Patent arterial duct (PAD) is a congenital heart abnormality defined as persistent patency in term infants older than three months. Isolated PAD is found in around 1 in 2000 full term infants. A higher prevalence is found in preterm infants, especially those with low birth weight. The female to male ratio is 2:1. Most patients are asymptomatic when the duct is small. With a moderate-to-large duct, a characteristic continuous heart murmur (loudest in the left upper chest or infraclavicular area) is typical. The precordium may be hyperactive and peripheral pulses are bounding with a wide pulse pressure. Tachycardia, exertional dyspnoea, laboured breathing, fatigue or poor growth are common. Large shunts may lead to failure to thrive, recurrent infection of the upper respiratory tract and congestive heart failure. In the majority of cases of PAD there is no identifiable cause. Persistence of the duct is associated with chromosomal aberrations, asphyxia at birth, birth at high altitude and congenital rubella. Occasional cases are associated with specific genetic defects . Familial occurrence of PAD is uncommon and the usual mechanism of inheritance is considered to be polygenic with a recurrence risk of 3%. Rare families with isolated PAD have been described in which the mode of inheritance appears to be dominant or recessive. Familial incidence of PAD has also been linked to Char syndrome, familial thoracic aortic aneurysm/dissection associated with patent arterial duct, and familial patent arterial duct and bicuspid aortic valve associated with hand abnormalities. Diagnosis is based on clinical examination and confirmed with transthoracic echocardiography. Assessment of ductal blood flow can be made using colour flow mapping and pulsed wave Doppler. Antenatal diagnosis is not possible, as PAD is a normal structure during antenatal life. Conditions with signs and symptoms of pulmonary overcirculation secondary to a left-to-right shunt must be excluded. Coronary, systemic and pulmonary arteriovenous fistula, peripheral pulmonary stenosis and ventricular septal defect with aortic regurgitation and collateral vessels must be differentiated from PAD on echocardiogram. In preterm infants with symptomatic heart failure secondary to PAD, treatment may be achieved by surgical ligation or with medical therapy blocking prostaglandin synthesis (indomethacin or ibuprofen). Transcatheter closure of the duct is usually indicated in older children. PAD in preterm and low birth weight infants is associated with significant co-morbidity and mortality due to haemodynamic instability. Asymptomatic patients with a small duct have a normal vital prognosis but have a lifetime risk of endocarditis. Patients with moderate-to-large ducts with significant haemodynamic alterations may develop irreversible changes to pulmonary vascularity and pulmonary hypertension. Persistence of the arterial duct has been defined as continued patency in term infants older than 3 months . It can et al. .et al. [Isolated patent arterial duct is found in around 1 in 2000 full term infants, constituting nearly 10% of all congenital heart disease  and is tet al.  reportedet al. -10. Theret al. . The famet al. .Most patients are asymptomatic . In a moderate-to-large duct, the patency of the arterial duct is recognised on detection of the characteristic continuous heart murmur. Often termed a "machinery murmur", this is typically loudest at the left upper chest or infraclavicular area. The precordium may be hyperactive and peripheral pulses are bounding with a wide pulse pressure. The patient may have tachycardia and in older children there may be a history of exertional dyspnoea. There may be history of prematurity, asphyxia, or maternal rubella. The baby may have fast or laboured breathing, become tired easily, or display poor growth. Large shunts may lead to failure to thrive, recurrent infection of the upper respiratory tract and congestive heart failure . There iIn premature infants, there should be a high index of suspicion. Often ventilated infants with hyaline membrane disease will improve followed by an inability to wean ventilation or require increased support. There may be episodes of apnoea, bradycardia or general cardiovascular instability. Physical examination may be similar to older children with tachycardia, a continuous murmur and bounding pulses however it is not uncommon for the murmur to be only systolic.In patients where a moderate-to-large patent duct has not been previously diagnosed, irreversible pulmonary vascular changes may occur secondary to prolonged exposure of high pulmonary flow and pressure. These changes include arteriolar medial hypertrophy, intimal proliferation and fibrosis. In this group of patients when pulmonary arterial pressure exceeds systemic pressure, the flow across the duct is reversed and is right to left. This results in the patient becoming cyanosed which may be differential with cyanosis and possibly clubbing seen in the feet but not the fingers. The murmur may disappear with accentuation of the second heart sound as a result of high pulmonary pressure. These patients will have a progressive reduction in their exercise capacity.th week of fetal life. The duct normally constricts shortly after birth due to the postnatal drop in circulating prostaglandin E2 levels, as well as the rise in systemic oxygen tension, which induce a cytochrome P450-dependent increase in endothelin-1 in ductal smooth muscle cells [The arterial duct is the arterial connection between the pulmonary artery and the aorta that shunts blood away from the lungs during fetal life. In normal cardiovascular embryological development the arterial duct is formed from the sixth pair of embryonic arches. The distal portion of the left sixth arch persists as the arterial duct, connecting the left pulmonary artery with the left dorsal aorta with regression of the right distal arch. This process is completed by the 8le cells . Subsequle cells .In a term infant with a patent arterial duct, the structure of the ductal wall is abnormal. Histologically, the internal elastic lamina of the arterial duct is generally intact and the internal cushions are absent or less well formed than usual . In the TT genotype of MTHFR C677T locus involved in homocysteine metabolism [In the majority of cases of patent arterial duct there is no identifiable cause. These cases represent the influence of multifactorial inheritance . Persisttabolism , althougOccasional cases are associated with specific genetic defects. These include chromosomal defects, such as trisomy 21 and 18, deletion syndromes 4q-, 16p13.13 (Rubinstein-Taybi) and 9p- (CHARGE). Issekutz's epidemiological study looking at infants diagnosed with CHARGE syndrome in Canada demonstrated a higher incidence of patent arterial duct in subgroup B, who present with only three or fewer major criteria . FamiliaFamilies with a high incidence of persistent patency of the arterial duct have been reported by several researchers ,20-23. Iet al. described a family in which four out of six children of the same family were affected with patent arterial duct [e.g. maternal rubella, maternal alcohol abuse, and high altitude) could be excluded from this case.Wei ial duct . Their pet al. found that patent arterial duct accounted for 15% of congenital heart disease in Iran, compared to 2%–7% in the United States [Mani d States . MoreoveChar