursing education in designing organizational structures and rewards that support faculty practice.


Nursing theory in nursing education: an educational imperative. Nursing has accepted theory as basic to its practice; however, the use and development of nursing theory is constrained by the approach used in nursing education. It is not appropriate or sufficient to isolate theory in one course. Moreover, confining nursing theory courses to graduate curricula, which is the custom in many schools of nursing, suggests that to focus on theory in the profession is esoteric. These curricular approaches inhibit socialization of students to the value of theory as essential to practice. It is imperative that nursing education engage students in theory-related content at all levels. This article presents a scheme to achieve systematic integration of theory-related content in curricula at all levels of nursing education from associate degree to doctorate. Through theory-based practice, nursing will come to realize its full potential as a discipline.


Distance learning: an innovative approach to nursing education. This article presents four views encompassing one nursing department's experience using distance learning technology. The challenge of presenting a nursing class through distance technology is discussed from the perspective of the telecommunication faculty providing the technological support, the nursing faculty teaching the on-campus course, the off-campus nursing faculty coordinating the course at the outreach site, and the head of the Department of Nursing. Review of course grades demonstrated that off-campus students achieved higher grades than on-campus students. All students evaluated the teacher as being effective; however, off-campus students were not as strong in their opinion.


Liberal and professional undergraduate nursing education: maintaining the connections. Current recommendations to improve undergraduate education range from increasing the proportion of general education credits to removing professional preparation from undergraduate education. The authors argue for the necessity of integrating general education and professional preparation throughout all levels of higher education. A conceptual framework to study professional preparation developed by Stark et al. is presented. Methods to integrate both general education and professional preparation are analyzed, and specific implications for nursing are discussed.


Preparing clinical preceptors to teach master's-level students in oncology nursing. This article reports the development of a structured program for clinical nurse specialists who served as clinical preceptors for graduate students in an oncology nursing program. A needs assessment of clinical preceptors was completed, and a program for the preceptors was developed based on the learning needs identified. In addition to the program, a Manual for Clinical Preceptors was developed. The benefits of this program include networking; positive working relationships among the preceptors, faculty, and students; potential job opportunities for students; potential applicants from the clinical agencies; and, ultimately, improved care for patients with cancer and their families. The authors conclude that administrators should support efforts to nurture and recognize the personnel in the clinical agencies.


Empowering the new graduate: a renewed professionalism for nursing. We are facing a crisis in nursing not unlike that faced by our foremothers and forefathers: a shortage of nurses that promises to get worse before it gets better. Attrition contributes to this shortage as does competition from other professions. Empowering our graduates is one solution to the crisis. Empowerment will enable us to retain persons in the profession as well as to attract new members. Providing graduates with a sense of the caring and scholarly heritage of the profession is part of that empowerment.


Nursing diagnoses: a study of cultural relevance. This study examines the adequacy/inadequacy of three nursing diagnoses with cultural etiologies: (1) impaired verbal communication related to cultural differences; (2) impaired social interaction related to sociocultural dissonance; and (3) noncompliance related to patient value system. The research tool was administered to the membership of the American Nurses Association Council on Cultural Diversity and the International Transcultural Nursing Society, with a response rate of N = 245 (42.2 per cent) from 43 states, the District of Columbia, and seven foreign countries. The tool listed the North American Nursing Diagnosis Association (NANDA) defining characteristics and cultural etiology for each diagnosis rated on a five-point Likert scale from "nearly always present" to "rarely present." The subjects also wrote and ranked other defining characteristics they used to make the diagnosis in clinical practice. Percentage distribution results indicate no defining characteristic meets the NANDA criteria for a major or minor defining characteristic. By collapsing categories, seven were acceptable only as minor defining characteristics. Respondents' 113 suggestions for additional characteristics were content analyzed. Themes for 12 categories were intuited and added to the lists. Based on respondents' suggestions, the definitions for each diagnosis were reworked, and new cultural-related factors were added. The cultural adequacy/inadequacy of elements within these three diagnoses was identified and provides the opportunity for greater selectivity in their clinical use. Additional suggestions from transcultural nursing experts form a data base for future research to expand the use of the currently limited components of NANDA diagnoses with culturally diverse patients.


Periodontal prosthesis: creating successful restorations. When the dentition is mutilated by periodontal disease, it's hard to restore. The authors outline the mechanical and biological problems to overcome in treating advanced periodontal disease.


Things your most satisfied patients won't tell you. In a competitive market, patient satisfaction is critical. The author surveyed patients and discusses several nontechnical factors that influence patient satisfaction.


Recent advances in periodontal diagnosis and treatment: exploring new treatment alternatives. A better understanding of the etiology and pathogenesis of periodontal diseases provides clinicians and researchers with a number of new diagnostic techniques and treatment alternatives. These new developments may also offer the clinician additional information for treatment planning.


Major psychological disorders in chronic TMD patients: implications for successful management. The authors assessed psychological disorders in 50 chronic TMD patients. These disorders appear to be a major concomitant factor in chronic TMD, and may need to be treated for successful outcomes.


Today's sonics: using the combined hand/sonic endodontic technique. Combing sonic technology with hand instrumentation facilitates root canal preparation. The authors present an efficient and safe technique.


Minocycline use discolors teeth.

Minocycline use discolors teeth. A 25-year-old woman with gray striated staining on all teeth took minocycline for two years. Staining corresponded with the treatment time.


Replanting avulsed primary teeth.

Replanting avulsed primary teeth. Tooth replantation is a viable procedure if performed under the following acceptable guidelines: Replant the tooth if time lapse is less than 30 minutes (a time lapse of more than one to two hours results in a poor prognosis); Transport the tooth or teeth in milk, saliva or blood; and Keep teeth and replant area clean to minimize infection. Quick action by the mother in bringing the child to the hospital emergency room was a vital first step. The fact that the child held the teeth in her mouth en route to the hospital--bathed in saliva and blood, still attached by the bit of gingival tissue in the warm mouth's environment--helped to contribute to a positive situation as well as did the good home care.


Oral health activities of U.S. children: results of a national health interview survey. Data from the 1989 National Health Interview Survey show oral health activities for U.S. children aged 2-17. Key population subgroups neither received optimal preventive care nor visited a dentist regularly.


Modifiers of timing and possible triggers of acute myocardial infarction in the Thrombolysis in Myocardial Infarction Phase II (TIMI II) Study Group. The aim of this study was to provide insight into the mechanism of acute myocardial infarction by determining the modifiers of timing and possible triggers of onset of infarction. A higher frequency of onset of acute myocardial infarction has been reported in the morning with a peak in the 1st 3 h after awakening. This observation suggests that the onset of infarction may be triggered by activity in the morning and at other times of the day. The clinical history of the 3,339 patients entered into the Thrombolysis in Myocardial Infarction phase II study was analyzed to determine characteristics predicting a higher frequency of infarction between 6 AM and noon, and onset of infarction during exertion. A higher proportion (34.4%) of infarctions began in the morning (6 AM to noon) compared with other times of the day. Characteristics independently predicting a higher frequency between 6 AM to noon were no beta-adrenergic blocking agent use in the 24 h before infarction, no discomfort other than the index pain in the preceding 48 h, occurrence of the infarction on a weekday and no history of current smoking. In 18.7% of patients, infarction occurred during moderate or marked physical activity. Independent predictors of exertion-related infarction included male gender, no history of current smoking, white race, no use of calcium channel blocking agents or nitrates in the preceding 24 h, the absence of either chest pain at rest in the 3 weeks before infarction or any pain in the preceding 48 h, the absence of new onset angina and the presence of exertional pain in the preceding 3 weeks. Compared with patients whose infarction occurred at rest or during mild activity, those with exertion-related infarction had fewer coronary vessels with > or = 60% stenosis (p = 0.002) and were more likely to have an occluded infarct-related vessel after thrombolytic therapy (p = 0.01). Further study of the timing and activity at onset of infarction may provide insight into the pathophysiologic mechanisms causing acute myocardial infarction and provide clues to preventive measures.


