The late cardiotoxic effects of anthracycline chemotherapy influence morbidity and mortality in the growing population of childhood cancer survivors. Even with lower anthracycline doses, evidence of adverse cardiac remodeling and reduced exercise capacity exist. We aim to examine the relationship between cardiac structure, function and cardiovascular magnetic resonance (CMR) tissue characteristics with chemotherapy dose and exercise capacity in childhood cancer survivors.2). CMR measured ventricular function, mass, T1 and T2 values, and myocardial extracellular volume fraction, ECV, a measure of diffuse fibrosis based on changes in myocardial T1 values pre- and post-gadolinium. Cardiac function was also assessed with conventional and speckle tracking echocardiography.Thirty patients (15 ± 3 years), at least 2 years following anthracycline treatment, underwent CMR, echocardiography, and cardiopulmonary exercise testing . Increased ECV correlated with decreased mass/volume ratio (r = −0.64), decreased LV wall thickness/height ratio (r = −0.72), lower peak VO2(r = −0.52), and higher cumulative dose (r = 0.40). Echocardiographic measures of systolic and diastolic function were reduced compared to normal values (p < 0.01), but had no relation to ECV, peak VO2 or cumulative dose.Patients had normal LVEF (59 ± 7%) but peak VO1 and ECV were found to be early tissue markers of ventricular remodeling that may represent diffuse fibrosis in children with normal ejection fraction post anthracycline therapy, and are related to cumulative dose, exercise capacity and myocardial wall thinning.Myocardial T The conmatocrit . The consurement . All resTwo-dimensional echocardiography was performed using a Vivid 7 ultrasound platform . Traditional systolic and diastolic functional parameters measured included: fractional shortening (FS), peak early filling (E velocity), late filling (A velocity), medial and lateral LV tissue Doppler (TDI) peak systolic velocity (S’), peak early diastolic velocity (E’), peak late diastolic velocity (A’), and E/E’ ratios. The basal short axis and apical 4-chamber views were used to obtain speckle tracking echocardiography global circumferential and longitudinal strain, and global circumferential and longitudinal strain rate (SR) in systole and early diastole, during a breath-hold at end-expiration. Echocardiographic measures were analysed offline using EchoPAC software . The echocardiographic parameters were compared to 30 healthy normal controls of similar ages from our existing institutional database, who had previously undergone full functional echocardiography studies at rest using M-mode, 2D, TDI and STE measuring the same parameters.2, was determined as the highest oxygen consumed over a 30-second period.Incremental exercise testing with expired gas analysis was performed on a cycle ergometer with an initial power output of 10–15 watts, increasing by 5–10 watts every 2 minutes according to the subject’s fitness capacity. Heart rate was continuously monitored with 12-lead ECG, and blood pressure measured every two-minutes with a cuff sphygmomanometer. Expired gases were collected with a commercially available metabolic measurement system . Maximum oxygen consumption, peak VOA Pearson correlation (|r|) greater than 0.48 would be detectable with 83% power assuming a 0.05 significance level (α) and null hypothesis correlation of 0, with 30 patients. Thirty patients also achieved an effect size of 0.46 to compare CMR parameters to known reported normal values with 80% power if α = 0.05. Assuming a standard deviation of 10, a 4.6 unit minimum decrease compared to normal MRI values would be detected. Power calculations were completed using PASS 2008.2 was compared with healthy reported age and gender matched normals [1 and ECV to continuous MRI values, anthracycline dose and peak VO2. Gender was included as an independent variable for all comparisons. A significance level of 0.05 was used. Statistical analysis was performed using SPSS  and S-Plus 8.0 for Windows, Insightful Corp. 2008 .Data are presented as mean ± standard deviation. Peak VO normals . DiffereOut of 50 eligible patients, 30 agreed to participate with the following cancer diagnoses: 10 acute lymphocytic leukemia, 11 lymphomas , 2 acute myelocytic leukemia, 2 Wilms’ tumour, 1 Ewing’s sarcoma, 2 neuroblastoma, 1 osteosarcoma, and 1 hemangiopericytoma. The major reasons for declining to participate were the need for intravenous access for MRI contrast administration and unwillingness to have an MRI scan. The characteristics of patients who participated did not differ from those who declined with regard to age, gender, anthracycline dose, and previous chest irradiation as shown in Table 2). For conventional echocardiography parameters (Table 2 or anthracycline dose.Patients and controls used for comparison of echocardiography parameters were similar in age (15.2 ± 2.7 years versus 13.8 ± 3.4 years), gender  and BSA  and C), and with corresponding T1 pixel maps in B) and D). Figures 1 values (1155.3 ± 56.5 ms) were similar to previous reports using the same method [1 (1191.7 ± 50.0 ms vs 1122.8 ± 37.9 ms) and ECV (23.0 ± 3.7% vs 18.7 ± 3.1%) compared to males.A sample Te method ,13. The e method . Females2 , left ventricular mass/volume ratio  and wall thickness/height ratio  , reduced mass/volume , and reduced wall thickness/height ratios , but did not correlate with peak VO2  were within normal reported ranges [1 or ECV, mass/volume or wall thickness/height ratios. There were no significant relationships between any of the echocardiographic parameters and ECV, T1, or T2 values.Myocardial ECV showed significant correlations with anthracycline dose , peak VOd ranges ,14 and w2 was 35 ± 10 ml/kg/min  and peak HR was 188 ± 17 bpm [2  family of pulse sequences has reported non-contrast myocardial T1 values ranging from 939 to 1029 ms at 1.5 T [1 values with MOLLI as compared to SASHA are expected and reflect the dependence of the MOLLI method on T2 values and inversion pulse efficiency among other factors, including the specific implementation of MOLLI [1 values but similar small ranges of values, 1175 ± 27 ms and 936 ± 25 ms, respectively [1 values with acquisition method also result in differences in the calculated ECV, and thus care must be taken to interpret these values in the context of the specific acquisition method.Quantitative myocardial Tmyopathy ,20, myocmyopathy -23 and ssubjects ,25, and at 1.5 T -29. The of MOLLI ,30,31. Aectively . These sA recent study by Neilan et al. has examined the ECV in adults with previous anthracycline exposure, showing an increased ECV in patients compared to controls . However2, and had a wide range of peak VO2, ranging from 28 to 60 ml/kg/min, illustrating the broad range of potential chemotherapy toxicity in the study population. The measurement of the correlations of ECV and baseline T1 values with the cumulative dose, as well as with morphological changes associated with myocardial atrophy, such as reduced wall thickness normalized to height and reduced mass/volume, was enabled in the current study by the wide range of values for all measures.Similar to the Neilan study, all patients in our study were negative for late gadolinium enhancement, which is also in agreement with most of the literature to date. Reports of late gadolinium enhancement in late anthracycline cardiotoxicity are few, with subendocardial enhancement being a novel finding and only reported in 2 patients, 10 and 14 years after anthracycline treatment . In cont2 values in our study were also similar to normal values from previous studies [2 values, and a lack of correlation between T2 and T1 values in our subjects, it is unlikely that increased baseline T1 values observed in the current study are related to edema.CMR measures of global function and mass were largely within the normal range in our patients. Average myocardial T studies ,38, indiThe echocardiographic findings of decreased longitudinal and circumferential strain, and longitudinal SR in patients is comparable with the work of others demonstrating reduced LV myocardial deformation parameters as evidence of subclinical anthracycline cardiotoxicity ,9,39. Co2 is the gold standard measure of aerobic fitness [2 in patients was able to differentiate between controls and patients post-anthracycline therapy, but that cardiac dysfunction, as measured with echocardiography at rest or with exercise, was not significantly related to reduced exercise capacity. [2 and its inverse correlation with ECV in our patients suggests a cardiotoxic contribution to the reduced whole body fitness. However, the potential direct toxic effects on skeletal muscle and vascular system, occurring in conjunction with cardiac damage, cannot be excluded and thus the cardiac contribution to reduced peak VO2 cannot be determined. Other factors such as respiratory or musculoskeletal function or deconditioning from a sedentary lifestyle following previous chronic illness may also reduce the specificity of peak VO2 to cardiac damage [Peak VO fitness . De Caroapacity. . The sigc damage .1 and ECV.A limitation of the current study is the lack of an age-matched control group for the CMR acquisitions. Nonetheless, the strength of our findings are the significant correlation of ECV with cumulative dose, exercise capacity and structural measures of remodeling, as opposed to their absolute values as compared to controls. Another limitation is the heterogeneous population of diagnoses, radiation, and varying treatment protocols with differing length of follow-up, which were likely important sources of variability for all findings. The study is also limited by the lack of a comparison to a gold stand and measure of fibrosis in subjects with exposure to anthracyclines. Future human or animal studies would ideally compare biopsy evaluation of myocardial microstructure with non-contrast T1 values and calculated ECV correlate with cumulative chemotherapy dose, exercise capacity and subtle structural remodeling, which may have the potential to characterize myocardial tissue changes prior to functional alterations. These novel measures of diffuse fibrosis may prove to be early non-invasive tissue biomarkers of chronic anthracycline cardiotoxicity in the future.In children, following anthracycline therapy, myocardial TECV: Extracellular volume fraction; EDV: End-diastolic volume; EF: Ejection fraction; ESV: End-systolic volume; FS: Fractional shortening; IVRT: Isovolumic relaxation time; SR: Strain rate.The authors declare that they have no competing interests.ET contributed to the conception and design of the study, patient recruitment and consent, and supervised the CMR, echocardiography and exercise testing. MH contributed to the conception and design of the study and performed the exercise testing. KC designed the CMR sequences, performed the CMR and helped to draft the manuscript. MS contributed to the conception and design of the study, and identified suitable patients. SK was involved in patient recruitment, performing the echocardiograms, and analyzed the functional echocardiographic parameters. NK was involved in performing the echocardiograms, and critically revised the manuscript for important intellectual content. JP performed or supervised the CMR and helped to draft the manuscript. AM contributed to the conception and design of the study, provided statistical support, and critically revised the manuscript for important intellectual content. RT designed the CMR sequences, performed or supervised the CMR and drafted the manuscript. All authors read and approved the final manuscript.