syndrome is an autosomal dominant condition comprising ptosis, low-set ears, short philtrum and 'duck-bill' lips, patent arterial duct, a single fifth finger flexion crease with two fifth finger phalanges and mild learning difficulties. Other features described include a broad forehead, flared eyebrows, mild hypertelorism, flat midface and strabismus. First described by Char in 1978, this syndrome has subsequently been reported by several subsequent investigators -29. The TFAP2B, encoding a neural crest-related transcription factor . The TFAP2 genes play an important role in retinoic acid-induced differentiation, particularly in cells derived from the neuroectoderm. Thus, it appears that the patent arterial duct in Char syndrome is likely a result of abnormal neural crest development [Char syndrome has been mapped to a narrow region of chromosome 6p12-p21 . Furtherelopment .et al. described a single large three-generational French family with a vascular syndrome that associates TAA/AD with patent arterial duct [MYH11 gene were eventually identified, which encodes the smooth muscle myosin heavy chains, however this is only thought to be involved in rare instances in sporadic instances of patent duct [et al. and Telen et al. [Khau Van Kien ial duct . Geneticial duct . Mutatioent duct . The modn et al. ,35. The A novel inherited syndrome has recently been described comprising variable cardiovascular defects , hand anomalies , and generalised brachydactyly. Linkage analysis with this moderate-sized kindred using polymorphic DNA markers from the Char syndrome locus excluded the possibility that this family was inheriting an allelic variant of Char syndrome. Inspection of the pedigree favoured inheritance by a dominant mechanism. However, X-linked dominance could not be excluded. Penetrance appeared to be complete, but there was variability in the cardiac and hand phenotypes .Diagnosis is usually possible based on clinical examination. The confirmation of a patent arterial duct is made with transthoracic echocardiography. In the majority of cases, cross sectional echocardiography can accurately define the presence and characteristics of a patent arterial duct. The most commonly employed views are left parasternal, high left parasternal, suprasternal and short axis views . The artet al. [Diagnostic cardiac catheterisation with angiography is rarely necessitated in patients with typical clinical and echocardiographic findings. Predominately catheterisation is limited to transcatheter therapies for occlusion of the duct. In this setting, ductal anatomy is usually defined with aortography Figure . The conet al. . The TypThere have been significant advances in the understanding and identification of genetic causes of congenital heart disease in the last decade and continues to be a field which is changing rapidly . The recAntenatal diagnosis of patent arterial duct is not possible as it is a normal structure during antenatal life. At present, there are no antenatal genetic investigations that can reliably predict the patency of the arterial duct in postnatal life.Conditions in which there are signs and symptoms of pulmonary over circulation secondary to a left to right shunt must be excluded. Other conditions may also present with a continuous murmur and bounding pulses and differentiation from an arterial duct must be made on echocardiogram. These include: coronary, systemic and pulmonary arteriovenous fistula, collateral vessels, peripheral pulmonary stenosis and ventricular septal defect with aortic regurgitation .Preterm infants with symptomatic heart failure secondary to persistent patency of the arterial duct may be treated by surgical ligation or medically with conservative management and indomethacin or ibuprofen. Medical intervention is usually the treatment of choice due to the risks involved with surgical ligation. Initial conservative management involves fluid restriction and diuretic therapy with optimisation of calorie intake and ventilator support. These actions will not aid ductal closure but can improve respiratory physiology and symptoms in the short term. Indomethacin and ibuprofen act as inhibitors of prostaglandin forming cyclo-oxygenase (COX) enzymes. No statistical difference has been demonstrated between ibuprofen and indomethacin in their effectiveness in closing a patent duct . IndometA number of infants will either not be suitable or fail medical management. These include infants with renal impairment, gastrointestinal pathology including previous necrotising enterocolitis and patients with platelet dysfunction. In such cases, surgical division and ligation is indicated for closure of a significant arterial duct. This is performed via a thoracotomy and whilst high closure rates and low mortality are reported there may be significant morbidity. These include bleeding, pneumothorax, chylothorax, infection, haemodynamic instability and thoracic scoliosis. A minimally invasive surgical approach employing video-assisted thoracic surgery (VATS) has shown early results comparable to thoracotomy including premature and low birth weight infants ,52.In children outside of this age group, the management decisions are based on the control of symptomatic pulmonary over circulation and the lifetime risk of endocarditis. Transcatheter closure of the duct is usually offered to all children outside of the neonatal period. There have been several studies reporting excellent results with low complication rates for a variety of occluders Figure , 5 53-5-553-56. The best management for the 'silent' duct remains debatable with many centres electing not to close either surgically or via catheter techniques. The risk of endocarditis is low, although studies have reported an increase in the incidence in these patients . This haThe prognosis for the untreated patent arterial duct depends largely on the size of the duct and the degree of left to right shunt and pulmonary over circulation. In preterm and low birth weight infants a patent duct is associated with significant co-morbidity and mortality due to haemodynamic instability. These include pulmonary oedema and haemorrhage, bronchopulmonary dysplasia, intraventricular haemorrhage necrotizing enterocolitis as well as congestive cardiac failure. Patients with a small duct may exhibit no symptoms and have no haemodynamic impairment, these patients have a normal prognosis but do have a lifetime risk of endocarditis. Those patients with moderate-to-large ducts with significant haemodynamic changes may present with evidence of congestive cardiac failure or in the long term may develop irreversible changes to pulmonary vascularity and pulmonary hypertension . PatientFor patients who undergo transcatheter closure the immediate occlusion rates are in excess of 90% and immediate complication rates are low -56,60,61Surgical ligation and division of the arterial duct has been shown to have excellent results although is more invasive than transcatheter techniques. It remains an important treatment option for arterial ducts which are unsuitable for transcatheter closure and in premature infants in which medical management has failed. Occlusion rates are in excess of 95% with mortality figures 1–2% . Once thThe authors declare that they have no competing interests.JF wrote the first draft of the manuscript. All authors revised the manuscript, read and approved the final manuscript.