Effect of amiodarone on mortality after myocardial infarction: a double-blind, placebo-controlled, pilot study. The goal of this study was to evaluate the effect of amiodarone on mortality, ventricular arrhythmias and clinical complications in high risk postinfarction patients. No therapy has been shown to reduce sudden death in patients ineligible to receive beta-adrenergic blocking agents after myocardial infarction. Patients who were not eligible to receive beta-blockers were randomized to receive amiodarone (n = 305) or placebo (n = 308) for 1 year. There were 21 deaths in the amiodarone group compared with 33 in the placebo group (odds ratio 0.62, 95% confidence interval [CI] 0.35 to 1.08, p = 0.095). There were two noncardiac deaths in the amiodarone group and none in the placebo group; thus, the difference in cardiac mortality (19 vs. 33, respectively) was statistically significant (odds ratio 0.55, 95% CI 0.32 to 0.99, p = 0.048). There was a significant decrease in Lown class 4 ventricular arrhythmias (7.5% vs. 19.7%, respectively, p < 0.001). Adverse effects developed in 30% of amiodarone-treated patients and 10% of placebo-treated patients. Pulmonary toxicity, which was mild and reversible, occurred in only one patient in the amiodarone group but in no patient in the placebo group. This trial demonstrated a significant reduction in cardiac mortality and ventricular arrhythmias with amiodarone treatment. However, given the wide confidence intervals and borderline statistical significance of our trial, larger trials are needed to confirm or refute this view.


Benefits of intraoperative echocardiography in the surgical management of hypertrophic cardiomyopathy. The purpose of this study was to determine the role of intraoperative echocardiography in planning the site and extent of myectomy and in ensuring adequate control of the left ventricular outflow tract gradient. Although intraoperative echocardiography has been found to be beneficial in patients undergoing valve repair, its impact on surgical decisions in patients undergoing septal myectomy for hypertrophic cardiomyopathy has not been described. In 50 patients undergoing septal myectomy over a 5-year period, epicardial echocardiography was performed before cardiopulmonary bypass to establish the extent of outflow tract obstruction, locate its site and plan the myectomy. In 30 patients, transesophageal echocardiography was also used to corroborate data on outflow tract anatomy and examine the mitral valve. In 40 patients (80%) the initial myectomy resulted in a reduction of the maximal outflow tract gradient from 88 +/- 45 to 24 +/- 11 mm Hg, measured by epicardial continuous wave Doppler echocardiography. Ten patients (20%) were shown by postbypass intraoperative echocardiography to have an unsatisfactory result, based on a persistent gradient > 50 mm Hg (n = 7) or persistent mitral regurgitation of greater than moderate severity (n = 3). The postbypass two-dimensional echocardiogram was then used to direct the surgeon toward the most likely site of continued obstruction, and cardiopulmonary bypass was reinstituted to permit further myectomy (n = 9) or mitral valve repair (n = 1). After the second or subsequent period of cardiopulmonary bypass, the outflow tract gradient (26 +/- 14 mm Hg) was substantially reduced and was not significantly different from the postbypass gradient (24 +/- 11 mm Hg) in the group with initial surgical success. At postoperative follow-up (20 +/- 37 weeks), the maximal measured outflow tract gradient (22 +/- 21 mm Hg) showed no difference between patients with immediate surgical success and those requiring a second period of cardiopulmonary bypass for further resection. Intraoperative echocardiography proved a useful tool to guide the site and extent of septal myectomy, leading to more adequate surgical resection and to persistence of satisfactory control of the outflow tract obstruction into the early follow-up period.


Effect of progression of left ventricular hypertrophy on coronary artery dimensions in aortic valve disease. The effect of progression of left ventricular hypertrophy on coronary artery dimensions was studied in patients with aortic valve disease. Cross-sectional area of the left and right coronary arteries was determined by quantitative coronary arteriography in 12 control subjects and in 10 patients with aortic valve disease at baseline and after a follow-up period of 66 months. The cross-sectional area of the left coronary artery was larger in patients with aortic valve disease than in control subjects (left anterior descending artery 13 vs. 8 mm2, p < 0.001; left circumflex artery 13 vs. 6 mm2, p < 0.001). At the follow-up examination, cross-sectional area of the left coronary artery increased (left anterior descending artery 17 mm2, p < 0.01 vs. baseline; left circumflex artery 15 mm2, p < 0.01 vs. baseline). The cross-sectional area of the right coronary artery was not different in patients with aortic valve disease from that in control subjects. Left ventricular muscle mass was larger in patients with aortic valve disease both at baseline (269 g, p < 0.001) and after follow-up examination (339 g, p < 0.001) than in control subjects (136 g). The appropriateness of coronary artery size with respect to muscle mass was evaluated by normalizing cross-sectional area of the left coronary artery (left anterior descending plus left circumflex artery) per 100 g of left ventricular muscle mass (mm2/100 g). This index was 10.9 mm2/100 g in control subjects, and decreased in subjects with aortic valve disease from 10.3 mm2/100 g at baseline to 8.6 mm2/100 g at the follow-up measurement (p < 0.05 vs. control values). In patients with aortic valve disease, the progression of left ventricular hypertrophy is associated with an increase in left anterior descending and left circumflex coronary artery dimensions, whereas the size of the right coronary artery remains unchanged. Despite the enlargement of the left coronary artery, the cross-sectional area of the left coronary artery per 100 g of left ventricular muscle mass decreased. Hence, the increase in coronary artery size appears to be inadequate when the severity of left ventricular hypertrophy increases.


Left ventricular relaxation in dilated cardiomyopathy: relation to loading conditions and regional nonuniformity. The purpose of the present study was to investigate how loading conditions and regional nonuniformity affect left ventricular relaxation in dilated cardiomyopathy. Left ventricular relaxation is impaired in dilated cardiomyopathy. It has been suggested that relaxation abnormality is related to loading conditions and regional nonuniformity in the diseased heart. Left ventriculography with simultaneous pressure manometry was performed in 10 patients with dilated cardiomyopathy before and during nitroprusside infusion. Ten normal subjects served as a control group. Left ventricular hemodynamics, regional wall motion (assessed by the area method) and regional wall stress (Janz method) were analyzed. When compared with control subjects, the patients with dilated cardiomyopathy had a reduced left ventricular ejection fraction (p < 0.01) and prolonged relaxation time constants (p < 0.01). Left ventricular wall motion was both hypokinetic and asynchronous in the patient group. In addition, systolic regional wall stress was significantly greater, the time to peak wall stress was longer and the regional myocardial relaxation time constant was greater for each ventricular area assessed in the patient group (each p < 0.01). Administration of nitroprusside reduced left ventricular pressure and increased ejection fraction in the 10 patients with dilated cardiomyopathy. For each region, systolic regional wall stress and the time to peak wall stress decreased, and both regional hypokinesia and asynchrony lessened. These changes in loading conditions and regional nonuniformity were accompanied by an improvement in both regional and global ventricular relaxation that was significant, particularly during the early to midrelaxation phase when regional asynchrony was greatest. These results suggest that myocardial relaxation is sensitive to loading conditions and regional nonuniformity in dilated cardiomyopathy and that load reduction can improve both relaxation and systolic performance of the left ventricle.


Role of increases in heart rate in determining the occurrence and frequency of myocardial ischemia during daily life in patients with stable coronary artery disease. The goal of this study was to investigate the role of increases in heart rate in the development of ischemic episodes recorded during ambulatory electrocardiographic (ECG) monitoring in patients with stable coronary artery disease and to establish the importance of such increases in determining the frequency of ambulatory myocardial ischemia. The factors that determine the occurrence and frequency of episodes of myocardial ischemia that patients with stable coronary artery disease experience during daily life have not been clearly defined. In particular, the role of increases in heart rate in the development of myocardial ischemia is controversial. To address these issues, 54 patients (42 men and 12 women, mean age 60.5 +/- 8 years) with proved coronary artery disease who had > or = 1 mm ST segment depression during exercise testing underwent an exercise treadmill test with use of the National Institutes of Health combined protocol and a 48-h period of ambulatory ECG monitoring. The exercise ischemic threshold was determined as the heart rate at the onset of ST segment depression during exercise testing. During monitoring, 48 (89%) of the 54 patients had at least one episode of ST segment depression (mean +/- SD 6.6 +/- 5 episodes, range 0 to 22). The majority (320 of 359 or 89%) of ischemic episodes were preceded by an increase in heart rate > or = 10 beats/min; the most significant increase (22.3 +/- 10 beats/min) occurred during the 5-min period before the onset of the episode. An ischemic episode occurred 80% of the times the heart rate reached the exercise ischemic threshold. A strong correlation was observed between the number of times the exercise ischemic threshold was reached during monitoring and both the number and the duration of ischemic episodes (r = 0.90 and 0.71, respectively, p < 0.0001). Increases in heart rate that exceed the exercise ischemic threshold are commonly observed before the onset of episodes of ambulatory myocardial ischemia in patients with stable coronary artery disease. Moreover, such increases constitute an important determinant of the frequency of myocardial ischemia during daily life. These findings may explain the variability observed in the number of ischemic episodes and may have important implications for the mechanisms that contribute to myocardial ischemia in daily life and for the clinical evaluation of patients with coronary artery disease.