Manual planimetry for quantitative analysis of ejection fraction (EF) and infarct size (IS) on cardiac magnetic resonance (CMR) imaging are too time-consuming, and therefore, impractical in daily clinical practice. We sought to derive and examine the predictive accuracy of a semi-quantitative scoring technique to screen patients with an EF ≤35% or an IS ≥18.5%, known independent predictors of increased cardiac events and mortality.The CMR derivation cohort consisted of 122 ST-segment elevation myocardial infarction patients. The validation cohort consisted of an additional 172 patients from the multi-center DEfibrillators To REduce Risk by MagnetIc ResoNance Imaging Evaluation (DETERMINE) trial. Cines were scored on a 17-segment model for wall motion and totaled for the Sum Motion Score (SMS): 0 = normal, 1 = mild hypokinesis, 2 = moderate to severe hypokinesis, 3 = akinesis, 4 = dyskinesis. Viability images were scored for infarct transmurality and totaled for the Sum Infarct Score (SIS): 0 = none, 1 = 1-25%, 2 = 26-50%, 3 = 51-75%, 4 = 76-100%. Quantitative EF and IS were manually planimetered using QMass (Medis).From the derivation cohort, the SMS correlated with EF  and SIS correlated with IS . Linear regression equations between SMS vs. EF and SIS vs. IS were obtained to estimate EF (est-EF = 55 - SMS) and IS (est-IS = 1.383 * SIS).In the validation cohort, the mean EF was 39.0 ± 11.7% (32% with EF ≤35%), and the mean IS was 17.3 ± 10.4% (40% with IS ≤18.5%). Using the derivation formula, the est-EF (36.2 ± 10.9%) correlated with EF (R = 0.9) with a slight underestimation of the mean difference by 2.8 ± 4.9%. In addition, the est-IS (21.8 ± 12.8%) correlated with IS (R = 0.9). The est-IS tended to overestimate IS by 4.5 ± 5.9%. The sensitivity for detecting an EF ≤35% using the est-EF was 94% with a negative predictive value of 97%. The sensitivity for detecting an IS ≥18.5% using the est-IS was 96% with a negative predictive value of 96%.Semi-quantitative scoring is a sensitive screening tool that can be used to identify patients with an ejection fraction ≤35% or infarct size ≥18.5% to provide a rapid alternative method to manual planimetry.


In this study, we have used equilibium contrast CMR (EQ-CMR) to assess the interstium volume of patients after atrial redirection surgery, finding higher amounts than in healthy volunteers and correlations with known clinical markers of disease.After atrial redirection surgery (the Mustard and Senning operations) for transposition of the great arteries (TGA) the systemic right ventricle (RV) suffers from late systolic failure with resultant high morbidity and mortality. The mechanisms of late systemic RV failure are poorly characterised. We hypothesised that diffuse interstitial expansion representing diffuse fibrosis would be greater in the right ventricles of patients following Mustard or Senning surgery and that it would be associated with other markers of heart failure and disease severity in these patients.We used Equilibrium Contrast CMR to quantify interstitial expansion,Vd(m), in the septum and RV free wall of 14 consecutive adults presenting to a tertiary specialist clinic late after palliative surgery for TGA ). These were compared to an equal number of age and sex matched healthy volunteers from a denominator normal population of 86. Patients were also assessed with a standardised CMR protocol, NT-proBNP and cardiopulmonary exercise (CPEX) testing.Mean septal Vd(m) was significantly higher in the patients than in the control population . NT-proBNP was positively related to septal Vd(m)  was difficult to measure  with high and poor inter-observer reproducibility such that this analysis was abandoned.In this small preliminary study, septal interstitial expansion is seen in adults late after atrial redirection surgery for TGA. It correlates well with NT-proBNP and chronotropic incompetence and may have a role in the development of RV systolic impairment. Measuring interstitial expansion in the RV free wall is difficult using this methodology.British Heart Foundation.


CMR T2-mapping is a promising tool for characterizing myocardial edema. We applied T2-mapping in volunteers to compare two mapping sequences and to assess feasibility, reproducibility and spatial homogeneity.We scanned 26 volunteers  with a normal ECG, no cardiac disease and no symptoms of inflammation.Using a 1.5 T scanner and a dedicated 12-element cardiac coil we applied a FLASH-based and SSFP-based mapping sequence in midventricular short axis (SAX) and four-chamber-view (4CV). The map was based on three images with an echo time of 0, 24 and 55 ms. Spatial resolution was 2.1 mm/pixel. Scan time was 12 heart beats.In Osirix 3.3.2. we manually drew 6 segments in SAX and 4CV, each. Additionally, we drew a global region of interest (ROI) covering the whole LV myocardium in SAX and 4CV. The same investigator analyzed 10 data sets twice. 5 volunteers were scanned twice on separate days. Results were compared with a paired student t-test.After excluding one subject due to obvious pathologies, 25 datasets with sufficient image quality were evaluated. Table FLASH and SSFP correlated better in 4CV than in SAX . T2-values did not correlate with heart rate (p=0.3).With both sequences anteroseptal segments had higher T2-values than inferior and inferolateral segments in SAX . In 4CV the basal septum had higher T2-values than the anterolateral segment with FLASH , but not with SSFP . Mean absolute difference between a single segment and a global measurement was 4±1 ms and 3±1 ms for FLASH and SSFP in SAX and 5±2 ms for FLASH and SSFP in 4CV (p=0.3).Mean difference for repeated analysis was 1.6±1.9 ms (correlation coefficient 0.9) and 2.2±2.2 ms (correlation coefficient 0.7) for repeated scans.T2-mapping is feasible with low intraobserver variability and does not depend on heart rate. SSFP-based T2-mapping resulted in slightly higher values than FLASH. Mapping in 4CV resulted in higher T2-values than in SAX. We could detect small spatial differences across the heart. However, these intraindividual spatial variations were smaller than considerable interindividual variability.


Exercise tolerance is often impaired in children with hypoplastic left heart syndrome(HLHS). It has been hypothesised this may be related to diastolic dysfunction of the single systemic right ventricle (RV), ventricular hypertrophy or to restricted pre-load from limited pulmonary venous return in Fontan physiology.1.Children with HLHS referred for dobutamine stress MRI catheterisation were assessed with MRI volumetry and invasive pressure measurements at rest and at 10mcg/kg/min and 20mcg/kg/min of dobutamine. Results were normalised for body surface area and compared with normal adult left ventricle (LV) and RVFour patients were studied (indication was decreased exercise tolerance). Median (range) age was 9.2 years5.9-11.6). Heart rate (HR) increased at both levels of stress: mean (standard deviation) at rest 60(±7.0), 10mcg/kg/min 110.8±13.7), 20mcg/kg/min 137.5(±7.0). The rate of increase between rest and 10mcg/kg/min appeared higher than in the normal group. Indexed end diastolic volume (iEDV) fell considerably more between rest and 10mcg/kg/min compared to both the normal LV and RV(figure 1.6. Hear.7, 20mcgDobutamine stress MRI in HLHS patients after Fontan completion appears to be safe and feasible, may provide insights into the physiology of the systemic RV at stress, and can potentially contribute to the understanding of decreased exercise tolerance in this group.