The retrograde atrial activation sequence constitutes an initial important clue to elucidate the tachycardia mechanism during diagnostic electrophysiological testing in patients with supraventricular tachycardia. However, in some cases its correct analysis is challenging. A 19-year-old man with a two-year history of frequent episodes of symptomatic drug-refractory paroxysmal supraventricular tachycardia was referred to our institution for catheter ablation. The patient had no structural heart disease and baseline ECG showed normal sinus rhythm with no evidence of preexcitation. An electrophysiological study was performed using standard techniques in the fasting state. A 7 Fr steerable quadripolar catheter was placed in the coronary sinus (CS) with distal bipole located at the posterolateral region of the CS. Standard quadripolar catheters were placed in the right ventricular apex, the His bundle position and the high right atrium. The baseline conduction intervals were normal with sinus cycle length, atrial-His (AH), and His-ventricular (HV) intervals of 868, 73, and 50 ms, respectively. Dual AV nodal physiology was demonstrated anterogradely but not retrogradely. The earliest retrograde atrial activity during ventricular pacing was in the His bundle recording. Programmed atrial stimulation induced a short RP supraventricular tachycardia with a cycle length of 370 ms  after an The tachycardia exhibited a retrograde atrial activation sequence with the earliest activity recorded in the region of the His. The differential diagnosis of this paroxysmal supraventricular tachycardia includes atrioventricular nodal reentrant tachycardia, orthodromic atrioventricular reentrant tachycardia using a concealed septal accessory pathway and atrial tachycardia. Typical atrioventricular nodal reentrant tachycardia and atrial tachycardia can be ruled out by the observation of a septal VA interval greater than 70 ms during tachycardia  and by VMapping of the tricuspid annulus revealed a long VA interval, with the earliest atrial activation in the right anteroseptal region. This finding along with the inability to preexcite the atrium by ventricular extrastimuli delivered when the His bundle was refractory suggested us the remote possibility of the existence of a left-sided non-septal accessory pathway associated to intra-atrial conduction block (or delay) along the mitral isthmus. To explore such an option a 5 Fr decapolar catheter (2-8-2-mm interelectrode spacing) was placed in the coronary sinus with the distal electrode in the region of the anterolateral mitral annulus. Tachycardia was again induced by ventricular pacing and an eccentric retrograde atrial activation sequence with the earliest atrial activity recorded at the lateral aspect of the mitral annulus was demonstrated . TherefoWe used the retrograde transaortic approach for mitral annulus mapping and it revealed the shortest VA interval at the lateral aspect of the mitral annulus . The accBlock of the mitral-pulmonary isthmus related to ablation of left-sided accessory pathway causing different patterns of retrograde atrial activation (from eccentric to concentric) has been previously reported ,4 but toThe present case shows two interesting aspect: a) intrinsic conduction block (or delay) non-related to prior ablation in the mitral isthmus might exist to some extent in some patients; and b) conduction block in the mitral isthmus in the presence of a laterally located left-sided accessory pathway may alter the atrial activation sequence during either orthodromic atrioventricular reentrant tachycardia or ventricular pacing conducting through the accessory pathway . A detai


The systolic dyssynchrony index (SDI) has been introduced as a measure of mechanical dyssynchrony using three-dimensional echocardiography to select patients who may benefit from cardiac resynchronization therapy (CRT). However, three-dimensional echocardiography may be inadequate in a number of patients with suboptimal acoustic window and no single echocardiographic measure of dyssynchrony has proven to be of value in selecting patients for CRT. Thus, the aim of this study was to determine the value of cardiovascular magnetic resonance (CMR) for the assessment of the SDI in patients with reduced LV function as well as in healthy controls using semi-automatic border tracking.We investigated a total of 45 patients including 35 patients (65 ± 8 years) with reduced LV function (EF 30 ± 11%) and a wide QRS complex as well as 10 control subjects . For cine imaging a standard SSFP imaging sequence was used with a temporal resolution of 40 frames per RR-interval. Quantitative analysis was performed off-line using a software prototype for semi-automatic border detection. Global volumes, ejection fraction and the SDI were calculated in each subject. SDI was compared with standard echocardiographic parameters of dyssynchrony.The mean SDI differed significantly between patients (14 ± 5%) and controls . An exponential correlation between the EF and the SDI was observed . In addition, a significant association between the SDI and the standard deviation of time to peak systolic motion of 12 LV segments (Ts-SD) determined by echocardiography was observed .The results of this preliminary study suggest that CMR with semi-automatic border detection may be useful for the assessment of mechanical dyssynchrony in patients with reduced LV function.No trial registration due to recruitment period between October 2004 and November 2006 Several studies have shown that the presence of intra-left ventricular (LV) dyssynchrony is one of the main predictors of response to cardiac resynchronization therapy (CRT) -3. The sMore recently volumetric real time three-dimensional echocardiography has been used in conjunction with semi-automatic border detection algorithms to evaluate heart-failure patients for the presence of mechanical asynchrony ,11. MyocThus, the primary aim of this study was to compare the SDI in patients with reduced LV function and in healthy controls using cine CMR and semi-automatic border detection algorithms.The study group of this feasibility study consisted of 45 subjects including 35 heart failure (HF) patients  with reduced systolic LV function (EF 30 ± 11%) and wide QRS complex ≥ 120 ms (mean QRS duration 158 ± 22 ms). Ten normal subjects without cardiac disease  with normal QRS duration (83 ± 5 ms on electrocardiogram) were evaluated for comparison. The inclusion criteria for the HF patients were as follows: 1) heart failure New York Heart Association (NYHA) class III or IV 2) known ischemic (n = 13) or non-ischemic cardiomyopathy (n = 22) with at least a moderately impaired LV function (EF ≤ 40%) as assessed by CMR and 3) wide QRS complex ≥ 120 ms with left bundle branch block or interventricular conduction delay. Patients with acute coronary syndromes were excluded from the study. The patients were recruited between October 2004 and November 2006.The ischemic or non-ischemic etiology of the cardiomyopathy was assessed using invasive cardiac catheterization. We performed cine CMR in all patients and control subjects. In addition, we retrospectively analysed echocardiographic data of the HF patients.Informed consent was obtained from each patient prior to the investigation in accordance with local Ethics Committee requirements.2, slice thickness 8 mm) was used with a temporal resolution of 40 frames per RR-interval. Three long-axis images and a stack of 10 to 12 short axis images covering the complete LV were acquired.Cine CMR was performed on a 1.5 T whole-body MR scanner  with electrocardiographic gating. Images were obtained using a five element cardiac synergy coil during repeated breath-holds (approximately 7 to 15 seconds). For cine imaging a standard SSFP imaging sequence (imaging parameters: echo time (TE) 1.8 ms, repetition time (TR) 3.6 ms, spatial resolution 1.8 × 1.5 mmThe data set was transferred to a