Long-term results of directional coronary atherectomy: predictors of restenosis. This study was performed to obtain better understanding of the long-term clinical efficacy of directional coronary atherectomy. Although this procedure yields favorable acute results, its acceptance has been limited by the perception that late results (that is, freedom from restenosis) are no better than those of conventional angioplasty. A total of 225 atherectomies performed in 190 patients between August 1988 and July 1991 were examined. Minimal lumen diameter of the treated segments was measured on angiograms obtained before, after and 6 months after intervention. Although most lesions (97%) had one or more characteristics predictive of unfavorable short- or long-term results after conventional angioplasty, atherectomy was successful in 205 lesions (91%) with a mean residual stenosis of 7 +/- 16%. After subsequent balloon angioplasty in 16 unsuccessful atherectomy attempts, procedural success was 98%. There were no deaths or Q wave myocardial infarctions, and one patient (0.5%) underwent emergency bypass surgery. Six-month angiographic follow-up was obtained in 77% of the eligible patients. The overall angiographic restenosis rate was 32%. Predictors of a lower restenosis rate included a postprocedure lumen diameter > 3 mm (24% vs. 39%, p = 0.047), serum cholesterol < or = 200 mg/dl (18% vs. 40%, p = 0.018) and recent myocardial infarction (16% vs. 37%, p = 0.034). Life-table analysis showed a 2% mortality rate and a 26% incidence of other events (myocardial infarction, repeat revascularization) within the 1st year. The annual 5% mortality rate and 7% incidence of other events during years 2 and 3 were related in large part to the existence or progression of disease at other locations. Six-month angiographic follow-up of patients who underwent directional coronary atherectomy during the 1st 3 years of our experience shows an overall restenosis rate of 32%, with lower rates in patients with a postatherectomy lumen diameter > or = 3 mm, cholesterol level < or = 200 mg/dl or a recent myocardial infarction. Few if any events relating to the site of atherectomy developed after the 1st year of follow-up.


Effect of age and coronary artery disease on response to snow shoveling. The objective of this study was to evaluate the effect of age and coronary artery disease on responses to snow shoveling. Little information is available on the hemodynamic and metabolic responses to snow shoveling. Sixteen men with asymptomatic coronary artery disease and relatively good functional work capacity, 13 older normal men and 12 younger normal men shoveled snow at a self-paced rate. Oxygen consumption, heart rate and blood pressure were determined. In nine men with coronary artery disease left ventricular ejection fraction was evaluated with an ambulatory radionuclide recorder. Oxygen consumption during snow shoveling differed (p < 0.05) among groups; it was lowest (18.5 +/- 0.8 ml/kg per min) in those with coronary artery disease, intermediate (22.2 +/- 0.9 ml/kg/min) in older normal men and highest (25.6 +/- 1.3 ml/kg/min) in younger normal men. Percent peak treadmill oxygen consumption and heart rate with shoveling in the three groups ranged from 60% to 68% and 75% to 78%, respectively. Left ventricular ejection fraction and frequency of arrhythmias during shoveling were similar to those during treadmill testing. During snow shoveling 1) the rate of energy expenditure selected varied in relation to each man's peak oxygen consumption; 2) older and younger normal men and asymptomatic men with coronary artery disease paced themselves at similar relative work intensities; 3) the work intensity selected represented hard work but was within commonly recommended criteria for aerobic exercise training; and 4) arrhythmias and left ventricular ejection fraction were similar to those associated with dynamic exercise.


Noninvasive definition of anatomic coronary artery disease by ultrafast computed tomographic scanning: a quantitative pathologic comparison study. The aim of this study was to determine the relation between coronary artery calcification detected by ultrafast computed tomographic scanning and histopathologic coronary artery disease. Recent studies suggest that discrete coronary artery calcification as visualized by ultrafast computed tomographic scanning may facilitate the noninvasive detection or estimation, or both, of the in situ extent of coronary disease. Such quantitative relations have not been established. Thirteen consecutive perfusion-fixed autopsy hearts (from eight male and five female patients aged 17 to 83 years) were scanned by ultrafast computed tomographic scanning in contiguous 3-mm tomographic sections. The major epicardial arteries were dissected free, positioned longitudinally and scanned again in cross section. Coronary artery calcification in a coronary segment was defined as the presence of one or more voxels with a computed tomographic density > 130 Hounsfield units. Each epicardial artery was sectioned longitudinally, stained and measured with a planimeter for quantification of cross-sectional and atherosclerotic plaque areas at 3-mm intervals, corresponding to the computed tomographic scans. A total of 522 paired coronary computed tomographic and histologic sections were studied. Direct relations were found between ultrafast computed tomographic scanning coronary artery calcium burden and atherosclerotic plaque area and percent lumen area stenosis. However, the range for plaque area or percent lumen stenosis, or both, associated with a given calcium burden was broad. Three hundred thirty-one coronary segments showed no calcification by computed tomography. Although atherosclerotic disease was found in several corresponding pathologic specimens, > 97% of these noncalcified segments were associated with nonobstructive disease (< 75% area stenosis); if no calcification was determined in an entire coronary vessel, all corresponding coronary disease was found to be nonobstructive. To determine the relation between arterial calcification and any atheromatous disease, computed tomographic calcium burden for each segment was paired with the histologic absence or presence of disease. Ultrafast computed tomographic scanning had a sensitivity and specificity of 59% and 90% and a negative and positive predictive value of 65% and 87%, respectively. A direct correlation was found (r = 0.99) between total calcium burden calculated from tomographic scans of the heart as a whole and scans of the arteries obtained in cross section. The detection of coronary calcification by ultrafast computed tomographic scanning is highly predictive of the presence of histopathologic coronary disease, but the use of this technique to define the extent of coronary disease may be limited. However, the absence of coronary calcification at any site is highly specific for the absence of obstructive disease.


Decreased concentration of myofibrils and myofiber hypertrophy are structural determinants of impaired left ventricular function in patients with chronic heart diseases: a multiple logistic regression analysis. The aim of this study was to perform a multiple logistic regression analysis to identify independent structural determinants of impaired left ventricular function. The association between contractile failure and structural alterations of the myocardium has been demonstrated in several studies, and multiple interactions between myocardial structure and cardiac performance are likely. Morphometric data assessed from 130 left ventricular biopsy specimens were analyzed. The endomyocardial specimens were obtained from 57 patients with normal coronary arteries (17 with normal left ventricular ejection fraction and 40 with impaired left ventricular function [dilated cardiomyopathy]), 15 patients with hypertrophic cardiomyopathy and 32 patients with aortic valve disease. Transmural biopsy specimens were assessed in 6 donor hearts before heart transplantation and in 20 patients with left anterior descending coronary artery disease whose specimens were obtained from the left ventricular anterior wall during aortocoronary bypass surgery. Global or regional left ventricular function was evaluated from left cineventriculograms. The volume fraction of cardiac fibrous tissue, intracellular volume fraction of myofibrils, volume fraction of myofibrils related to myocardial tissue (including fibrosis) and myofiber diameters were determined from semithin sections of the biopsy specimens with the use of light microscopic morphometry. Multiple logistic regression analysis revealed decreased volume fraction of myofibrils (p < 0.005) and increased fiber diameter (p < 0.002) as independent determinants of impaired left ventricular function. These data indicate that, independent of the underlying heart disease, both decreased concentration of contractile proteins and myocyte hypertrophy are independently associated with impaired left ventricular function.