Patients with left neglect were tested with “chimeric” figures composed of the right and left halves of two different objects. The connectivity relation was modulated between the two half figures. For some displays, the two chimeric halves were separated by a small gap, while in others, the separate halves were connected by a line segment. In line with previous reports, performance on reporting the left half improved when the chimera were separated; but when a line connected the two separated halves the advantage was lost. If the connecting line was broken, the performance was again enhanced. The results suggest an important role for connectedness in the representation of perceptual objects and in the distribution of attention in neglect. Patients with right hemisphere lesions The distinction, between within- and between-object spatial codes, can be used to account for the pattern of neglect reported by Young, Hellawell and Welch The present study sought to investigate the influence of a perceptual object based on connectedness on neglect. Do the beneficial effects of connectedness with low-level (meaningless) stimuli  also hold with higher-level (meaningful) objects? Humphreys and Riddoch Here we report two experiments. In Experiment 1 we manipulated connectedness by either having a line or a gap between two separate half-figures, and performance in these conditions was compared with performance with the original chimeric figures. In Experiment 2 we sought to generalize our findings by using a random curve to represent general connectedness and a broken line to represent the gap condition rather than merely spatial isolation. We examined whether connecting the two halves alleviated or aggravated spatial neglect.Ten patients  with left unilateral neglect participated (10 in Experiment 1 and 9 in Experiment 2) and provided written consent. Patients were all right handed and had normal or corrected-to-normal vision. Detailed information of each patient is described in The stimuli were presented at the center of a 14.1-inch HP laptop computer set at 60 Hz, which was laid on the right side of the patients' body midline at a viewing distance of approximately 60 cm. The figures were dark against the light screen. Eye movements were neither limited, nor monitored.The chimeric figures in this study were generated from 30 drawings of animals and common objects from Snodgrass and Vanderwart The procedure of the experiment was almost the same as that employed by Buxbaum and Coslett p = 0.007) and Chimeric-Connected condition (mean = 48%) . There was no difference in performance between the Chimeric and Chimeric-Connected conditions .The right half-figures under the three experimental conditions  were well recognized by all patients with mean accuracy of 99.7%. The Wilcoxon signed-rank test was used to analyze the data. There were two aims to Experiment 2. First, we wished to generalize the connectedness effect by using a random curve instead of a straight line segment. Second, we controlled for the presence of the line in the connected condition by including a broken line in the gap condition. This was to exclude the possibility that the line itself rather than connectedness per se influenced the performance of the neglect patients.p = 0.007) and Chimeric-Connected figures (53%) . There was no significant difference between the Chimeric and Chimeric-Connected conditions .The right sides of the chimeric stimuli were correctly reported by all the patients. All naming errors were made to the left sides of the chimerics. As shown in We have demonstrated here a negative influence of connectedness on the ability to name the left-side item of a chimeric pair. We have shown that when a central gap was introduced between the two halves of chimeric figures, the patients' ability to recognize the left sides of these figures was improved in line with prior findings Beneficial effects of connectedness have been reported previously, but typically relate to studies employing simple geometric stimuli Our results are relevant to the issue of whether neglect operates in space- or object-based coordinates. Egocentric neglect is associated with more anterior lesions than allocentric neglect; however, many neglect patients show both forms  et al.Connected chimeric halves appear to be processed as an integrated whole object rather than two individual objects given the performance under Chimeric-Connected condition (mean = 50.5%) was more similar to that under Chimeric (mean = 50.25%) rather than Chimeric-Gap conditions (mean = 70.6%). According to Grabowecky Connectedness has been adopted by researchers to dissociate the object vision and space vision. Tipper and Behrmann In conclusion, the present study provides a clear demonstration of a modulation effect of connectedness in neglect, and suggests that neglect could be based on the formation of perceptual units at the early stages of visual processing when connectedness plays a key role.


The prevalence of cardiac abnormalities in Noonan’s syndrome is high. Pulmonary valve and artery stenoses commonly require intervention in this group with short and long term sequelae. Cardiovascular magnetic resonance (CMR) is the imaging modality of choice for assessment of right ventricular size and function.We aimed to determine the prevalence and severity of right ventricular and pulmonary abnormalities by CMR in patients with Noonan’s syndrome that had undergone prior pulmonary valve or artery intervention for stenosis.CMR scans of patients with Noonan’s syndrome referred for imaging were analyzed. All patients were imaged on a 1.5T MRI. RV volumes were generated from SSFP cines and normalized to gender, body surface area and age. Phase contrast velocity mapping was used to assess pulmonary and aortic flow. The prevalence of concomitant cardiovascular abnormalities was also assessed.2 = 8.4; p = 0.037) and severe (regurgitant fraction 26.4±5% (mean ± SEM) vs. 6.5 ± 3%; p<0.01) in the prior intervention group. Although indexed RV end-diastolic volumes were also greater , no difference was observed in RVESV, RVEF or wall thickness, nor right atrial area . Mild to moderate PV stenosis was seen in 5 (33%) with prior intervention and 4 (24%) without. Other abnormalities included tricuspid dysplasia , anomalous pulmonary venous drainage , aortic coarctation , aortic root dilatation , myxomatous mitral valve , evidence of previous ASD repair , VSD repair  and AVSD repair .Thirty two consecutive patients (age 29 (20 - 50), (median (IQR); male 69%) were studied. Prior intervention for MPA or PV stenosis was performed in 15 (47%) patients and data was compared to 17 (53%) Noonan’s patients without MPA or PV intervention. Pulmonary regurgitation was more prevalent (73% vs. 33%, χCMR-determined moderate and severe pulmonary regurgitation is frequent in patients with Noonan’s syndrome after pulmonary intervention. RV function remains well preserved despite increased volume load. CMR, an ideal imaging modality for the assessment of pulmonary valve and RV function also allows detection of associated cardiac abnormalities in Noonan’s syndrome.


For regional parameters correlation coefficients ranged from 0.83 to 0.85 for baseline and from 0.70 to 0.79 for peak DSE. Both methods provided good and similar feasibility with only 1 % segments excluded from analysis at peak stage of DSE with shorter time and lower coefficient of variance offered by AFI. Global and regional longitudinal strain achieved by faster and less operator-dependent AFI method correlate well with standard more time-consuming STE analysis during baseline and peak stage of DSE.Speckle tracking echocardiography (STE) is a method of quantitative assessment of myocardial function complementary to ejection fraction and visual evaluation. Standard STE analysis, demands manual tracing of the myocardium whereas automated function imaging (AFI) offers more convenient (based on selection of three points) assessment of longitudinal strain. Nevertheless, feasibility and correlation between both methods were not thoroughly examined, especially during tachycardia at peak stage of dobutamine stress echocardiography (DSE). We performed DSE in 238 patients (pts) with recording of apical views during baseline (0) and peak (1) DSE and analyzed them by STE and AFI. According to angiography, 127/238 pts had significant (≥70 %) lesions in coronary arteries. We assessed correlations between STE and AFI derived peak systolic longitudinal strain values for global and regional parameters, feasibility, time of analysis and interobserver agreement. Global systolic longitudinal strain measured during baseline and peak stage of DSE by AFI showed very good correlation with standard STE parameters, with correlation coefficients r = 0.90 and r = 0.86 respectively ( Stress echocardiography is, besides nuclear imaging, one of the leading noninvasive tests widely applied in the diagnosis of coronary artery disease , 2. The We examined 238 subjects  with symptoms suggesting stable angina and scheduled for myocardial ischemia testing. The study protocol encompassed: medical history, physical examination, resting ECG and laboratory data , transthoracic echocardiographic examination, dobutamine stress echocardiography with early atropine administration (DSE) and angiographic examination in all patients performed no later than 3 months after DSE. The assessment of coronary arteries was done by invasive coronary angiography in 208 patients and by computed tomography in 35 subjects (5 patients had both examinations). As significant lesion stenosis ≥50 % for left main coronary artery (LMCA) and ≥70 % for others epicardial arteries was defined. All study patients were in sinus rhythm and had no significant valve disease (except for mild to moderate insufficiency). Exclusion criteria included contraindications to dobutamine and atropine: acute coronary syndromes, valve or outflow tract stenosis, blood pressure >200/100 mmHg, ventricular tachycardia, glaucoma or prostatic adenoma. Demographic characteristics and echocardiographic data of the examined subjects are displayed in Tables Transthoracic echocardiography was performed with VIVID 7 Dimension  using M4S probe in harmonic mode 2.0/4.3 MHz with maximal frame per second (FPS) count available at necessary sector width. Range of FPS was from 64 to 112 with mean value 83. The assessment of left ventricular (LV) systolic and diastolic volumes and ejection fraction was done using a modified Simpson’s method from triplane view obtained with volumetric probe 3 V. Mass of LV was calculated from Devereaux’s formula with measurements of LV walls and cavity was performed according to Penn convention. Wall thickness and chamber dimensions were measured from 2D imaging in parasternal long axis view. The echocardiographic measurements were done following American Society of Echocardiography/European Association of Echocardiography guidelines. The assessment of left ventricular contractility was done visually by two experts and classified for each segment as norm kinesis, hypokinesis, akinesis or diakinesis. 