separate workstation and reconstructed off-line to a 4D volume data set. Quantitative analysis was performed using a software prototype for semi-automatic border detection . Endocardial borders were manually outlined in the three long-axis images at end-diastole and end-systole. Based on these initial contours LV casts are automatically calculated for each of the 40 time frames per RR interval providing a global volume-time-curve. Manual editing of endocardial borders in selected short-axis slices was possible. These changes in 2D images were subsequently adopted in the 3D data set. The cast were automatically subdivided into 17 subsegments resulting in 17 segmental volume-time curves  in 32 of 35 (91%) HF patients. These patients received a comprehensive echocardiographic study using a commercially available ultrasonographic system . Interventricular mechanical dyssynchrony was assessed by determination of aortic and pulmonary pre-ejection times. A difference of more than 40 ms between the pulmonary and the aortic pre-ejection times (dPEP) was considered as significant delay . For assContinuous variables are expressed as mean values ± standard deviation. Categorical data are presented as frequencies for the study population as well as for the control group and were compared using the Chi-Square test. The unpaired Student's t test was used for comparisons of continuous variables, i.e. for comparison of the ejection fraction, LV volume and SDI between patients and control subjects. The degree of association between SDI and EF as well as between SDI and echocardiographic parameters of asynchrony  was investigated by computing the Pearson's correlation coefficient. In addition, intraobserver and interobserver correlations were evaluated by using the Pearson's correlation coefficient.Intraobserver variability of SDI was derived from manually outlined endocardial borders in the three long-axis images at end-diastole and end-systole from CMR of 10 randomly selected patients. Studies were performed by the same observer on 2 occasions 3 weeks apart. Interobserver variability was derived from the same subjects, performed by two blinded observers. Both intra- and interobserver variabilities were calculated as the standard deviation of the absolute difference between 2 measurements divided by the mean of both measurements, and expressed as a percentage. In Bland Altman analyses, the intraobserver and interobserver agreements, expressed in terms of the mean difference ± 2 standard deviation were evaluated.The global significance level for all statistical tests conducted was chosen to α = 0.05. Statistical analysis was performed with the use of SPSS 10.0 .The clinical baseline characteristics of the patient population with heart failure and the healthy control subjects are demonstrated in Table Data analysis using the semi-automatic software was feasible in all patients. Manual correction of endocardial contours had to be performed in most of the patients n = 39, 87%). The mean time required for complete analysis was 10 minutes. However, major corrections defined by an additional time required for manual editing of endocardial borders in selected short-axis slices > 5 minutes (range 6–15 minutes) were needed in only a smaller proportion of patients n = 10, 22%). Eight (80%) of these patients belonged to the HF group. In patients with HF the EF was significantly lower (EF 30 ± 11%) compared to the control subjects . In addition, LVEDV and LVESV measured by CMR were larger in HF patients than in controls  were 0.02  and 0.16 (-3.45 to 3.77%), respectively.A significant association between the SDI assessed by CMR and the standard deviation of time to peak systolic motion of 12 LV segments (Ts-SD) determined by Tissue Doppler imaging was observed (r = 0.66, p = 0.002, n = 20, Fig. The results of this preliminary study show that myocardial wall motion can be quantified by volume-time curve analysis for assessment of mechanical dyssynchrony using CMR with semi-automatic border detection in analogy to 3D echocardiography. Using 3D imaging techniques it is possible to integrate the function of all 17 segments into the SDI which can be used to quantify the severity of LV dyssynchrony.There is currently no gold-standard for the assessment of LV dyssynchrony. As electrical dyssynchrony does not accurately reflect intra-LV dyssynchrony, QRS-duration was found to be a poor predictor of CRT long term response ,15. VentReal time 3D echocardiography has been shown to provide a precise evaluation of LV volumes even in conditions of altered load . KapetanAs no single echocardiographic measure of dyssynchrony has proven to be of value in selecting patients for CRT , CMR mayIn this CMR study a semi-automatic border detection prototype for quantitative analysis of LV dyssynchrony was used. The SDI values for normal subjects as well as for patients with HF in this study are in excellent agreement to previously published data using real-time 3D echocardiography . In addiThe study population was relatively small. In addition, we did not assess a potential influence of infarct related wall thinning or motion abnormality on the calculation of the SDI. Thus, further prospective studies in larger populations also in comparisons to other imaging modalities are required to confirm this methodology to assess LV dyssynchrony and to compare with patient outcome.The results of this feasibility study suggest that CMR with semi-automatic border detection may be useful for the assessment of mechanical dyssynchrony in patients with reduced LV function.The authors declare that they have no competing interests.RK conceived and designed the study, analyzed the data and drafted the manuscript. MN operated the CMR scanner and helped draft the manuscript. GS stored the data and participated in analyzing the CMR data. GAK operated the CMR scanner and helped draft the manuscript. SS performed the statistical analysis. RWG and MK participated in study design, coordination and scientific input. HPK participated in analysing the CMR data as well as in scientific input. All authors read and approved the final manuscript.


Dynamic intraventricular obstruction has been observed in patients with left ventricular ballooning syndrome (LVBS) and has been hypothesized as a possible mechanism of the syndrome. The aim of this study was to assess the prevalence and significance of dynamic intraventricular obstruction in patients with LVBS.Dobutamine stress echocardiography was carried out in 22 patients with LVBS , all women, aged 68 ± 9 years. At baseline 1 patient had a > 30 mmHg LV gradient; during stress a LV gradient > 30 mm Hg developed in 6/21 patients (28%) and was caused by systolic anterior motion of the mitral valve in the 3 patients with severe gradient (mean 116 ± 29 mmHg), who developed mitral regurgitation and impaired apical wall motion and by obstruction at mid-ventricular level in the other 3 with a moderate gradient (mean 46 ± 16 mmHg). Compared with patients without obstruction those with obstruction had a greater mean septal thickness , a higher prevalence of septal hypertrophy  and a higher peak wall motion score index .Spontaneous or dobutamine-induced dynamic LV obstruction is documented in 32% of patients with LVBS, is correlated with the presence of septal hypertrophy and may play a role in the development of LVBS in this subset of patients. In those without septal hypertrophy a dynamic obstruction is rarely induced with dobutamine and is unlikely to be a major pathogenetic factor of the syndrome. Left ventricular ballooning syndrome (LVBS) is a recently described acute cardiac syndrome mimicking acute myocardial infarction, characterized by reversible regional apical or midventricular dysfunction whose pathogenetic mechanisms are as yet undefined -4. SympaThe study population was composed of 22 consecutive patients admitted with an acute coronary syndrome who fulfilled