Relation between Doppler color flow variables and invasively determined jet variables in patients with aortic regurgitation. The purpose of this study was to test the hypothesis that invasively derived jet variables including regurgitant orifice area and momentum determine the characteristics of Doppler color flow jets in patients with aortic regurgitation. In vitro studies have demonstrated that the velocity distribution of a regurgitant jet is best characterized by the momentum of the jet, which incorporates orifice area and velocity of flow through the orifice. Peak jet momentum, peak flow rate and regurgitant orifice area were determined with intraaortic Doppler catheter and cardiac catheterization techniques in 22 patients with chronic aortic regurgitation. These invasively derived variables were compared with apical and parasternal long-axis Doppler color echocardiographic variables obtained in the catheterization laboratory. Jet momentum increased significantly with the angiographic grade of regurgitation. The apical color jet area of aortic regurgitation increased linearly with jet momentum and regurgitant orifice area in vivo, but the correlations were only moderately good (r = 0.63 and 0.65, respectively). Color jet length also increased linearly with jet momentum and with regurgitant orifice area. There was only a trend for Doppler color jet width to increase with all invasively derived jet variables. Whereas jet area by Doppler color flow imaging is directly related to both orifice area and jet momentum in vivo, Doppler color variables measured in planes normal to the orifice do not correlate well enough with either jet momentum or regurgitant orifice area to predict jet flow variables in patients with aortic regurgitation. It is likely that the important influence of adjacent boundaries will limit the use of the velocity distribution of aortic regurgitant jets for determining the severity of disease.


Target lesion calcification in coronary artery disease: an intravascular ultrasound study. The purpose of this study was to evaluate the frequency, amount and distribution of target lesion calcification in patients undergoing transcatheter therapy for symptomatic coronary artery disease. Coronary artery target lesion calcification may be an important determinant of response to transcatheter therapy: balloon angioplasty causes dissections in calcified lesions, directional atherectomy cuts calcium poorly, rotational atherectomy causes preferential ablation of calcium and laser irradiation effect may vary. Intravascular ultrasound imaging is a highly sensitive technique for detection of plaque calcification in vivo. We performed intravascular ultrasound imaging before or after, or both, various transcatheter therapies in 110 patients. These 84 men and 26 women had a mean age of 60 years and a duration of angina of 22 +/- 34 months. Forty-nine patients had one-vessel, 29 had two-vessel, 25 had three-vessel and 7 had left main coronary disease. Vessels treated and imaged were the left main (n = 7), left anterior descending (n = 47), left circumflex (n = 18) and right (n = 38) coronary arteries. Eighty-four patients (76%) had target lesion calcification; 29 patients had one-quadrant, 25 had two-quadrant, 17 had three-quadrant and 13 had four-quadrant calcification. The calcification was superficial in 42 patients, deep in 13 and both superficial and deep in 31. The axial length of calcium could be measured in 29 patients; it was < or = 5 mm in 11 and > or = 6 mm in 18. Fluoroscopy detected calcification in 50 patients (48%, p < 0.001 vs. detection by ultrasound); this proportion increased to 74% in patients with calcification of two or more quadrants and to 86% in patients with calcification > or = 6 mm in length of two or more quadrants. Calcification was more common in patients who smoked and tended to be more common in patients with multivessel disease or previous coronary artery bypass graft surgery. We conclude that target lesion calcification occurs in 75% of patients with symptomatic coronary artery disease requiring angioplasty. Target lesion calcification is best detected, localized and quantified by intravascular ultrasound. These observations may be important in selecting devices for transcatheter therapy.


Surgical treatment of adult atrial septal defect: early and long-term results. The purpose of this study is to determine the early and late results of the surgical repair of atrial septal defect in adults. Progressively limiting, untreated atrial septal defect can lead to the early death of middle-aged adults. Recently it has been suggested that the closure of atrial septal defects might be accomplished with interventional cardiac techniques. Although the long-term results of the transcatheter closure are as yet unknown, the outcome of surgical therapy has been shown to be beneficial for almost 40 years. Between 1971 and 1991, 166 consecutive patients underwent surgical repair of a secundum or sinus venosus atrial septal defect, or both, at the Brigham and Women's Hospital, Boston. There were 120 women and 46 men in this group; the mean age was 44 years and 58 (35%) of the patients were > or = 50 years old. The average pulmonary to systemic flow ratio was 3.0, and 57 patients had a peak systolic pulmonary artery pressure > 30 mm Hg. There were two operative deaths (early mortality rate 1.2%), and 13% of the patients had a perioperative complication. One hundred fifty-three of the 164 survivors were followed up for a mean of 90 months (range 2 to 247). There were eight late deaths (late mortality rate 4.9%) and a late morbidity rate of 12.4% (in most cases due to arrhythmias). The 5- and 10-year survival rates are 98% and 94%, respectively, and the probability of event-free survival (with no morbidity or mortality) at 5 years is 97% and at 10 years is 92%. The results indicate that the surgical correction of atrial septal defect in adults is safe and efficacious as confirmed by 20 years of follow-up.


Physiologic changes with maximal exercise in asymptomatic valvular aortic stenosis assessed by Doppler echocardiography. We hypothesized that the physiologic response to exercise in valvular aortic stenosis could be measured by Doppler echocardiography. Data on exercise hemodynamics in patients with aortic stenosis are limited, yet Doppler echocardiography provides accurate, noninvasive measures of stenosis severity. In 28 asymptomatic subjects with aortic stenosis maximal treadmill exercise testing was performed with Doppler recordings of left ventricular outflow tract and aortic jet velocities immediately before and after exercise. Maximal and mean volume flow rate (Qmax and Qmean), stroke volume, cardiac output, maximal and mean aortic jet velocity (Vmax, Vmean), mean pressure gradient (delta P) and continuity equation aortic valve area were calculated at rest and after exercise. The actual change from rest to exercise in Qmax and Vmax was compared with the predicted relation between these variables for a given orifice area. Subjects were classified into two groups: Group I (rest-exercise Vmax/Qmax slope > 0, n = 19) and Group II (slope < or = 0, n = 9). Mean exercise duration was 6.7 +/- 4.3 min. With exercise, Vmax increased from 3.99 +/- 0.93 to 4.61 +/- 1.12 m/s (p < 0.0001) and mean delta P increased from 39 +/- 20 to 52 +/- 26 mm Hg (p < 0.0001). Qmax rose with exercise (422 +/- 117 to 523 +/- 209 ml/s, p < 0.0001), but the systolic ejection period decreased (0.33 +/- 0.04 to 0.24 +/- 0.04, p < 0.0001), so that stroke volume decreased slightly (98 +/- 29 to 89 +/- 32 ml, p = 0.01). The increase in cardiac output with exercise (6.5 +/- 1.7 to 10.2 +/- 4.4 liters/min, p < 0.0001) was mediated by increased heart rate (71 +/- 17 to 147 +/- 28 beats/min, p < 0.0001). There was no significant change in the mean aortic valve area with exercise (1.17 +/- 0.45 to 1.28 +/- 0.65, p = 0.06). Compared with Group I patients, patients with a rest-exercise slope < or = 0 (Group II) tended to be older (69 +/- 12 vs. 58 +/- 19 years, p = 0.07) and had a trend toward a shorter exercise duration (5.3 +/- 2.9 vs. 7.3 +/- 4.9 min, p = 0.20). There was no difference between groups for heart rate at rest, blood pressure, stroke volume, cardiac output, Vmax, mean delta P or aortic valve area. With exercise, Group II subjects had a lower cardiac output (7.4 +/- 2.4 vs. 11.5 +/- 4.6 liters/min, p = 0.005) and a smaller percent increase in Vmax (3 +/- 9% vs. 22 +/- 14%, p < 0.0001). Doppler echocardiography allows assessment of physiologic changes with exercise in adults with asymptomatic aortic stenosis. A majority of subjects show a rest-exercise response that closely parallels the predicted relation between Vmax and Qmax for a given orifice area. The potential utility of this approach for elucidating the relation between hemodynamic severity and clinical symptoms deserves further study.