18-segments model of left ventricle was applied dividing each of LV wall visualized from apical projections into three segments: basal, mid and apical. The worsening of contractility in at least two adjacent segments of left ventricle was consistent with a positive dobutamine stress test. Early atropine administration protocol was applied. Dobutamine was administered in the intravenous infusion in doses of 10, 20, 30 and 40 μg/kg/min during 3-min stages whereas atropine was added in 0.5 mg fractional doses after the second stage of infusion up to the total dose of 2 mg. The infusion of dobutamine was stopped when age-adjusted HR limit, positive stress test result or other criteria for terminating DSE were fulfilled. For safety reasons, the presence of minimum two persons during each study was mandatory, BP was measured during each stage of test, 12-lead ECG was recorded immediately after stopping dobutamine infusion and a prolonged observation up to 1 h after the test was scheduled.0 and SLS1 respectively, systolic longitudinal strain). Additionally, the averaged values of SLS for each apical view were measured and global SLS from 18 left ventricle segments was calculated. The obtaining of regional and global systolic longitudinal strain by AFI method demanded manual marking of three points  in each apical view and accepting the resulting region of interest. The rounded segmental values of peak systolic longitudinal strain were displayed in a straightforward format of polar map with additional information regarding the averaged (obtained from six segments) and global (obtained from 18 segments) systolic longitudinal strain.Digital loops from standard echocardiographic views  were digitally stored at baseline and peak stage of the infusion for further analysis. The calculation of regional and global parameters of deformation was done off-line using EchoPac 6.1.0 workstation (GE Vingmed Ultrasound). The allocation of regional values of longitudinal strain by standard 2D speckle tracking imaging required manual marking of endocardial contour and adjustment of the region of interest to encompass the myocardial wall in all three apical views. For the analysis, we assigned left ventricular segments with consecutive numbers in clockwise order starting from basal septum in 4-chamber view, through 2-chamber to 3-chamber view. Mid-segments from lateral wall, inferior wall and anterior septum were chosen as marker segments for the circumflex, right coronary artery and left anterior descending artery territories respectively. The annotation of the myocardial segments and definition of region supplied by respective coronary arteries are displayed in Fig. The parameters measured by both techniques were defined as the peak deformation in longitudinal direction achieved for assessed segment during systole, before the aortic valve closure. Correlations were calculated for global and regional longitudinal strain in all segments.t Student test for paired variables. Chi square test was used to test the dichotomous variables distribution. For comparison of parameters obtained by STE and AFI Pearson correlation coefficients were calculated and Bland–Altman analysis performed. For interobserver variability assessment we calculated coefficients of variance. Duration of STE and AFI calculations and interobserver agreement were assessed in the group of 12 randomly selected subjects.Statistical analysis was performed using MedCalc V. 12.1.4. (Frank Schoonjans Belgium). Continuous variables were expressed as means and standard deviations. Mean values were compared with p < 0.0001. Interobserver variability (coefficient of variance) calculated for regional longitudinal strain in segment number one  was 8.7 and 16 % respectively for AFI at baseline and peak stage of DSE and for STE 13.3 and 24.2 %.Time needed to analyze and obtain regional, averaged (from six segments) and global (from 18 segments) systolic longitudinal strain by classic STE was 367 ± 39 s and by AFI 168 ± 28 s, the difference was statistically significant with p = 0.0001 for STE and p = 0.0007 for AFI) whereas the differences of feasibility between STE and AFI respectively at baseline and stress were not significant.To our study we included only subjects (n = 238) in which visual assessment of endocardium was feasible in all left ventricular segments , we excluded—six patients (2.5 %) from the study because of insufficient visualization. Suboptimal quality of 2D image—as assessed automatically by software despite manual correction of region of interest- led to exclusion of 11 segments (0.26 %) from STE and 18 segments (0.42 %) from AFI analysis at rest. During the peak stage of DSE 41 segments (0.96 %) were suboptimal for STE analysis and 46 (1.07 %) were suboptimal for AFI quantification and excluded from the analysis. For both methods proportion of segments with suboptimal quality was significantly higher at peak stage of stress test than at baseline  is displayed in Table p < 0.0001), see Fig. Expectedly, dobutamine induced the increase of heart rate, blood pressure, ejection fraction and peak velocities of mitral annulus as summarized in Table p < 0.0001), although correlation coefficients for measurements performed at baseline were slightly higher than during peak stage of dobutamine test. In the Fig. The comparison of regional deformation parameters measured in subsequent left ventricular segments indicated highly significant linear relationship of values from both methods  but with limited interobserver agreement, especially when systolic longitudinal strain was measured during significant tachycardia  at peak stage of test. The high observed feasibility of STE and AFI is comparable to values reported in the literature although the findings in our study may be influenced by preselection of the subjects with all segments suitable for visual assessment , 22.The novel, simplified AFI technique offered similar feasibility, lower coefficient of variance both during rest and peak stress stage (8.7 vs 13.3 % and 16 vs 24.2 % respectively) and significantly (about two times) shorter time needed for analysis. The preponderance of AFI over velocity vector imaging (VVI) -based strain calculations was observed in earlier studies concerning patients with suspected or documented coronary artery disease and using magnetic resonance strain imaging as a golden standard .As expected the localization of segments excluded from analysis was similar for both traditional STE and AFI with lower feasibility in regions of anterior, lateral and posterior wall  performed optimally as expert consensus by experienced and accordingly trained observers and supported by second harmonic imaging, echocardiographic contrast enhancement as needed, digital storage and quad screen format , 25, 26.Considering the known limitation of visual assessment of wall motion during echocardiographic stress test, especially those connected with significant tachycardia  and meticulous analysis necessary in standard STE, the novel AFI method appears faster, offering user-friendly polar maps of the left ventricle and thus a potential to become a useful clinical tool.The main limitation of our study is a lack of a golden standard for echocardiographic measures of deformation. Magnetic resonance imaging myocardial tagging could be proposed as a reference but its practical use is very limited. Instead, we focused on a direct comparison of two easily amenable echocardiographic modalities.Another limitation of our study is the exclusion of subjects with the suboptimal echocardiographic visualization assessment of endocardial border. Nevertheless the percentage of subjects excluded since suboptimal quality of visualization was really low (below 3 %) and the number of included examination still exceeded 200 DSE tests with sum >4,000 analyzed segments.Single-center character and the assessment of STE and AFI correlation confined to a single vendor of echocardiographic equipment may be considered as subsequent limitation of our study as evidence is growing regarding a poor agreement between different STE softwares.The quantitative assessment of longitudinal regional and global strain during DSE is feasible by both standard 2D STE and AFI methods. Parameters achieved by those techniques showed strong correlations at rest ant at the peak stage of dobutamine stress test. The shorter time necessary for analysis by AFI method and lower operator-dependency confirmed by improved interobserver agreement indicate potential utility of AFI for objective evaluation of left ventricular function during echocardiographic stress test.


Congenitally corrected transposition of the great arteries is a complex congenital cardiac anomaly with a wide spectrum of morphologic features and clinical profiles. Most patients are diagnosed late in their life, undergoes surgical repairs, eventually leading to systemic ventricular failure needing heart transplant or mechanical circulatory assistance. As, aorta is located anterior to and left of the PA (Transposition of great arteries), the outflow graft of ventricular assist device traverse across pulmonary artery to reach aorta which poses challenge during further surgical explorations. Congenitally corrected transposition of the great arteries (CCTGA) is a complex congenital cardiac anomaly with a wide spectrum of morphologic features and clinical profiles. Most patients are diagnosed late in their life, undergoes surgical repairs, eventually leading to systemic ventricular failure needing heart transplant or mechanical circulatory assistance. Normally, the outflow graft of the ventricular assist device (VADs), especially with new axial flow devices, ejects from the device and navigates by the right side of the heart to terminate into the ascending aorta. Due to the anatomical anomaly we describe a modificated surgical technique for positioning the ventricular assist device outflow graft.A 53 year old gentleman was diagnosed of congenitally corrected transposition of great arteries (CCTGA) with pulmonary stenosis in his thirties. He had DDD pacemaker implanted at that time for atrio-ventricular block. He was normally fit and active but had over the previous six months noticed a reduction in his effort capacity. His heart failure therapy was intensified with beta-blocker, ACE inhibitor and diuretics, despite he gradually deteriorated to NYHA class III. Echocardiography revealed moderately dilated, hypertrophied systemic ventricle with significant systolic impairment (Ejection Fraction of 14%). There was moderate tricuspid regurgitation. There was incoordination of both ventricles. It was decided to implant left ventricular assist device (LVAD) for significant systemic ventricular dysfunction secondary to CCTGA.th day and his long term goal remained heart transplantation.Chest was opened by sternotomy and patient was put on cardiopulmonary bypass through an arterial cannula in ascending aorta and two-stage venous cannula in right atrium. Heartmate II teflon ring was attached to the systemic ventricle using 16 pledgeted Polyester (Ethibond Excel) 2–0 sutures. The myocardium within the ring lumen was resected using coring knife and Heartmate II inflow cannula was then inserted through it. The outflow graft was anastomosed to ascending aorta using side biting clamp with a 4–0 running Polypropylene suture and de-aired by releasing clamps before knotting. The LVAD was started as CPB weaned off slowly to generate flows of 4 to 5 l/min. The post-operative course was smooth and the patient was ambulant on 4A computed tomography (CT) of the thorax was done in routine follow up after 6 months which showed the outflow graft of LVAD passing over Pulmonary artery (PA) under the upper sternum, transversing to the left and anastomosing to the side of aorta Figure . ReconstAdults with congenital heart defects and congestive heart failure are a challenging population because of its complex anatomy, prior surgical palliation, and hemodynamic status. Advances in palliation of congenital heart disease have resulted in improved survival to adulthood. Many of these patients ultimately develop end-stage heart failure requiring heart transplant or LVAD implantation.The CCTGA is characterized by atrio-ventricular and ventriculo-arterial discordance in which morphologic right ventricle functions as the systemic ventricle (SV), whereas the morphologic left ventricle functions as the pulmonary ventricle (PV). In this anomaly, the systemic atrio-ventricular valve (SAVV) is a morphologic tricuspid valve, whereas the pulmonary atrio-ventricular valve (PAVV) is a mitral valve ,2. The gAt the time of referral for surgical repair, the majority of these patients have significant SV dysfunction with advanced symptoms. Although excellent early surgical results can be achieved, residual impairment of the SV is common and may eventually necessitate cardiac transplantation ,6. SysteDevelopment in the field of mechanical circulatory assist devices in recent decades offer an additional option for patients of end stage heart disease with various aetiologies including congenital heart disease . If rapiNormally, the outflow graft of the VADs, especially with new axial flow devices, ejects from the device and navigates by the right side of the heart to terminate into the ascending aorta. Both in TGA and CCTGA, the aorta is located anterior to and left of the PA with various degrees of malrotation. Hence, the outflow graft has to traverse across the PA from right to left to reach the ascending aorta. This brings the graft under the sternum in close proximity. Reoperation is needed these cases for VAD explant, VAD up-gradation, pulmonary VAD implantation or eventual heart transplant. Re-entry through the median sternotomy is unavoidable under such circumstances. The outflow graft lying under the sternum yields a great risk of cutting through the graft which may leads to catastrophic haemorrhage and exsanguinations.Different techniques of reinforcing and positioning the outflow graft to make them less vulnerable at re-do sternotomy like tunnelling the graft in PTFE patch or through the right pleural cavity were reported . HoweverVentricular assist device implantation in patients with congenitally corrected transposition of great arteries is a technical challenge; however it can be performed in experienced transplantation units with an acceptable postoperative result.A written informed consent was obtained from the patient’s next of kin for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.The authors declare that they have no competing interests.PM wrote the manuscript, AP co-wrote the manuscript and managed figures; BZ and DG were involved in the concept, RH made critical revision of the manuscript, AK and AS approved the manuscript. All authors read and approved the final manuscript.