the diagnostic criteria for LVBS proposed by Mayo Clinic group  includinThe test was carried out at a mean of 9 ± 14 days from admission. Beta-blocking therapy was withdrawn 24 hours before the test. At baseline LV wall thickness and dimensions were measured by M-mode echocardiography in parastemal long axis view according to standard methods; a ≥ 12 mm end-diastolic wall thickness was considered indicative of wall hypertrophy. Dobutamine was administered at an initial dose of 5 mcg/kg/min for 5 minutes, with increase to 10 and 20, 30 and 40 mcg/kg/min for 5 minutes each under electrocardiographic and echocardiographic monitoring. The peak LV velocity was measured at rest, at the end of each stage and at peak stress by continuous wave Doppler from apical 4-or 5 chamber view. A pressure gradient >30 mmHg with a late peaking was considered significant for a dynamic intraventricular obstruction . A new oLeft ventriculography and multiplane coronary angiography were carried out according to standard methods. Ejection fraction was calculated by the area-length method. Coronary artery disease was defined as a ≥ 50% reduction in the luminal diameter of a major coronary artery. The TIMI flow grade classification and TIMI frame count were used to assess coronary blood flow in the 3 coronary arteries and calculated as previously described . A TIMI Data are presented as mean ± SD. Continuous variables were compared using a paired or unpaired Student's t test; categorical variables were compared by Fischer exact test.The main clinical findings of the patients studied are shown in table In basal conditions 5 patients showed a complete recovery of regional function while apical wall motion abnormalities were still present in 17. A localized proximal-mid septal hypertrophy was found in 6/22 patients (27%); no patient had a concentric LV hypertrophy. One patient showed a dynamic intraventricular gradient of 150 mmHg associated with systolic anterior motion of the mitral valve and mitral regurgitation and did not undergo DSE. In the remaining 21 patients heart rate increased from 67 ± 10 at baseline to 106 ± 18 beats/min at peak stress (p < .001) and systolic blood pressure increased from l30 ± 30 to 133 ± 27 mmHg (NS). Due to reduced diastolic filling time LV end-diastolic volume decreased from 99 ± 27 at baseline to 74 ± 30 ml at peak stress (p < .001) and end-systolic volume decreased from 48 ± 15 to 39 ± 23 ml (p < .002); mean walI motion score index improved from 1.4 ± .3 to 1.2 ± .4 (p < .01). A dynamic intraventricular gradient > 30 mmHg  with a late peaking developed in 6/21 patients (28%); the obstruction was localized in the outflow tract and caused by systolic anterior motion of the anterior mitral leaflet in 3 patients (mean gradient 116 ± 29 mmHg) (Figure Table Many pathophysiological mechanisms, including direct toxic effects of catecholamine overflow, epicardial coronary artery spasm and diffuse coronary microvascular dysfunction, have been hypothesized as possible causes of LVBS, but none of them has been convincingly demonstrated . The cloDobutamine stress echocardiography may be a useful tool for assessing the presence and significance of LV dynamic obstruction in patients with LVBS and for clinical decision making. However, the safety of the test in this setting has not been as yet assessed and further studies on a larger number of patients are warranted. Beta-blocking drugs decrease LV contractility and can prevent the development of dynamic intraventricular gradient and should therefore be the treatment of choice for patients with dobutamine-induced dynamic LV obstruction. The subgroup of patients who develop a severe outflow obstruction associated with major mitral regurgitation are at a higher risk of acute LV failure in the case of recurrences and should benefit from chronic beta-blocking therapy at maximal tolerated doses. and from intravenous beta-blockade if episodes of apical ballooning with dynamic obstruction recur.The authors declare that they have no competing interests.; AR performed the angiographic studies and reviewed the manuscript; SP collected the clinical data, performed the echocardiographic stress tests and reviewed the manuscript. All the authors have red and approved the final manuscript.MP planned the study, performed and interpreted the echocardiographic stress tests and wrote the manuscript; RC collected the clinical data, performed and interpreted the echocardiographic stress tests and reviewed the manuscriptExample of dobutamine-induced dynamic obstruction in one of the patient studied. Apical 4-chamber view in basal conditions showing no evidence of dynamic obstruction and mitral regurgitation and normal apical wall motion.Click here for fileApical 4-chamber view during dobutamine stress showing severe mitral regurgitation due to mitral SAM and impaired apical wall motion.Click here for file


We present the case of a woman born with transposition of the great arteries, who was surgically repaired with the Mustard technique. Because of interatrial shunting, she was brought to the cardiac catheterization laboratory for device closure. Matrix-array 3D transesophageal echocardiography enabled visualization of both baffle leaks and demonstrated its orientation in a fashion superior to 2D imaging, had it been used alone. The leaks were successfully closed with a single transcatheter device. Before the current era of the arterial switch operation, “atrial redirection” procedure for patients born with transposition of the great arteries (d-TGA) was commonly performed beginning in 1958 through the early 1990s. Two different atrial redirection operations — the Senning and Mustard procedures — had been developed to channel blood flow into the appropriate ventricles, allowing correction of the intense cyanosis that characterizes this condition. The two operations differ in the way the baffle is constructed, but residual or recurrent baffle leaks can occur with both procedures. Such leaks account for roughly 60% of the late reoperations.[2.One such patient at our institution was a 32-year-old woman born with d-TGA and pulmonary stenosis, who underwent the Mustard procedure at 1 year of age. She had reestablished care after a 4-year absence and was reportedly asymptomatic, although exercise testing suggested moderately diminished exercise capacity. Transthoracic echocardiography detected a 1 cm interatrial baffle leak with pulmonary venous to systemic venous shunting (“left to right” or “oxygenated to deoxygenated”). The pulmonary valve was dysplastic, with both stenosis and severe regurgitation; the peak velocity across the pulmonary valve being 3.6 m/s. By cardiac magnetic resonance imaging, her measured Qp:Qs was 1.5:1.0. The left (pulmonary) ventricle systolic function was normal but dilated, with an end diastolic volume of 118 ml/mBecause of the concern of the volume-loaded left ventricle from her pulmonary insufficiency and her atrial level shunt, she was referred for cardiac catheterization and transcatheter closure using transesophageal echocardiography (TEE) assistance. After initiating general anesthesia, a TEE probe with a matrix-array transducer and real-time three-dimensional imaging capability (3D TEE) was placed. Two separate defects were detected in the superior limb of the atrial baffle. The superior defect measured 9 × 10 mm and a smaller, more inferior defect measured 4 × 4 mm. The distance between the two defects was 9 mm and the entire area was well demonstrated by both 2D  and 3D TDuring TEE-assisted interventions, whether in the cardiac catheterization laboratory or in the operating room, the echocardiographer performing the TEE must acquire images using 2D sweeps, mentally reconstruct the anatomy and then verbally report the findings to the surgeon or interventional cardiologist. As an alternative, real-time 3-dimensional echocardiography (3DE), using a matrix-array transducer, can quickly create a simulated 3D picture. In addition to describing the anatomy, the imaging cardiologist can efficiently display the 3D images to the interventionalist or surgeon, possibly introducing additional clinical and diagnostic benefits.Other institutions have reported the successful use of 3D TEE during percutaneous interventions such as atrial septal defect closures3 and ele6