Cardiac manifestations of cocaine abuse: a cross-sectional study of asymptomatic men with a history of long-term abuse of "crack" cocaine. The objective of this study was to evaluate the prevalence of cardiac abnormalities in young, asymptomatic long-term "crack" cocaine abusers. Although the cardiac complications of cocaine abuse have received widespread attention, the prevalence of cardiac abnormalities in asymptomatic long-term cocaine abusers is unknown. History, physical examination, electrocardiogram (ECG) and echocardiogram were performed in 52 consecutive long-term cocaine abusers admitted to a drug rehabilitation program. Findings were compared with those in 14 age-matched normal volunteers and 14 age-matched normotensive patients admitted to a psychiatric service who had a pattern of smoking and alcohol consumption similar to that of the study patients. The ECG findings were abnormal in 29% of cocaine abusers, and included nonspecific ST-T wave changes in 15%, abnormal ST segment elevation in 10%, old inferior infarction in 2%, old anteroseptal infarction in 2% and abnormal precordial R wave progression in 10%. When compared with normal volunteers and control patients, cocaine abusers had increased left ventricular posterior wall thickness (1.12 vs. 0.76 and 0.85 cm, respectively, p < 0.0001), increased septal thickness (1.13 vs. 0.76 and 0.86 cm, p < 0.001) and higher left ventricular mass index (142 vs. 84 and 94 g/m2, p < 0.0001). Left ventricular diastolic filling variables did not differ significantly among the three groups. Diastolic filling variables were similar in cocaine abusers with and without left ventricular hypertrophy, and the prevalence of left ventricular hypertrophy did not differ significantly between those who used no alcohol or < 35 ml/week of alcohol and those who consumed > or = 500 ml/week of alcohol. Left ventricular segmental wall motion abnormalities were present in 11 subjects (21%) and the ejection fraction was decreased (< 0.45) in 2 (4%). Electrocardiographic and echocardiographic abnormalities are common in long-term cocaine abusers. Despite the frequent occurrence of left ventricular hypertrophy, Doppler-derived diastolic filling pattern was not altered. Concomitant alcohol use did not affect the prevalence of these abnormalities.


Congenital cleft of the anterior tricuspid leaflet with severe tricuspid regurgitation in adults. Severe primary tricuspid regurgitation in the adult is a rare finding. This study describes the diagnostic findings and the treatment of an isolated congenital cleft of the anterior leaflet of the tricuspid valve as the morphologic substrate for severe tricuspid regurgitation. The clinical, echocardiographic findings and the follow-up findings of five patients (all male, 20 to 56 years old) with this disorder are described. Four of the five patients underwent cardiac surgery that confirmed the diagnosis. In three of five patients, exertional fatigue was the limiting symptom (New York Heart Association functional classes II and III). The clinical findings included a holosystolic murmur and supraventricular arrhythmias in all patients. Cardiac catheterization, performed in four patients, yielded the incorrect diagnosis of Ebstein's anomaly in three. In one patient the cleft was associated with an atrial septal defect of the secundum type. In four of five patients successful reconstruction of the tricuspid valve with a DeVega annuloplasty was performed. One patient had a partial excision of the right atrium, and one had a closure of a coexisting atrial septal defect. One patient refused operation. Tricuspid valve anomalies can be accurately identified by Doppler echocardiography. Surgical repair is the treatment of choice in patients with severe tricuspid regurgitation due to a congenital cleft of the anterior leaflet of the tricuspid valve.


Electrocardiographic detection of left ventricular hypertrophy by the simple QRS voltage-duration product. The object of this study was to assess the hypothesis that the product of QRS voltage and duration, as an approximation of the time-voltage integral of the QRS complex, can improve the electrocardiographic (ECG) identification of left ventricular hypertrophy. Electrocardiographic identification of left ventricular hypertrophy has been limited by the poor sensitivity of standard voltage criteria. However, increases in left ventricular mass can be more closely related to increases in the time-voltage integral of the summed left ventricular dipole than to changes in voltage or QRS duration alone. Antemortem ECGs were compared with left ventricular mass at autopsy in 220 patients. There were 95 patients with left ventricular hypertrophy, defined by left ventricular mass index > 118 g/m2 in men and > 104 g/m2 in women. The voltage-duration product was calculated as the product of QRS duration and Cornell voltage (Cornell product) and the 12-lead sum of QRS voltage (12-lead product). At partitions with a matched specificity of 95%, each voltage-duration product significantly improved sensitivity for the detection of left ventricular hypertrophy when compared with simple voltage criteria alone (Cornell product 51% [48 of 95] vs. Cornell voltage 36% [34 of 95], p < 0.005 and 12-lead product 45% [43 of 95] vs. 12-lead voltage 31% [30 of 95], p < 0.001). Sensitivity of both the Cornell product and 12-lead product was significantly greater than that found for QRS duration alone (28%, 27 of 95, p < 0.005) and the Romhilt-Estes point score (27%, 26 of 95, p < 0.005), and compared favorably with the sensitivity of the complex Cornell multivariate score (44%, 42 of 95, p = NS). Comparison of receiver operating characteristic curves demonstrated that improved performance of the voltage-duration products for the detection of left ventricular hypertrophy was independent of test partition selection. In addition, test performance of the voltage-duration products was not significantly affected by the presence or absence of a bundle branch block. These data suggest that the simple product of either Cornell or 12-lead voltage and QRS duration can identify left ventricular hypertrophy more accurately than can voltage or QRS duration criteria alone and may approach or exceed the performance of more complex multiple regression analyses.


Development and validation of a logistic regression-derived algorithm for estimating the incremental probability of coronary artery disease before and after exercise testing. Our goals were to develop and validate a multivariate algorithm for estimating the incremental probability of the presence of coronary artery disease. Multivariate methods, including logistic regression analysis, have been extensively applied to diagnostic exercise testing. However, few previous studies have included both an incremental design and external validation. A retrospective collection of clinical, exercise test and catheterization data was performed involving four U.S. referral medical centers. All patients had no prior history of coronary disease and had undergone coronary angiography < or = 3 months after exercise stress testing. An algorithm was developed in one center (590 patients with a 41% prevalence of coronary artery disease) with the use of logistic regression analysis and was validated in the other three centers (1,234 patients, 70% prevalence). The algorithm incorporated pretest variables (age, gender, symptoms, diabetes, cholesterol), exercise electrocardiographic (ECG) variables (mm of ST segment depression, ST slope, peak heart rate, metabolic equivalents [METs], exercise angina) and one thallium variable. Discrimination was measured with receiver operating characteristic curve analysis. Calibration (that is, reliability) was assessed from a comparison of probability estimates and the actual prevalence of disease. The overall incremental receiver operating characteristic curve areas for the validation group were pretest, -0.738 +/- 0.016; postexercise ECG, 0.78 (SE 0.017); and postthallium, 0.82 (SE 0.016); p < 0.01 for both increments. Within the three validation institutions, the institution with a disease prevalence closest to that of the derivation institution had the best incremental receiver operating characteristic curve areas. There was a stepwise incremental improvement in calibration especially from exercise ECG to thallium testing. An incremental multivariate algorithm derived in one center reliably estimated disease probability in patients from three other centers. The incremental value of testing was best demonstrated when the derivation and validation groups had a similar disease prevalence. This algorithm may be useful in decision making that relates to the diagnosis of coronary disease.


Adjunctive thrombolytic therapy for angioplasty in ischemic rest angina: results of a double-blind randomized pilot study. A multicenter pilot study was instituted to assess the role of intracoronary thrombolytic therapy during angioplasty for ischemic rest angina. Acute thrombotic coronary occlusion is increased during angioplasty for unstable angina, and intracoronary thrombolytic agents have been used to maintain patency. Prophylactic use of intracoronary thrombolytic agents has been advocated in certain high risk subgroups, although no studies have randomized therapy. Ninety-three patients with either unstable angina and pain at rest (trial A, 66 patients) or postinfarction pain at rest (trial B, 27 patients) were randomized in double-blind fashion to administration of either intracoronary urokinase, 150,000 U, or saline solution placebo given immediately before angioplasty. Cineangiograms of the culprit lesion were recorded and analyzed in blinded fashion by a core laboratory for definite or possible (haziness) filling defects 15 min after angioplasty or after acute closure. Urokinase decreased filling defects at 15 min after angioplasty in comparison with placebo (14% vs. 29%, respectively, p = 0.08). Four patients in each treatment group developed acute vessel closure. However, although urokinase significantly reduced the incidence of filling defects in trial A (3% vs. 23%, p = 0.03), the drug had no effect at the selected dose in trial B (42% vs. 43%, respectively). Acute vessel closure occurred significantly more frequently in trial B than in trial A, and urokinase at the selected dose also had no effect. Ischemic events after angioplasty appeared to be related more to dissection than to thrombosis, although redilation, which was more frequent after placebo administration, may have reduced their incidence as well as that of acute closure. These data suggest a possible role for intracoronary urokinase during angioplasty for unstable angina. The lack of effect after infarction may represent a greater thrombus burden or degree of plaque disruption. A trial utilizing higher doses of urokinase in a larger patient group is in progress.