Obesity is associated with diastolic dysfunction, lower maximal myocardial blood flow, impaired myocardial metabolism and increased risk of heart failure. We examined the association between obesity, left ventricular filling pressure and myocardial structure.We performed histological analysis of non-ischemic myocardium from 57 patients (46 men and 11 women) undergoing coronary artery bypass graft surgery who did not have previous cardiac surgery, myocardial infarction, heart failure, atrial fibrillation or loop diuretic therapy.2, n=33) and obese patients  did not differ with respect to myocardial total, interstitial or perivascular fibrosis, arteriolar dimensions, or cardiomyocyte width. Obese patients had lower capillary length density  and higher diffusion radius , in comparison with non-obese patients. However, the diffusion radius/cardiomyocyte width ratio of obese patients (0.73±0.11 μm/μm) was not significantly different from that of non-obese patients (0.71±0.11 μm/μm), suggesting that differences in cardiomyocyte width explained in part the differences in capillary length density and diffusion radius between non-obese and obese patients. Increased BMI was associated with increased pulmonary capillary wedge pressure , and lower capillary length density was associated with both increased BMI (P=0.043) and increased PCWP (P=0.016).Non-obese (body mass index, BMI, ≤30 kg/mObesity and its accompanying increase in left ventricular filling pressure were associated with lower coronary microvascular density, which may contribute to the lower maximal myocardial blood flow, impaired myocardial metabolism, diastolic dysfunction and higher risk of heart failure in obese individuals. The increasing prevalence of obesity is a major health concern. Increased body mass index (BMI) has a well-established association with diastolic dysfunction and risk of heart failure, and diastolic dysfunction is a precursor to heart failure -3. The mAnimal models show obesity to be associated with cardiac hypertrophy and alterations in myocardial structure and coronary microvasculature -16. HumaTo investigate the hypothesis that obesity and its accompanying diastolic dysfunction are associated with alteration in myocardial structure we performed histological analysis of non-ischemic LV myocardial biopsies from patients without heart failure or previous myocardial infarction who were undergoing coronary artery bypass graft surgery. We previously reported that neither age, diabetes nor the metabolic syndrome was associated with altered myocardial total or interstitial fibrosis, cardiomyocyte width, capillary length density, diffusion radius or arteriolar dimensions in men from this patient population, although men with diabetes and the metabolic syndrome had lower perivascular fibrosis ,22. In tThe St. Vincent's Health Human Research Ethics Committee approved this research and all patients gave written informed consent.Details of the Cardiac Tissue Bank have been previously described . From thEach patient had a Swan-Ganz catheter inserted before surgery that provided a measure of pulmonary artery pressure, pulmonary capillary wedge pressure (PCWP) and cardiac output that were recorded immediately after induction of anesthesia. PCWP was measured at end-expiration by temporarily disconnecting the patient from the ventilator at the time of measurement, as previously shown to provide an accurate measure of left ventricular end-diastolic pressure .2 were considered to exceed the abdominal circumference threshold for the metabolic syndrome. A patient had diabetes if a history of diabetes was evident from use of glucose-lowering medications and/or insulin or if the fasting plasma glucose was ≥7 mmol/L [Fifteen patients had type 2 diabetes mellitus, another 27 had the metabolic syndrome and 15 had neither condition. The metabolic syndrome was defined according to the International Diabetes Federation . For patBlood hemoglobin and hemoglobin A1c and plasma creatinine were measured as part of the routine pre-surgery workup. All other variables were measured on fasting blood collected before induction of anesthesia on the day of surgery. Estimated glomerular filtration rate (eGFR) was calculated from the Modification of Diet in Renal Disease formula . InsulinDetails of tissue collection, fixation and histology have been previously described . All hisArterioles were identified by the presence of a layer of media and immunohistochemical staining for elastin showed the blood vessels were relaxed. The tissue was immersion fixed and the arterioles were usually oval in shape because of deformation and/or because they were cut at an oblique angle. We did not attempt to analyze arterioles in longitudinal section, and only arterioles in approximate cross-section or oblique-section were analyzed for perivascular fibrosis. Perivascular fibrosis ratio was calculated as the ratio of the area of perivascular fibrosis to the total vessel area . Arteriolar wall area/circumference ratio was calculated for arterioles with average diameters of 20-80 μm, which represented 86% of all arterioles counted.Cardiomyocyte width, determined on 4 μm sections of paraffin-embedded tissue (one section per patient) stained for reticulin, was the mean of >100 measurements for each section of the shortest diameter of cardiomyocyte profiles containing a nucleus. Capillary length density, which is the length of capillaries per unit volume of tissue, and diffusion radius, were determined by analysis of 4 μm sections of paraffin-embedded tissue (one section per patient) immunostained for CD31  using standard stereological techniques as previously described .t-test for continuous variables and χ2 or Fisher's exact tests for discrete variables. Regression analysis was performed using the method of least squares and correlations were estimated using Pearson correlation coefficients. All tests were two-tailed. Calculations were performed using Statview statistical software (SAS Institute Inc) and a two-sided P value of <0.05 was considered to indicate statistical significance.Data are presented as mean±SD for normally distributed variables and as median with 25th and 75th percentiles for variables that were not normally distributed. The normality of continuous data was verified with the Kolmogorov-Smirnov test and variables with a positively skewed distribution were log transformed before analysis. Categorical variables are expressed as number (%). Differences between groups were tested with The clinical, biochemical and hemodynamic characteristics of the study patients are shown in All biopsies were taken from a region of the LV wall without evidence of ischemia or wall motion abnormality and none of the biopsies showed evidence of ischemia . There wP=0.035); however, the lower capillary length density of the 7 obese women did not achieve statistical significance in comparison with the 4 non-obese women (P=0.10).When men and women were analyzed separately, capillary length density of the 17 obese men was less than that of the 29 non-obese men (P=0.036), but not the metabolic syndrome, had lower capillary length density. However, in regression analysis for the whole patient population, capillary length density was not associated with fasting plasma glucose, log fasting plasma insulin or log plasma triglyceride levels, or ß cell function (log HOMA2-%B), insulin sensitivity (log HOMA2-%S) or insulin resistance (log HOMA2-IR).Although obese patients were more likely to have hypertension, capillary length density was not associated with a history of hypertension or blood pressure at pre-admission or during surgery. In this population of 56 men and women, in comparison with patients without diabetes or the metabolic syndrome, analysis of variance showed that patients with diabetes (We confirmed the well-established association between BMI and diastolic dysfunction -3, and wAmong all organs, the heart is unique in that oxygen extraction is constantly close to maximal and the importance of the capillary bed to the ischemic vulnerability of the myocardium is well recognised -34. ReduA reduction in the number or density of microvessels has been reported in both clinical and experimental hypertension and diabetes , raisingPrevious studies of the mechanism of the association between increased BMI, diastolic dysfunction and the risk of heart failure have had difficulty separating the effects of BMI from the effects of the metabolic syndrome, impaired insulin sensitivity and cardiac hypertrophy ,39,40, aOur study highlights both similarities and differences between the effects of obesity on the myocardium of humans and animals. Animal models show obesity to be associated with cardiac hypertrophy -14, and Our study had a number of limitations. The sample size was limited by the need for myocardial biopsies from each patient and our study was therefore restricted to univariable analyses. Another limitation was the inherent selection bias caused by the sampling of patients presenting for coronary artery bypass graft surgery, and it is not known whether our findings apply to patients with less extensive coronary artery disease. However, patients with coronary artery disease were an important group to study because of the high prevalence of coronary artery disease in the community, and our previous studies showed that the presence of coronary artery disease per se does not influence myocardial fibrosis, cardiomyocyte width, capillary length density or arteriolar dimensions . To avoiIn summary, we showed that increased BMI and percent body fat and their accompanying increase in LV filling pressure were associated with lower coronary microvascular density, but not with alteration in myocardial fibrosis or arteriolar dimensions. Lower coronary microvascular density may contribute to the lower maximal myocardial blood flow, impaired myocardial metabolism, diastolic dysfunction and increased risk of heart failure risk in obese individuals.