Screening for organ rejection is a critical component of care for patients who have undergone heart transplantation. Endomyocardial biopsy is the gold standard screening tool, but non-invasive alternatives are needed. Cardiovascular magnetic resonance (CMR) is well suited to provide an alternative to biopsy because of its ability to quantify ventricular function, morphology, and characterize myocardial tissue. CMR is not widely used to screen for heart transplant rejection, despite many trials supporting its use for this indication. This review summarizes the different CMR sequences that can detect heart transplant rejection as well as the strengths and weaknesses of their application.T2 quantification by spin echo techniques has been criticized for poor reproducibility, but multiple studies show its utility in screening for rejection. Human and animal data estimate that T2 quantification can diagnose rejection with sensitivities and specificities near 90%. There is also a suggestion that T2 quantification can predict rejection episodes in patients with normal endomyocardial biopsies.T1 quantification has also shown association with biopsy proven rejection in a small number of trials. T1 weighted gadolinium early enhancement appeared promising in animal data, but has had conflicting results in human trials. Late gadolinium enhancement in the diagnosis of rejection has not been evaluated.CMR derived measures of ventricular morphology and systolic function have insufficient sensitivity to diagnose mild to moderate rejection. CMR derived diastolic function can demonstrate abnormalities in allografts compared to native human hearts, but its ability to diagnose rejection has not yet been tested.There is promising animal data on the ability of iron oxide contrast agents to illustrate the changes in vascular permeability and macrophage accumulation seen in rejection. Despite good safety data, these contrast agents have not been tested in the human heart transplant population.T2 quantification has demonstrated the best correlation to biopsy proven heart transplant rejection. Further studies evaluating diastolic function, late gadolinium enhancement, and iron oxide contrast agents to diagnose rejection are needed. Future studies should focus on combining multiple CMR measures into a transplant rejection scoring system which would improve sensitivity and possibly reduce, if not eliminate, the need for endomyocardial biopsy. Heart transplantation is a life saving therapy for select individuals with end-stage heart failure. DespiteAcute cellular rejection is the most common form of heart transplant rejection. Cardiac transplant recipients have between one and three episodes of acute cellular rejection within the first year after transplantation . MoreoveSince the early 1970s the gold standard for detection of cellular cardiac rejection has been regular transjugular endomyocardial biopsy . MyocardIn the early stages of acute heart transplant rejection the myocardium is inflamed, however, there are often little or no symptoms, nor gross evidence of cardiac dysfunction ,12,13. SCardiovascular magnetic resonance (CMR) is the gold standard imaging modality for evaluation of ventricular volumes, morphology, and mass due to superior image quality as compared to echocardiography and nuclear modalities -23. CMR Since the late 1980s there have been many small trials  is influenced by myocardial water content and can clinically detect myocardial inflammation associated with myocarditis , Tako-TsT2 relaxation time is the decay time constant of magnetic signal after an excitatory pulse. T2 relaxation time is calculated by plotting the spin echo signal intensity against varying echo times and is believed to lengthen in proportion to the degree of myocardial edema Figure . Long T2Normal myocardial T2 relaxation times vary as a function of magnetic field strength and measured values will depend on whether or not an appropriate pulse sequence for quantifying T2 has been used. The last point cannot be stressed enough given that not all T2-weighted pulse sequences are appropriate for obtaining accurate T2 measurements. For this reason, CMR studies generally define their own normal T2 relaxation times from a group of controls and describe abnormal T2 relaxation as more than two standard deviations above the mean ,20,33.Since 1985, there have been eleven animal trials evaluating T2 relaxation time and transplant rejection. These trials have used predominantly rat and dog models and applied a variety of imaging platforms, transplant techniques and anti-rejection regimens. Nevertheless, they demonstrated that T2 relaxation times increased with histologic rejection ,30,40-45There have been eight human trials totaling 302 patients (521 CMR scans) comparing T2 relaxation times to transplant rejection as determined by endomyocardial biopsy  on ten healthy volunteers to establish normal values for T2 relaxation times and compared them with those obtained from 25 transplant patients scanned within 24 hours of endomyocardial biopsy . TransplIn a series of studies by Marie et al., it was found that T2 relaxation times were significantly higher in patients with International Society of Heart and Lung Transplant (ISHLT 1990) grade 2 or 3 rejection compared to those with less than grade 2 rejection  ,20. The Any assessment of diagnostic accuracy is predicated on the accuracy of the 'Gold Standard'. The utility of endomyocardial biopsy is clear, however, its diagnostic accuracy is not well characterized and is essentially impossible to study in a human population. The well recognized, and not uncommon, entity of biopsy negative rejection suggests that the sensitivity of endomyocardial biopsy is less than 100%. Therefore disagreements between CMR and biopsy may be a deficiency in CMR, endomyocardial biopsy or both. The subgroup analysis by Marie et al. that suggests that CMR might predict rejection in patients who are CMR 'positive' and biopsy negative raises the exciting possibility that CMR may be more sensitive than biopsy at detecting rejection.Signal dropout and motion artefacts are well recognized problems affecting image quality in T2 weighted spin-echo techniques. These pulse sequence deficiencies are accentuated by low magnetic field strength, arrhythmia, and long scan times. Most of the papers in the field of T2 imaging and transplant rejection predate the newer and shorter Turbo Spin Echo (TSE) sequences and relied on the much slower spin echo techniques with long scan times. In addition many studies presented in this review obtained their images using magnetic field strength well below the current standard of 1.5 T, which yields lower signal to noise ratios. Long scan times and low field strength could both have had significant negative impact on image quality. TSE sequences reduce scan times, but T2 quantification can be adversely affected by stimulated echoes. TSE sequences are also sensitive to RF and static field inhomogeneities . T2 weigHe et al. have recently developed a T2 quantification sequence for the purpose of measuring myocardial iron in patients with thalassemia . This noDespite the limitations of T2 weighted imaging mentioned above, previous work in transplant rejection studies has shown a consistent linear association between T2 relaxation times and the degree of acute transplant rejection. Furthermore, the relatively mild degree of rejection detectable with this technique (i.e. grade 2 ISHLT 1990) would not even require therapy in many contemporary transplant