Effects of steal-prone anatomy on intraoperative myocardial ischemia. The SPI Research Group. Our study objective was to determine whether the presence of steal-prone anatomy conferred an increased risk in the development of intraoperative myocardial ischemia. Coronary artery steal of collateral blood flow has been demonstrated for many vasodilators, including isoflurane, the most commonly used inhalational anesthetic agent in the United States. It has been postulated that patients with steal-prone anatomy (total occlusion of one coronary artery that is supplied distally by collateral flow from another coronary artery with a > or = 50% stenosis) may be particularly at risk for the development of intraoperative myocardial ischemia when an anesthetic with a vasodilator property is being administered. We evaluated the risk of myocardial ischemia under isoflurane anesthesia (vs. a high dose narcotic technique using sufentanil) using continuous intraoperative electrocardiography and transesophageal echocardiography in patients with and without steal-prone anatomy undergoing coronary artery bypass graft surgery. Sixty-two (33%) of the 186 patients had steal-prone anatomy: in 5 (8%) the collateral-supplying vessel was > or = 50% to 69% stenosed, in 24 (39%) it was > or = 70% to 89% stenosed and in 33 (53%) it was > or = 90% stenosed. The incidence of ischemia (transesophageal echocardiography or intraoperative electrocardiography, or both) was similar in patients with and without steal-prone coronary anatomy (18 [29%] of 62 patients vs. 39 [31%] of 124 patients, p = 0.87, 95% confidence interval = -0.13 to 0.17). The incidence of intraoperative ischemia was similar in patients who received isoflurane or sufentanil anesthesia (20 [32%] of 62 patients vs. 37 [30%] of 124 patients, p = 0.87). The incidence of tachycardia and hypotension was low (increases in heart rate = 9.8%, and decreases in systolic blood pressure = 10.8% of total monitoring time during the prebypass period compared with preoperative baseline values). The incidence of adverse cardiac outcome was similar in patients with and without preoperative steal-prone coronary anatomy (4 [7%] of 62 patients vs. 14 [11%] of 124 patients, p = 0.53). These findings demonstrate that under strict hemodynamic control the presence of steal-prone anatomy does not confer an increased risk in the development of intraoperative myocardial ischemia.


Effects of sotalol on the signal-averaged electrocardiogram in patients with sustained ventricular tachycardia: relation to suppression of inducibility and changes in tachycardia cycle length. This study examines the effects of sotalol on the signal-averaged electrocardiogram (ECG) in patients with spontaneous and inducible sustained ventricular tachycardia and correlates these findings with the effect of sotalol on tachycardia inducibility and tachycardia rate. Standard electrocardiography generally does not detect any change in the duration of the QRS complex resulting from sotalol therapy. However, the signal-averaged ECG is more sensitive than the standard ECG for detecting changes in QRS duration induced by antiarrhythmic drugs and can also detect changes in late potential duration. Signal-averaged electrocardiography was performed before therapy in 30 patients with spontaneous and inducible ventricular tachycardia, and both electrophysiologic study and a signal-averaged ECG were repeated during therapy with d,l-sotalol. During sotalol therapy the signal-averaged QRS duration decreased by 2.6 +/- 6.6 ms in the 11 patients with no inducible tachycardia during therapy, whereas it increased by 3.8 +/- 5.8 ms (p = 0.01) in the 19 patients with inducible tachycardia during therapy. In the latter group there was a significant positive correlation between prolongation of tachycardia cycle length and prolongation of late potential duration by sotalol (r = 0.56, p = 0.01). Sotalol can alter QRS and late potential duration as measured by the signal-averaged ECG. Prolongation of QRS duration or late potential duration may reflect a slowing of conduction by sotalol that may interfere with this agent's antiarrhythmic efficacy and slow ventricular tachycardia.


Electrocardiographic and electrophysiologic characteristics of anterior, midseptal and right anterior free wall accessory pathways. The objective of this study was to define the electrocardiographic (ECG) and electrophysiologic characteristics of midseptal, anteroseptal and right anterior free wall accessory pathways. The fully pre-excited 12-lead surface ECGs and ECGs during orthodromic atrioventricular (AV) reentrant tachycardia were compared for 13 patients with an anteroseptal, 7 with a midseptal and 7 with a right free wall accessory pathway. Routine electrophysiologic studies were performed in all and stimulation of the right ventricular summit during tachycardia was accomplished in 10 patients. Differences in the surface ECGs were not sufficiently sensitive to distinguish among accessory pathway locations. Premature ventricular complexes induced from the right ventricular septal summit during ventricular activation either advanced the succeeding atrial depolarization or terminated the tachycardia in three of six patients with a septal pathway and in none of the four with a right anterior pathway. The change in ventriculoatrial (VA) interval with the development of right bundle branch block during orthodromic AV tachycardia proved most helpful in distinguishing these pathways. Patients with a right anterior free wall pathway showed a change in VA interval > or = 40 ms, whereas those with an anteroseptal pathway showed changes of 20 to 30 ms and those with a midseptal pathway showed no change. Anteroseptal, midseptal and right anterior free wall pathways may be distinguished by using programmed stimulation of the summit of the right ventricular septum and especially with changes in the VA interval with development of right bundle branch block during orthodromic AV reentrant tachycardia.


Frequency analysis of signal-averaged electrocardiogram in patients with right ventricular tachycardia. The purpose of this study was to analyze the frequency content of signal-averaged electrocardiograms (ECGs) in patients with idiopathic ventricular tachycardia of right ventricular origin and in patients with arrhythmogenic right ventricular dysplasia. The late potentials in the time domains are usually found in patients with arrhythmogenic right ventricular dysplasia. They are not usually found in patients with idiopathic ventricular tachycardia of right ventricular origin. Fast Fourier transform analysis of signal-averaged ECGs was performed with the use of a Blackman-Harris window in 43 subjects: 20 normal volunteers (group I), 12 patients with idiopathic ventricular tachycardia of right ventricular origin (group II) and 11 patients with arrhythmogenic right ventricular dysplasia (group III), and the frequency spectrum was displayed in a three-dimensional graph. Area ratio (ratio of the area under the spectral plot from 40 to 120 Hz to the area from 0 to 120 Hz) was calculated in all subjects. Area ratio was significantly higher in group II than in group I (243 +/- 45 vs. 196 +/- 15, p < 0.01) and significantly higher in group III (396 +/- 51) than in group I or II (p < 0.001). The high frequency components in group II were confined within the QRS complex in the three-dimensional graph, whereas those in group III extended outside the QRS complex. Frequency analysis of the signal-averaged ECG with fast Fourier transform analysis can detect the high frequency components in patients with right ventricular tachycardia, including idiopathic ventricular tachycardia and arrhythmogenic right ventricular dysplasia.


Improved reproducibility of left atrial and left ventricular measurements by guided three-dimensional echocardiography. The objective of this study was to determine whether guided three-dimensional echocardiography could improve the reproducibility of left atrial and left ventricular anteroposterior measurements over that of standard unguided two-dimensional echocardiography. Although these measurements are standard indexes for evaluating chamber size, their use is limited by significant interobserver variability largely due to variable image plane positioning. To improve measurement accuracy and reproducibility, we have developed a three-dimensional echocardiograph that displays the line of intersection of the real-time image with a previously saved orthogonal reference image. This display shows the relation of the real-time image to anatomic landmarks in its third, nonvisualized dimension and may be used to guide image positioning. Three pairs of operators independently performed unguided two-dimensional and guided three-dimensional examinations on three groups of 10 patients each. The left atrium was measured in a plane through the inferior surface of the aortic cusps and the left ventricle in a plane perpendicular to its long axis 1 cm below the mitral leaflet tips. Interobserver variability of these measurements on unguided parasternal long-axis images and on guided short-axis images was assessed. The standard unguided two-dimensional examination was associated with an interobserver variability of 14.6% and 9.1% for atrial and ventricular measurements, respectively. Guided three-dimensional echocardiography significantly reduced interobserver variability to 5.0% and 3.1%, respectively, for the same measurements (p < 0.005 by McNemar's test). Significant interobserver variability occurs with standard unguided two-dimensional echocardiographic measurement of left atrial and left ventricular dimensions. Guided three-dimensional echocardiography achieves a nearly threefold improvement of reproducibility of these measurements and provides the basis for improved serial evaluation and comparison of atrial and ventricular size by different operators.