Ventricular function is a primary indicator for the diagnosis and treatment monitoring of many cardiovascular diseases. Cardiac cine magnetic resonance imaging (MRI) with steady state free precession (SSFP) sequences is regarded to be the standard of reference for the assessment of ventricular function. However, manual segmentation of MRI data is a time consuming process and also suffers from inter/intra-observer variability. This justifies the development of more automated segmentation methods to reduce the amount of time and effort that an experienced operator must spend on this process, and to make such methods practical.The objective of this study was to validate our automated segmentation method developed to perform left and right ventricular function quantification from cardiac magnetic resonance images with a simple mouse click.Thirty patients with cardiovascular diseases were examined using a 1.5-T MRI unit . A stack of short axis slices with a thickness of 6-mm was planned according to the vertical and horizontal long-axis views, to cover both ventricles from the base to the apex. Acquisition was performed with end-expiratory breath-hold cine SSFP sequences. Several parameters such as end-diastolic and end-systolic volumes , stroke volume (SV), and ejection fraction (EF) of both ventricles were quantified using our automated segmentation method based on edge detection, iterative thresholding and region growing techniques  parameters using both methods (p>0.05). Correlation to estimate RV function (r>0.7) was slightly lower than that obtained for the left ventricle (r>0.9). Bland-Altman plots were used to assess the agreement between both methods.In conclusion, our automated segmentation method: provides similar results to those achieved by manual contour tracing, reduces both the time employed and the inter/intra-observer variability to a mouse click, and does not rely on a prior knowledge, providing a true segmentation of the anatomical features present in the image.


Cardiac MRI (CMR) provides unique characterization of myocardial injury post acute ST-Elevation Myocardial Infarction (STEMI). It is the gold standard for non-invasive measurement of Infarct Size (IS) and tissue perfusion during STEMI. Microvascular obstruction describes suboptimal tissue perfusion despite restoration of flow in the infarct-related artery (IRA). IS and MVO are independent predictors of adverse remodelling and prognosis post STEMI. MVO is generally assumed to be related primarily to reperfusion.per se.There is a paucity of data on the prevalence and extent of MVO in clinical practice using a range of different reperfusion methods, and in particular in those without reperfusion. We hypothesize that the extent and presence of MVO are primarily related to the extent of ischaemia than reperfusion 88 acute STEMI subjects were recruited over a 26-month period. 14 subjects were routine clinical CMR examinations undertaken in non-reperfused, late-presenting patients (>12 hours onset of symptoms) to assess viability. Subjects underwent assessment on a Siemens Avanto 1.5T system. Left ventricular function and volumes were assessed using SSFP. 10 minutes after intravenous injection of gadolinium contrast (0.2 mmol/kg), delayed contrast-enhanced images were acquired using a segmented inversion-recovery gradient-echo pulse sequence. IS was defined as areas of hyperenhancement with signal intensity (SI) >50% of peak SI in the infarct core . MVO was defined as hypointensity within areas of infarct.There were no significant differences in age, proportion of STEMI with left anterior descending artery (LAD) IRA, or gender in each of the reperfusion groups . Time from onset of symptoms to reperfusion was significantly longer in late PCI patients (p<0.0001). There was a trend towards larger IS in late PCI and rescue PCI, followed by those with no reperfusion. There was a trend towards larger extent of MVO in late PCI followed by no reperfusion and rescue PCI. Prompt thrombolysis resulted in a trend towards smallest IS and significantly lower extent of MVO. Chi-squared analysis demonstrated a trend towards higher prevalence of MVO in non-reperfused STEMI (75.0% v 61.1%).There is a higher prevalence and extent of myocardial and microvascular injury  in non-reperfused STEMI than in those undergoing timely reperfusion. MVO is not exclusive to reperfusion and may primarily represent the degree of ischaemic injury. This study suggests that rescue PCI and late PCI offer no reduction in IS or MVO compared with those undergoing no revascularisation.This study was funded by a British Heart Foundation research grant, with support from the University of Leicester Biomedical Research Unit.


Evidence suggests that adenosine acts via cardiac A1 adenosine receptors (A1ARs) to protect embryos against hypoxia. During embryogenesis, A1ARs are the dominant regulator of heart rate, and A1AR activation reduces heart rate. Adenosine action is inhibited by caffeine, which is widely consumed during pregnancy. In this study, we tested the hypothesis that caffeine influences developing embryos by altering cardiac function.in vitro using whole murine embryos at E9.5 and isolated hearts at E12.5. Embryos were examined in room air (21% O2) or hypoxic (2% O2) conditions. Hypoxia decreased heart rates of E9.5 embryos by 15.8% and in E12.5 isolated hearts by 27.1%. In room air, caffeine (200 µM) had no effect on E9.5 heart rates; however, caffeine increased heart rates at E12.5 by 37.7%. Caffeine abolished hypoxia-mediated bradycardia at E9.5 and blunted hypoxia-mediated bradycardia at E12.5. Real-time PCR analysis of RNA from isolated E9.5 and E12.5 hearts showed that A1AR and A2aAR genes were expressed at both ages. Treatment with adenosine receptor-selective antagonists revealed that SCH-58261 (A2aAR-specific antagonist) had no affects on heart function, whereas DPCPX (A1AR-specific antagonist) had effects similar to caffeine treatment at E9.5 and E12.5. At E12.5, embryonic hearts lacking A1AR expression (A1AR−/−) had elevated heart rates compared to A1AR+/− littermates, A1AR−/− heart rates failed to decrease to levels comparable to those of controls. Caffeine did not significantly affect heart rates of A1AR−/− embryos.Effects of caffeine and adenosine receptor-selective antagonists on heart rate were studied These data show that caffeine alters embryonic cardiac function and disrupts the normal cardiac response to hypoxia through blockade of A1AR action. Our results raise concern for caffeine exposure during embryogenesis, particularly in pregnancies with increased risk of embryonic hypoxia. Mature and developing mammals modulate cardiac output through alteration of heart rate and cardiac contractility In the embryo and fetus, hypoxia is a stressor with multiple etiologies that include placental insufficiency, maternal smoking, anemia, umbilical cord compression, pre-eclampsia, and living at high altitudes Adenosine is a crucial humoral mediator of functional changes induced by hypoxia Recent studies show that adenosine acts via A1ARs in the heart to protect embryos against hypoxia Caffeine is a multifunctional compound that influences intracellular calcium levels, inhibits phosphodiesterase activity, and blocks GABA receptors Considering that adenosine protects the embryo against hypoxia and that A1ARs are the dominant regulator of embryonic heart rate, we postulated that caffeine alters the normal embryonic cardiac response to hypoxia. To test this hypothesis, we examined responses to hypoxia and adenosine receptor blockade on embryonic cardiac activity at two ages spanning the critical period of cardiovascular morphogenesis, E9.5 and E12.5 To assess the effects of caffeine on embryonic heart function, whole embryos at E9.5 or isolated hearts at E12.5 were studied. At E9.5, the heart is at an early stage of cardiogenesis, corresponding to only one and a half days after the start of cardiac contractility in vivo using Doppler ultrasonography, or in situ via hysterectomy Before treatments, baseline heart rates were measured following a 1–2 h period. Mean baseline heart rates in the C57Bl/6 embryos were 109.2 beats per minute (BPM) at E9.5  and 124.2 BPM at E12.5 . There was a significant age-dependent increase in mean baseline heart rates (p = 0.0001). These values are similar to those observed for murine embryos studied in culture max and EC50. In the E12.5 hearts, caffeine treatment increased heart rates to an Emax of 38% above baseline levels (400 µM), with an EC50 of 118.4 µM , DPCPX caused significant elevations in heart rates that were more pronounced at E12.5 (67% increase) than at E9.5  of Yale University approved all experiments conducted on animals (protocol #2007-11136). The inbred mouse strain C57Bl/6  and A1AR-deficient mice (A1AR −/−) were studied 2. Embryonic age was determined by morphology and somite number 2 –room air incubator for 1–2 h prior to conducting tissue hypoxia studies and heart rate analyses.Embryos and hearts were cultured as described 2 exposure, C57Bl/6 embryonic tissues were cultured with 200 µM Hypoxyprobe-1 . Hypoxyprobe-1 forms protein adducts in O2 levels <10 mm Hg that can be detected by immunostaining 2 in a Plexiglass chamber  for 1 h or left in the incubator for 1 h for room air controls. O2 levels were maintained at 2% with a regulator (Biospherix) by introducing 95% nitrogen with 5% CO2 into the chamber. Chamber temperature was maintained between 35°C and 37°C with a heating cord. Tissues were fixed in 4% paraformaldehyde, embedded in paraffin, and sectioned. Conjugates were visualized with a monoclonal antibody to Hypoxyprobe-1  followed by a goat anti-mouse secondary antibody conjugated to Alexa488 , as described To assess if there was embryonic tissue hypoxia associated with 2% OUsing the chamber described above, heart rate measurements were performed through direct visualization with a dissecting microscope over 15-second intervals by a single individual who was blinded to treatment conditions. Measurements were performed in triplicate per sample at each time point.To generate concentration-response curves at E9.5 and E12.5 under normoxic conditions, individual specimens of the C57Bl/6 strain were treated with vehicle or increasing concentrations of caffeine . Six to 12 specimens were analyzed per experiment. Following a 1–2 h initial incubation period, the baseline heart rate for each specimen was measured. Individual specimens were treated with increasing concentrations of caffeine  or vehicle without changing the media, and heart rates were reassessed after 2 min. In addition, at