settings. This suggests that the relationship between T2 relaxation and rejection is highly sensitive and very unlikely to miss any cases of advanced rejection. Improvements in T2 imaging in the current era such as higher field strengths, fast TSE sequences, and improved blood and fat suppression techniques will likely strengthen the association between T2 relaxation times and transplant rejection.T1 weighted cardiovascular MR images are influenced by myocardial water content, although to a lesser extent than T2 weighted images. Non-contrast enhanced T1 signal intensity has shown an inconsistent correlation with rejection in animal models of heart transplantation ,45. NishThe T1 relaxation time can be calculated from a series of images acquired with an increasing delay following an inversion or saturation of the magnetization. A longer time of recovery is represented by larger T1 values, and like T2 values, this typically reflects an environment of fewer restrictions to water motion, such as edema. Aherne et al. and Nishimura et al. used a dog model to show that T1 relaxation times are prolonged in rejecting hearts compared to non-rejecting hearts ,45. AnimWisenberg et al. investigated 25 human heart transplant recipients and found that mean T1 relaxation times were significantly prolonged for those with rejection compared to non-rejectors  . In thisThe relationship between T1 relaxation and transplant rejection has been less well studied than that of T2 relaxation. The superior sensitivity to water content of T2 weighted imaging makes it a better choice for imaging myocardial inflammation, and likely accounts for the paucity of trials investigating T1 relaxation and rejection.Gadolinium based contrast agents are by far the most common contrast agents used in clinical CMR imaging. Intravenous gadolinium increases signal intensity on T1 weighted images acquired early after contrast administration, in proportion to the degree of tissue perfusion and is thought to reflect the hyperemia seen in inflamed tissue. Increase in signal intensity early after contrast injection (early enhancement) has shown utility in the diagnosis of other disorders of myocardial inflammation such as myocarditis . Abdel-AIn two human trials of transplant rejection, post contrast signal intensity tended to increase with degree of rejection although it could not consistently identify the full spectrum of abnormal endomyocardial biopsies diagnostic of rejection ,36. AlemThe correlation between biopsy proven rejection and echocardiographically determined ventricular morphology is specific in severe cases of acute cellular rejection but is too insensitive to be used as a screening tool . It has Myocardial wall thickness has been shown to increase in both animal ,61 and hRevel et al. studied 29 heart transplant patients using CMR and found that wall thickness increased during acute rejection and decreased as the rejection episode resolved . WisenbeChanges in ventricular morphology and systolic function as measured by CMR are associated with rejection ,63,64. DDiastolic dysfunction is one of the earliest measurable features of heart transplant rejection . YoshidaLeft ventricular twisting mechanics have also been studied in normal and transplanted hearts. Using magnetic resonance tagging, Donofrio et al. found that non-rejecting pediatric transplanted hearts had normal strain measurements, but abnormal torsion patterns compared to normal hearts. There wHansen et al. used implanted radio-opaque intramyocardial markers and biplane fluoroscopy to serially study twist and untwist in 12 heart transplant recipients . They foGadolinium can also be used in CMR to detect areas of myocardial scar or myocardial fibrosis. The rate at which gadolinium is cleared from the myocardium is slower in areas with fibrosis compared to healthy myocardium. T1 weighted images taken several minutes ("late") after contrast injection will show higher concentrations of gadolinium in areas of myocardial fibrosis making these areas appear bright. Late gadolinium enhancement (LGE) has correlated well to pathologic assessment of myocardial fibrosis in ischemic ,70 and nIron oxide contrast agents have been used in clinical and experimental MR since the 1980s predominantly in the field oncology -76. MoreKanno et al. showed that T2 signal intensity decreased 24 hours after iron oxide particle injection in untreated rat allografts compared to isografts at day seven (SI: 95% vs. 70%) . Signal Iron oxide contrast agents have also been used in a rat model of cardiac transplant rejection to study hyperemia. Immediately after injection, iron oxide particles remain intravascular unless there are alterations in local vascular permeability as seen in inflamed tissue. Extravasation of iron oxide particles leads to an increase in signal intensity in these regions on T1 weighted images. Johansson et al. showed that six days post transplant, T1 signal intensity was increased in untreated rat allografts compared to isografts within 5 minutes of iron oxide injection (mean difference 25%). Penno eCMR with iron oxide particles is a novel and potentially powerful method to evaluate inflammation in the heart. T1 Imaging early post iron oxide contrast injection can identify increased vascular permeability, while delayed T2 imaging gives information into in-vivo macrophage accumulation. Human trials of transplant rejection and iron oxide contrast agents are needed.Several CMR variables have shown good correlation to biopsy proven heart transplant rejection, the strongest of which is quantitative T2 assessment. Criticism regarding the reproducibility of T2 measures as well The authors declare that they have no competing interests.CB contributed to design of the review and manuscript preparation. RT contributed to design of the review and manuscript preparation. MH contributed to design of the review and manuscript preparation. MT contributed to manuscript preparation. IP contributed to design of the review and manuscript preparation.


The aim of this study was to evaluate the extent of epicardial adipose tissue (EAT) and its relationship with left ventricular (LV) parameters assessed by cardiovascular magnetic resonance (CMR) in patients with congestive heart failure (CHF) and healthy controls.EAT is the true visceral fat deposited around the heart which generates various bioactive molecules. Previous studies found that EAT is related to left ventricular mass (LVM) in healthy subjects. Further studies showed a constant EAT to myocardial mass ratio in normal, ischemic and hypertrophied hearts.CMR was performed in 66 patients with CHF due to ischemic cardiomyopathy (ICM), or dilated cardiomyopathy (DCM) and 32 healthy controls. Ventricular volumes, dimensions and LV function were assessed. The amount of EAT was determined volumetrically and expressed as mass indexed to body surface area. Additionally, the EAT/LVM and the EAT/left ventricular remodelling index (LVRI) ratios were calculated.2 versus 34 ± 4 g/m2, p < 0.0001). In the subgroup analysis there were no significant differences in indexed EAT mass between patients with ICM and DCM . Linear regression analysis showed that with increasing LV end-diastolic diameter (LV-EDD)  and LV end-diastolic mass (LV-EDM) , there was a significantly increased amount of EAT in patients with CHF. However, the ratio of EAT mass/LV-EDM was significantly reduced in patients with CHF compared to healthy controls . In CHF patients higher indexed EAT/LVRI-ratios in CHF patients correlated best with a reduced LV-EF .Patients with CHF had less indexed EAT mass than controls (22 ± 5 g/mPatients with CHF revealed significantly reduced amounts of EAT. An increase in LVM is significantly related to an increase in EAT in both patients with CHF and controls. However, different from previous reports the EAT/LVEDM-ratio in patients with CHF was significantly reduced compared to healthy