Quantification of left to right atrial shunts with velocity-encoded cine nuclear magnetic resonance imaging. The purpose of this study was to evaluate the ability of velocity-encoded nuclear magnetic resonance (NMR) imaging to quantify left to right intracardiac shunts in patients with an atrial septal defect. Quantification of intracardiac shunts is clinically important in planning therapy. Velocity-encoded NMR imaging was used to quantify stroke flow in the aorta and in the main pulmonary artery in a group of patients who were known to have an increased pulmonary to systemic flow ratio (Qp/Qs). The velocity-encoded NMR flow data were used to calculate Qp/Qs, and these values were compared with measurements of Qp/Qs obtained with oximetric data derived from cardiac catheterization and from stroke volume measurements of the two ventricles by using volumetric data from biphasic spin echo and cine NMR images obtained at end-diastole and end-systole. Two independent observers measured Qp/Qs by using velocity-encoded NMR imaging in 11 patients and found Qp/Qs ranging from 1.4:1 to 3.9:1. These measurements correlated well with both oximetric data (r = 0.91, SEE = 0.35) and ventricular volumetric data (r = 0.94, SEE = 0.30). Interobserver reproducibility for Qp/Qs by velocity-encoded NMR imaging was good (r = 0.97, SEE = 0.20). Velocity-encoded NMR imaging is an accurate and reproducible method for measuring Qp/Qs in left to right shunts. Because it is completely noninvasive, it can be used to monitor shunt volume over time.


Left ventricular mass and body size in normotensive children and adults: assessment of allometric relations and impact of overweight. This study was designed to determine the most appropriate method to normalize left ventricular mass for body size. Left ventricular mass has been normalized for body weight, surface area or height in experimental and clinical studies, but it is uncertain which of these approaches is most appropriate. Three normotensive population samples--in New York City (127 adults), Naples, Italy (114 adults) and Cincinnati, Ohio (444 infants to young adults)--were studied by echocardiography. Relations of left ventricular mass to body size were similar in all normal weight groups, as assessed by linear and nonlinear regression analysis, and results were pooled (n = 611). Left ventricular mass was related to body weight to the first power (r = 0.88), to body surface area to the 1.5 power (r = 0.88) and to height to the 2.7 power (r = 0.84), consistent with expected allometric (growth) relations between variables with linear (height), second-power (body surface area) and volumetric (left ventricular mass and body weight) dimensions. Strong residual relations of left ventricular mass/body surface area to body surface area (r = 0.54) and of ventricular mass/height to height (r = 0.72) were markedly reduced by normalization of ventricular mass for height2.7 and body surface area1.5. The variability among subjects of ventricular mass was also reduced (p < 0.01 to p < 0.002) by normalization for body weight, body surface area, body surface area1.5 or height2.7 but not for height. In 20% of adults who were overweight, ventricular mass was 14% higher (p < 0.001) than ideal mass predicted from observed height and ideal weight; this increase was identified as 14% by left ventricular mass/height2.7 and 9% by ventricular mass/height, whereas indexation for body surface area, body surface area1.5 and body weight erroneously identified left ventricular mass as reduced in overweight adults. Normalizations of left ventricular mass for height or body surface area introduce artifactual relations of indexed ventricular mass to body size and errors in estimating the impact of overweight. These problems are avoided and variability among normal subjects is reduced by using left ventricular mass/height2.7. Simple nomograms of the normal relation between height and left ventricular mass allow detection of ventricular hypertrophy in children and adults.


Tachycardia, contractility and volume loading alter conventional indexes of coronary flow reserve, but not the instantaneous hyperemic flow versus pressure slope index. Because measurements of flow reserve are often made in the setting of fluctuating hemodynamic variables that cause alterations in basal or hyperemic coronary blood flow, traditional flow reserve indexes may be difficult to interpret. Prior work in this laboratory has suggested that the instantaneous hyperemic flow versus pressure slope index is a more hemodynamically stable alternative to measures of flow reserve. Although this index has no hemodynamic dependence on changes in aortic pressure, the extent to which it is affected by other factors that alter myocardial work is unknown. Therefore, the purpose of this investigation was to analyze the effects of tachycardia (induced by atrial pacing at 10 beats/min above the basal heart rate), dobutamine infusion (10 micrograms/kg per min) and saline solution volume loading (500 ml) on measurements of traditional coronary flow reserve, the resistance reserve ratio and the instantaneous hyperemic flow versus pressure slope index. Twenty-nine open chest anesthetized dogs were studied in four sequential stages: baseline, tachycardia, dobutamine infusion and saline solution volume loading. Traditional coronary flow reserve was defined as the ratio of hyperemic coronary blood flow to basal coronary blood flow, the resistance reserve ratio as the ratio of basal coronary resistance to hyperemic coronary resistance and the instantaneous hyperemic flow versus pressure slope index as the slope of the instantaneous relation between diastolic hyperemic coronary blood flow and diastolic aortic pressure normalized by perfusion bed weight. Hyperemia was induced by intravenous adenosine infusion (1 mg/kg per min). Mean aortic pressure was kept nearly constant during the interventions by manipulation of an aortic clamp or a vena caval snare. The final study group comprised 18 open chest dogs. Coronary flow reserve was significantly decreased by tachycardia (3.7 +/- 1.2 to 3.0 +/- 1.2, p < 0.0001), decreased by saline solution volume loading (3.2 +/- 1.3 vs. 2.7 +/- 0.8, p = 0.06) and significantly increased by dobutamine infusion (3.2 +/- 1.3 to 4.3 +/- 1.5, p < 0.0005). In contrast, the instantaneous hyperemic flow versus pressure slope index was not affected by the three interventions (7.4 +/- 3.1 vs. 7.3 +/- 3.3, 7.4 +/- 3.2 vs. 7.4 +/- 3.4 and 7.5 +/- 3.1 vs. 7.3 +/- 3.4, respectively, all p = NS). The changes observed in the resistance reserve ratio were of similar or greater magnitude and significance to the changes in coronary flow reserve. The instantaneous hyperemic flow versus pressure slope index offers a hemodynamically stable alternative to measures of vascular reserve because it is independent of moderate changes in heart rate, contractility and volume loading that may occur commonly in clinical situations.


Prediction of immediate ventricular arrhythmias after coronary artery ligation. Our aim was to test the hypothesis that increased beat to beat morphologic variations in the body surface electrocardiogram (ECG) are associated with fragmented diastolic electrical activity that appears after coronary artery ligation and to correlate the appearance of spontaneous ventricular fibrillation after coronary ligation with the magnitude of the ECG beat to beat variability. Unstable and variably delayed electrical activation precedes the development of ventricular fibrillation in dogs with acute ischemia. Detection of these highly variable low amplitude signals from the body surface is currently impossible. We have developed a system designed to measure the degree of beat to beat variability of the ECG. With high fidelity electrocardiography, subtle beat to beat ECG morphologic variations were detected in epicardial and body surface electrograms and quantified as the variance of the ECG voltage at specific points of the cardiac cycle. The ratio of the variance at the QRS offset to that of the QRS onset (beat to beat variability index) was then calculated. Ventricular fibrillation developed in 12 of 27 dogs after left anterior descending coronary artery ligation. In 7 of the 12 dogs it occurred immediately (< 15 min) after ligation; in the other 5 it developed late (> 15 min) after ligation. Dogs with subsequently immediate ventricular fibrillation had a significantly higher beat to beat variability index than that of dogs with late or no ventricular fibrillation both before coronary ligation (4.7 +/- 1.4 vs. 1.1 +/- 0.2 and 0.8 +/- 0.1, respectively, p < 0.001) and after ligation (6.4 +/- 2.6, 1.0 +/- 0.6 and 1.2 +/- 0.6, respectively, p < 0.001). In dogs that developed ventricular fibrillation immediately after coronary ligation, the arrhythmia was preceded by fragmented diastolic electrical activity on the epicardial electrogram and a simultaneous increase in the beat to beat morphologic variability of the terminal portion of the body surface ECG QRS complex. Beat to beat QRS offset morphologic variations appear to be increased before and further increased after coronary artery ligation in dogs that develop ventricular fibrillation immediately after ligation. Increased beat to beat variability index may be associated with the presence of electrophysiologic instability and can predict early ventricular fibrillation.