E12.5, individual hearts were treated with vehicle or a single concentration of caffeine  to refine the concentration-response curves.Heart rates of C57Bl/6 embryos were assessed following hypoxia exposure and/or treatment with adenosine receptor antagonists. Cultures were treated with 200 µM caffeine. This concentration was selected based on our caffeine concentration-response data see . In addi2 level was selected based on our Hypoxyprobe-1 studies that showed increased tissue hypoxia while embryonic cardiac function was preserved. Heart rates were measured after 5 min in 2.0% O2 (t = 50 min) and 20 min in 2.0% O2 (t = 65 min). Finally, heart rates were reassessed after a 10 min recovery period in room air O2 (t = 100 min). In control experiments to show that embryonic heart function in culture is stable over time, heart rates were assessed at these time points without hypoxia or caffeine treatment.Heart rate experiments began after an initial 1–2 h incubation period following dissections. Plates containing 6–12 specimens were placed in the chamber and baseline heart rates were measured (time [t] = 0 min). Drugs or vehicle were added to each well in a blinded fashion and heart rates were reassessed after 5 min (t = 20 min). The chamber oxygen levels were lowered to 2.0%. This OEffects of caffeine and hypoxia on A1AR knockout mice was determined as described above for C57Bl/6 mice.5′- ATGACAAGAAAAAGCGGATG – 3′, reverse 5′ – CTTTTCTGCCTGTTTCCGTA – 3′; A1AR: forward 5′ – GTCCTGGTATGTGACCAAGC – 3′, reverse 5′ – CTGAGGCTCTGGGTGAACTA 3′; A2aAR: forward 5′ – GCAGAACGTCACCAACTTCT – 3′, reverse 5′ – ATGGCGATGTATCTGTCGAT – 3′; A2bAR: forward 5′ TGCATGCCATCAACTGTATC – 3′, reverse 5′ – TGGAAACTGTAGCGGAAGTC; A3AR: forward 5′ – AGCGAGCTCTCAAAATAGCA 3′, reverse 5′ – ATAAAATGCACGCGTCTCTC 3′) and were obtained from RealTimePrimers.com . Each real-time PCR experiment was performed in triplicate. PCRs were analyzed by mean normalized expression using Microsoft Excel, with Rp113a as the control gene. DNA contamination was assessed by a “no RT control” real-time PCR reaction, no DNA contamination was observed.Gene expression was determined for all four adenosine receptor subtypes in isolated hearts from E9.5 and E12.5 C57Bl/6 embryos, as described 50, defined as the drug concentration that caused heart rates to increase to levels halfway between baseline and maximum levels, was obtained from these curves where the lowest concentration corresponded to the addition of vehicle. The maximal mean increase in heart rate from basal levels was defined as Emax. Differences in response profiles over time between treatment or genotype groups were analyzed with repeated measures two-way ANOVA, differences within groups at different time points were analyzed with repeated measures one-way ANOVA, and differences in mean baseline heart rates were analyzed with unpaired Student's t-test assuming equal variances or one-way ANOVA. Bonferroni's tests were used for post hoc analyses. Data are presented as mean +/− the standard error of the mean (SEM). Two-tailed p<0.05 was considered to be statistically significant.Heart rates were measured in triplicate and recorded in a spreadsheet (Microsoft Excel) where average heart rate in beats-per-minute (BPM) were calculated. To standardize heart rates from all studies, heart rates were recorded as percent change from baseline using the formula: percent change = heart Rate/baseline×100. Descriptive statistics including 95% confidence intervals (CI) were calculated using Excel . Concentration-response curves were generated using GraphPad Prism version 5 . The EC


Purpose. The effects of mechanical ventilation (MV) on speckle tracking echocardiography- (STE-)derived variables are not elucidated. The aim of the study was to evaluate the effects of positive end-expiratory pressure (PEEP) ventilation on 4-chamber longitudinal strain (LS) analysis by STE. Methods. We studied 20 patients admitted to a mixed intensive care unit who required intubation for MV and PEEP titration due to hypoxia. STE was performed at three times: (T1) PEEP = 5 cmH2O; (T2) PEEP = 10 cmH2O; and (T3) PEEP = 15 cmH2O. STE analysis was performed offline using a dedicated software . Results. Left peak atrial-longitudinal strain (LS) was significantly reduced from T1 to T2 and from T2 to T3 (P < 0.05). Right peak atrial-LS and right ventricular-LS showed a significant reduction only at T3 (P < 0.05). Left ventricular-LS did not change significantly during titration of PEEP. Cardiac chambers' volumes showed a significant reduction at higher levels of PEEP (P < 0.05). Conclusions. We demonstrated for the first time that incremental PEEP affects myocardial strain values obtained with STE in intubated critically ill patients. Whenever performing STE in mechanically ventilated patients, care must be taken when PEEP is higher than 10 cmH2O to avoid misinterpreting data and making erroneous decisions. Echocardiography has become an indispensable diagnostic tool for the management of the critically ill patients in intensive care unit (ICU) . PatientThe standard echocardiographic parameters are not always easy to achieve in critically ill patients, due to the dependence on the angle of insonation. Furthermore, acquiring some unusual echocardiographic parameters can rise some difficulties by noncardiologists and not experienced operators , 6.Speckle tracking echocardiography (STE) is a new noninvasive ultrasound imaging technique that allows for an objective and quantitative evaluation of myocardial function, less dependent of the angle of insonation and of cardiac translational movements, compared to Doppler approaches –9. STE aTo our knowledge, in intubated patients no studies have been performed to evaluate the changes of myocardial strain induced by mechanical ventilation. Thus, the influence of PPMV with high levels of PEEP on STE-derived variables remains to be elucidated.The aim of the study was to evaluate the effects on the longitudinal strain (LS) of the four cardiac chambers at different levels of PEEP.2), the presence of preexisting myocardial akinesia, not sinus rhythm, severe mitral or aortic regurgitation or stenosis and ascending aortic diseases, mitral stenosis, any prosthetic mitral and/or aortic valve, and an insufficient imaging quality of the endocardial border.We performed a prospective observational study at the mixed Intensive Care Unit (ICU) of the University Hospital of Siena. Approval from the institutional review board was obtained, along with written informed consent from patients or their legal representative. We enrolled 20 consecutive patients , admitted to our ICU due to heterogeneous pathologies, who needed intubation for mechanical ventilation. Inclusion criteria were hypoxia requiring PEEP levels optimization, invasive arterial pressure monitoring, and age > 18 years. Exclusion criteria were the presence of active air leak  and chronic obstructive bronchopneumopathy, intracranial pressure > 20 mmHg, hemodynamic instability .Patients were sedated with propofol 2% (0.5–2 mg/kg/hr) or midazolam (0.5–2 mg/kg/hr) and fentanyl (0.5–1 mcg/Kg/hr). All of them were equipped with a radial arterial catheter and a central venous catheter. Patients were ventilated on volume controlled mechanical ventilation  until reaching the best oxygenation with minimal negative hemodynamic effects. Measurements were performed after 5 minutes of stable mean arterial pressure and under haemodynamic steady-state conditions (about 10 minutes after having reached each level of PEEP). At each time of study a second operator measured the parameters of respiratory mechanics: intrinsic PEEP , plateau pressure (Pplat), peak pressure (Ppeak), TV, RR, and static compliance of the respiratory system (Crs) were calculated using the standard formula. At the same time, a third operator estimated various hemodynamic parameters  using the pulse contour method MostCare  [Standard echocardiography  was performed by the same operator for each patient after having increased PEEP three times: T1 = 5 cmH, Italy) –19. STE Echocardiography was performed using a high-quality echocardiograph . Patients were studied in the supine position. Bidimensional and Doppler measurements were made in accordance with current recommendations of the American Society of Echocardiography . Left veFor speckle tracking analysis, apical four- and two-chamber and apical long-axis view images were obtained using conventional two-dimensional grayscale echocardiography, with a stable ECG recording. Particular attention was given to obtain an adequate gray scale image, allowing reliable delineation of myocardial tissue and extracardiac structures. For measurements, three consecutive heart cycles were recorded and averaged. The frame rate was set between 60 and 80 frames per second. These settings are recommended to combine temporal resolution with adequate spatial definition and to enhance the feasibility of the frame-to-frame tracking technique . RecordiGlobal longitudinal strain was defined by averaging longitudinal peak strain measured in apical 4- and 2-chamber and apical long-axis views.The right ventricular-longitudinal strain (RV-LS) was calculated by averaging values observed in all RV segments .Peak atrial longitudinal strain (PALS) was calculated by averaging values observed in all LA and RA segments  and by averaging values observed in 4- and 2-chamber views (4- and 2-chamber average PALSs). Care was taken to obtain accurate apical images using standard anatomic landmarks in each view and not foreshorten the atrial chambers, allowing a more reliable delineation of the atrial endocardial border. TPLS was also measured as the average of all 12 segments  and by separately averaging values observed in the two apical views (4- and 2-chamber average TPLSs). In patients in whom some segments were excluded because of the impossibility of achieving adequate tracking, ventricular-longitudinal strain, PALS, and TPLS were calculated by averaging values measured in the remaining segments.The reproducibility and the feasibility of STE measurements of 4-chamber longitudinal strain have been previously reported , 16.Statistical analysis was performed using the software SPSS 17.0 . To test the normal distribution of the data the Kolmogorov-Smirnov test was used. Statistical differences were verified by one-way ANOVA. All data are presented as mean ± standard deviation (SD) or number and percentage when appropriate.2O [s into four quadrant plot graphs [P value less than 0.05 was considered statistically significant.In order to investigate the potential interrelation between the variables , we performed the Pearson's correlation test for changes over time (Δ) of the variables. Changes of (Δ) in size, strain, and stroke volumes were calculated by subtracting the first from the third value . Furthermore, to account for the effect of changes in size and strain values on stroke volume, patients were divided into two groups according to their reduction in SV  after having increased PEEP from 5 to 15 cmH2O . Finallyt graphs , 28. A P2O (P < 0.05) and CO did the same . Cardiac chambers volumes  showed a significant reduction with incremental PEEP  (P < 0.05) (P < 0.05)   showed a greater reduction in LV-EDV and LAV than those with an SV reduction > 15%   . LV-EF,  < 0.05) . LA-PALS < 0.05) . RA-PALS < 0.05) . Convers < 0.05) . Compari > 0.05) . All pat = 0.05) . Changes = 0.05) .The major finding of this study is a significant reduction of left atrial-, right atrial-, and right ventricular-longitudinal strain values during the increase of PEEP levels. Conversely, left ventricular-longitudinal strain values did not show significant changes. To our knowledge, this is the first study that evaluates the influence of different levels of PEEP on 4-chamber longitudinal strain obtained by STE in intubated patients.The use of echocardiography is increasing in critically ill patients, for evaluating either the cardiac function or the potential negative effects of mechanical ventilation on the cardiovascular system. The latter is particularly important in patients with severe respiratory failure, such as acute respiratory distress syndrome (ARDS), in whom the usage of very high levels of PEEP is usual , 4, 29.Although physicians have gained familiarity with “rummy echocardiographic data” that are frequently observed in intubated patients ventilated with PEEP, some potential limitations with the use of echocardiography in critically ill patients still remain: firstly, there could be a certain difficulty to obtain some angle-dependent parameters in mechanically ventilated patients in the supine position , 6; secoSTE is based on an analysis of the spatial dislocation (referred to as tracking) of speckles  on routine 2-dimensional sonograms . By tracIn general, STE may allow an evaluation of myocardial systolic and diastolic dynamics across a broad range of physiologic and pathologic conditions beyond traditional echocardiographic techniques. Indeed, valuable strain values have been obtained in pathologic conditions as hypertension, diabetes, heart failure, coronary artery disease, and cardiac dyssynchrony and after heart transplantation –16.Although STE may have some advantages over standard echocardiography , misleading interpretation of STE-derived data may occur in intubated patients, and the potential effects of PPMV + PEEP on such parameters have not yet been elucidated and codified. The mechanisms by which the PEEP alters the hemodynamic status of patients are complex and are also influenced by pathologies of the respiratory system . The main hemodynamic effect of PEEP is the impairment of cardiac function related to lung volume and intrathoracic pressure (ITP) changes . Briefly2O. In other words, we found that the higher the PEEP, the lower the LA- and RA-PALS and RV-LS. Conversely, LV-LS did not change significantly with incremental PEEP , and whose reduction occurs before deterioration of LV-EF . Experimental studies have shown that although CO is affected by incremental PEEP many indices of LV contractility, such as LV-EF, end systolic indices, and dP/dt are not –39. The By increasing PEEP, RV-EDD increased significantly and RV-LS showed a significant reduction , althougSome limitations have to be taken into account whenever using STE in critically ill patients undergoing mechanical ventilation. Primarily, as for traditional echocardiography, an adequate apical view is required to get different data. However, some studies have shown that an apical view is feasible in the majority of intubated patients , 12, 42.Some limitations of our study have to be addressed. The small sample size did not allow us to explore the changes of myocardial strain associated with PEEP in patients with very poor lung compliance. In addition, to confirm the hypothesis that volume status can influence the changes in cardiac chambers strain induced by high levels of PEEP, it would have been useful to perform a fluid challenge. However, the present paper is an observational study, and the decision of administrating fluids was based on physicians' judgment, according to the needs of the single patient. Finally, it would have been more informative having performed STE in the same patients after extubation, in order to assess how STE-derived variables would have changed by shifting mechanical ventilation to spontaneous breathing.In critically ill patients undergoing mechanical ventilation with PEEP, LA-, RA-PALS, and RV-LS significantly decrease related to incremental PEEP. Conversely, LV-LS remains stable demonstrating that the reduction of CO that occurs with incremental PEEP is preload-related and not contractility-related. 2O to avoid misinterpreting data and making erroneous decisions. Further studies are warranted to confirm our results in an independent cohort.Whenever performing STE and interpreting the myocardial strain values in mechanically ventilated patients to guide therapy, the physician should be aware that high levels of PEEP might influence STE-derived variables at a different degree. Specifically, care must be taken when PEEP is higher than 10 cmH


Trials of iron chelator regimens have increased the treatment options for cardiac siderosis in beta-thalassemia major (TM) patients. Treatment effects with improved left ventricular (LV) ejection fraction (EF) have been observed in patients without overt heart failure, but it is unclear whether these changes are clinically meaningful.This retrospective study of a UK database of TM patients modelled the change in EF between serial scans measured by cardiovascular magnetic resonance (CMR) to the relative risk (RR) of future development of heart failure over 1 year. Patients were divided into 2 strata by baseline LVEF of 56-62%  and 63-70% .A total of 315 patients with 754 CMR scans were analyzed. A 1% absolute increase in EF from baseline was associated with a statistically significant reduction in the risk of future development of heart failure for both the lower EF stratum  and the higher EF stratum .These data show that during treatment with iron chelators for cardiac siderosis, small increases in LVEF in TM patients are associated with a significantly reduced risk of the development of heart failure. Thus the iron chelator induced improvements in LVEF of 2.6% to 3.1% that have been observed in randomized controlled trials, are associated with risk reductions of 25.5% to 46.4% for the development of heart failure over 12 months, which is clinically meaningful. In cardiac iron overload, heart mitochondrial dysfunction and its relief by iron chelation may underlie the changes in LV function. Major advances have been made in the last 10 years in the understanding and treatment of cardiac siderosis in beta-thalassaemia major (TM) patients. Those advances are attributable primarily to the development of a method for the quantification of myocardial iron based on magnetic resonance T2* imaging and its worldwide adoption,,4the estEthical permission was obtained from the research ethical committee for this study. A database of 652 patients from 21 UK haematology centres was established and maintained prospectively, as previously reported. We apprPatients were scanned with a 1.5T scanner  using previously reported techniques. In brieAll statistical analyses were performed by a medical statistician. Two categories of baseline EF were used in this analysis; 56-62% and 63-70%. These strata were used because 63% is the lower limit of normal for EF in thalassemia patients in the absence of myocardial siderosis, and 56% A total of 315 patients satisfied the selection inclusion criteria, who had undergone 754 CMR scans. There were 12 HF events in the 56-62% LVEF cohort and 14 in the 63-70% LVEF cohort. This equals an event rate of 11.0% and 6.8% respectively. Analysis of the occurrence of heart failure showed a relative risk of 0.818 (p < 0.001) for the stratum of patients with baseline EF 56-62%, which represents an 18.2% reduction in risk for each 1% increase in EF  or with an intrinsic ability of a chelator to associate with cell components such as membranes or proteins and thereby become retained in cells. Prolonged retention in cells can also be deleterious as a chelator can interfere with the biosynthetic machinery of heme or iron-S-clusters, and in extreme conditions could drive cells into an apoptotic path-77. On tAnalysis of a large TM database showed that small changes in ejection fraction have statistically significant and clinically meaningful effects in reducing the important clinical outcome of heart failure. These data suggest that the results from randomized controlled trials using deferiprone in TM yield a 40.7% to 46.4% relative risk reduction for heart failure in patients with a baseline ejection fraction below normal of 56-62%, and a 25.5% to 29.6% relative risk reduction for heart failure in patients with normal baseline ejection fraction of 63-70%. These predicted improved outcomes are consistent with several reports of reduced heart disease and increased survival in transfusion-dependent patients treated with deferiprone, lending support to the predictive value of improvement in clinical outcome as a consequence of increasing LVEF. The data indicate that prognostically important subclinical LV dysfunction can occur in TM patients with cardiac iron overload whilst EF remains in the lower normal range. The most likely explanation for the improvement in LV function found in the randomized controlled trials using deferiprone, is improved myocardial mitochondrial function although the exact mechanisms remain to be fully elucidated.Dr Pennell is a consultant to Siemens, Novartis and Apotex, and has received research support and speaker's honoraria. He is a director of Cardiovascular Imaging Solutions. John-Paul Carpenter and Michael Roughton have no conflicts to declare. Dr Cabantchik has received research support and speaker's honoraria from Novartis and Apotex.DJP conceived the study and wrote the manuscript. JPC was responsible for data collection. MR performed the statistical analysis. IZC assisted in interpretation of the results and basic science discussion of mitochondria. All authors read and approved the final manuscript.