Comparison of technetium-99m sestamibi and thallium-201 retention characteristics in canine myocardium. The aim of this study was to compare the myocardial retention of technetium-99m (Tc-99m) sestamibi and thallium-201 over a wide range of blood flow at different time points after tracer injection. Technetium-99m sestamibi has been proposed as a new perfusion tracer with better physical characteristics than those of thallium-201 for scintigraphic imaging. However, no studies have simultaneously compared the ability of both tracers to assess myocardial blood flow during pharmacologic vasodilation. The myocardial retention of Tc-99m sestamibi and thallium-201 were compared over a wide range of blood flow induced by regional coronary occlusion and dipyridamole infusion in an open chest dog model. Myocardial retention of both tracers was determined by in vitro tissue counting at 2, 5, and 20 min after tracer injection and was correlated with microsphere-determined blood flow. Thallium-201 demonstrated greater absolute tissue retention than did Tc-99m sestamibi. At 2 min after tracer injection, there was an almost linear relation between the retention of both tracers and myocardial blood flow over a wide flow range. However, this relation was not maintained over time. At 20 min after injection, the retention of both tracers underestimated myocardial blood flow at higher flow rates. At 2, 5 and 20 min after injection, increments of relative tracer retention between the different levels of flow were always greater for thallium-201 than for Tc-99m sestamibi. Thallium-201 displays more suitable physiologic characteristics as a flow tracer and may allow better differentiation of myocardial regions with different levels of coronary flow reserve. For both tracers, early cardiac imaging may minimize underestimation of blood flow at higher flow rates.


The restenosis paradigm revisited: an alternative proposal for cellular mechanisms. Coronary restenosis is a reparative response to arterial injury during angioplasty, and remains a major clinical problem. The reasons for treatment failures likely stem from our incomplete understanding of the cellular mechanisms in restenotic neointimal formation. Restenosis is thought to result from migration and replication of medial smooth muscle cells to form an obstructive neointima, a concept neither observed nor demonstrated in humans. An alternative hypothesis for restenosis is based on observations in the porcine coronary injury model. In this model, there are three cellular stages in neointimal formation: thrombotic (stage I), cellular recruitment (stage II) and proliferative (stage III). The thrombotic stage occurs early and consists of platelets, fibrin and red blood cells accumulating at the vessel injury site. In the recruitment stage, the mural thrombus itself develops an endothelium, followed by a mononuclear leukocytic infiltrate beginning on the lumen side of the vessel. In the proliferative stage, a "cap" of actin-positive cells forms on the lumen surface and progressively thickens. These cells do not arise from media at the injury site. Extracellular matrix secretion and additional recruitment likely add to neointimal volume during this phase. Thrombus assumes a major role in restonosis by providing an absorbable matrix into which smooth muscle cells proliferate. Further studies are needed to validate or modify this hypothesis.


Respiratory effects of air pollution on allergic disease. Allergic patients have an increased susceptibility to the adverse effects of both natural and man-made air pollutants. This goes for both indoor and outdoor air pollutants and manifests itself with biochemical, cellular, and pathophysiologic expressions of adverse health effects in allergic individuals. Also occupationally induced allergic diseases will remain very important. This area has been reviewed recently by Cullen et al. Since allergic patients comprise somewhere between 15% and 20% of the population, this increased susceptibility is of crucial importance not only for medical care and research but for legislative and regulatory consideration to protect these vulnerable individuals.


The association of individual allergen reactivity with respiratory disease in a national sample: data from the second National Health and Nutrition Examination Survey, 1976-80 (NHANES II). The independent association of individual allergen reactivity with respiratory disease was evaluated with use of the second National Health and Nutrition Examination Survey, a sample of the U.S. white civilian population, ages 6 to 24 years (n = 4295). Eight, 1:20 wt/vol, 50% glycerol, unstandardized extracts were administered by prick puncture. Allergen reactivity was reported as the percent with a mean erythema diameter 10.5 mm or greater at 20 minutes. Only the prevalence of asthma and allergic rhinitis increased with the increasing number of positive allergen skin tests. The independent association of individual allergen reactivity with respiratory disease was quantified with logistic models that included other allergen reactivity, age, sex, smoking, and region. Asthma was associated with reactivity to house dust (odds ratio, 2.9; 95% confidence interval [CI] 1.7 to 5) and Alternaria (odds ratio, 5.1; 95% CI: 2.9 to 8.9). Allergic rhinitis was associated with reactivity to ragweed (odds ratio, 2.3; 95% CI: 1.5 to 3.3); ryegrass (odds ratio, 2.8; 95% CI: 1.8 to 4.3); house dust (odds ratio, 2.5; 95% CI: 1.6 to 3.9); Alternaria (odds ratio, 2.3; 95% CI: 1.5 to 3.4). Asthma only (without allergic rhinitis) was associated with dust and Alternaria. Allergic rhinitis only (without asthma) was associated with ryegrass, ragweed, and house dust. When both asthma and allergic rhinitis were present, only house dust and Alternaria remained associated. These findings highlight the association of specific allergens with upper and lower respiratory diseases and the interactions among coexisting respiratory diseases.


Specific serum immunopatterns in clinical phases of allergic bronchopulmonary aspergillosis. Immunoblotting, radioallergosorbent test (RAST), and enzyme-linked immunosorbent assay (ELISA) were performed to determine specific IgE and IgG responses to Aspergillus fumigatus (Af) allergens (IgE-Af; IgG-Af). Serology results were compared in patients with allergic bronchopulmonary aspergillosis (ABPA) (n = 43), patients with Aspergillus fumigatus-associated asthma (Af-asthma) (n = 26), and healthy individuals (n = 3). In patients with different clinical phases of ABPA, three specific immunopatterns were found by immunoblotting. It is proposed to classify ABPA into the active, intermediate, and remission phase with respect to the specific immunoresponse to Af-allergens and asthma symptoms. First, the active phase of ABPA is characterized by a fully developed specific immunoresponse to Af-allergens and severe asthma. Second, the intermediate phase includes patients with elevated specific immunologic findings without asthma symptoms. Third, the remission phase is characterized by a weak specific immunoresponse to Af-allergens after a long-term asymptomatic period. No correlation occurred between specific immunopatterns and irreversible brochopulmonary lesions. The IgE-Af RAST and IgG-Af ELISA titers of patients with ABPA in the active and intermediate phase were significantly higher compared with patients with ABPA in remission phase and with patients with Af-asthma. In particular, the demonstration of positive IgG-Af ELISA titer generally allows the serologic discrimination of patients with asthma and ABPA from patients with Af-asthma in clinical practice. The present study revealed that immunoblots of most patients with Af-asthma were negative. Immunoblotting demonstrated an IgG reactivity exclusively to low molecular weight (MW) Af-allergens in 8 out of 26 patients with Af-asthma and in the three healthy individuals, and this IgG response may reflect naturally occurring antibodies.


The role of water temperature and laundry procedures in reducing house dust mite populations and allergen content of bedding. The effects of various laundry procedures on house dust mites and their allergens have been established. All mites were killed by water temperatures 55 degrees C or greater. Killing at lower temperatures was not enhanced by any of the pure detergents or laundry products tested. A cold cycle of laundry washing with or without laundry powder did not remove most live mites from bedding, however, the allergen concentration (Der p I/gm fine dust) was reduced by more than 90%. Dry cleaning did not reduce the allergen concentration of the dust, although most, if not all, mites were killed.