controls. Furthermore, the LV function correlated best with the indexed EAT/LVRI ratio in CHF patients. Metabolic abnormalities and/or anatomic alterations due to disturbed cardiac function and geometry seem to play a key role and are a possible explanation for these findings. Human epicardial adipose tissue (EAT) is the true visceral fat of the heart whose regional distribution and function is of growing scientific and clinical interest. EAT covers 80% of the heart's surface and constitutes 20% of total heart weight. It is located in the atrioventricular and interventricular grooves, along the major branches of the coronary arteries, around the atria, over the free wall of the right ventricle and over the apex of the left ventricle . CardiaoAnatomically, there is a close relationship between the EAT and the muscular components of the heart. In a recent autopsy study, Corradi et al.  investigThus, the aim of this study was to assess the extent of EAT and its relationship to the LV ejection fraction (EF%), end-diastolic diameter (LV-EDD) and LV end-diastolic mass (LV-EDM) assessed by cardiovascular magnetic resonance (CMR) in patients with congestive heart failure (CHF) due to ischemic or dilated cardiomyopathy and healthy controls.A total of 66 patients  consecutive patients with a history of compensated symptomatic heart failure  and the presence of cardiac dysfunction on echocardiography study (left ventricular function ≤ 35%) for more than one year were included in the study. For the traditional binary classification (ischemic vs. nonischemic), an ischemic aetiology of heart failure was defined as the presence of any epicardial coronary vessels with ≥75% stenosis or any history of myocardial infarction or coronary revascularization. The number-of-diseased-vessels classification was defined as the number of vessels with ≥75% stenosis . The diagnosis of dilated cardiomyopathy was based on M-mode and 2D/Doppler echocardiographic examination demonstrating an end-diastolic diameter >56 mm and a normal coronary angiography performed within the previous 6 months.The 32 healthy volunteers  satisfied the following criteria: normal physical examination, normal blood pressure (< 120 mm Hg and <80 mm Hg), normal ECG findings, no history of chest pain or dyspnea, no diabetes, and normal 2D echocardiographic and Doppler examination. None of the subjects was on medication. Any potential subjects with evidence of heart disease, hypertension or other systemic disorders were excluded from the study.All studies were performed using a 1.5 Tesla whole-body imaging system . A dedicated 4-element, phased-array cardiac coil was used. Images were acquired during repeated end-expiratory breath-holds. Scout images  were obtained for planning of the final double-oblique long-axis and short-axis views. To evaluate functional parameters, electrocardiogram-gated cine images were then acquired using a segmented steady-state free precession [fast imaging with steady-state precession (true-FISP)] sequence . Seven to 12 short-axis views covering the whole left and right ventricle were obtained. For the assessment of the epicardial adipose tissue, we used a dark blood prepared T1-weighted multislice turbo spin-echo pulse sequence with a water suppression prepulse to obtain a transversal 4-chamber view and short-axis images in the same orientations used for the cine short-axis images. Imaging parameters were as follows: time of repetition = 800 ms, time to echo = 24 ms, slice thickness = 4 mm, interslice gap = 2 mm, and field of view = 30 to 34 cm.Ten minutes after injection of a gadolinium-based contrast agent , a segmented inversion recovery cine trueFISP pulse sequence (TI scout) acquisition was performed at a midventricular short-axis location. This acquisition was used to determine the TI at which the signal of normal myocardium is null for the subsequent late gadolinium enhancement (LGE) acquisition. After that, LGE images were acquired in the same orientation as the cine images using a 2D-segmented inversion recovery gradient-echo pulse sequence triggered to end-diastole . LGE was only considered to be present if it was also present in the same slice after swapping phase encoding, thus excluding artifacts.Image analysis and quantitative analysis was performed off-line using dedicated software . Each study was examined for abnormalities in the morphology of the right and left ventricle. End-diastolic and end-systolic volumes and left ventricular mass was analyzed with the serial short-axis true-FISP cine loops, using manual segmentation. Stroke volumes and ejection fractions were calculated. Additionally, left- and right-ventricular diameters were measured.3). The observer was blinded to patient details.The amount of EAT was calculated by using the modified Simpson's rule with integration over the image slices. The contours of EAT were outlined at end diastole in the short-axis views covering the entire left and right ventricle. For EAT mass determination, the area subtended by the manual tracings was determined in each slice and multiplied by the slice thickness to yield the fat volume. Total EAT volume was obtained after the data summation of all slices. To obtain EAT mass, the volume of EAT was multiplied by the specific weight of fat  was calculated as the ratio of left ventricular mass (LV-EDM) to left ventricular volume (LV-EDV) as previously published by De Castro S et al.  who estaTo assess inter- and intraobserver reproducibility of the volumetric EAT measurements, two blinded investigators evaluated 40 randomly selected subjects among the study population and one of them repeated the measurements two weeks after the first evaluation.LGE was assessed visually, and the LGE mass was measured by manual planimetry on all short-axis slices by an observer blinded to all patient details. Summing the LGE mass of all slices yielded the total mass of LGE. The extent of LGE was then expressed as a percentage of the total LV mass.2) = weight (kg)/height (m)2. Body surface area (BSA) was assessed by a variation of the DuBois and DuBois formula: BSA (m2) = [weight (kg)0.425 × height (cm)0.725] × 0.007184 [2 test was applied for nonparametric data. A p-value <0.05 was considered significant for all comparisons. Linear regression analysis was performed on anthropometric and CMR parameters to identify correlates of EAT. Multivariate analysis was performed with logistic regression analysis using block entry of the following variables: LV-EF (%), RV-EF(%), LV-EDD (mm) and indexed LV-EDM (g/m2) to evaluate if these variables were independent predictors of indexed EAT mass. Besides, univariate linear regression analysis was performed between LV-EF and indexed EAT in CHF patients and healthy controls separately. Furthermore, univariate linear regression analysis was applied to determine the correlation between LV-EF and left ventricular remodelling index (LVRI) calculated as the ratio of left ventricular mass (LV-EDM) to left ventricular volume (LV-EDV) as well as the indexed EAT/LVRI-ratio in patients with CHF. Additionally, the LV-EDM and the indexed EAT was compared in CHF patients with and without hypertensive heart disease. Analysis was performed using SPSS statistical software .The data are presented as mean value SD. Body mass index (BMI) was calculated by the common formula: BMI  between the indexed EAT of healthy controls and CHF patients derived from the results of our previous study [The inter- and intraobserver reproducibility was assessed by Bland-Altman analysis, providing the mean difference (d) and its limits of agreement .The baseline characteristics of all subjects studied are shown in Table Comparing the baseline characteristics of patients with ICM and DCM Table  it becomIn our study cohort 21/66 (31.8%) patients suffered from diabetes mellitus and were treated with oral antidiabetic medication 15/66 (22.7%) or insulin 6/66 (9.1%). 17/66 (36%) suffered from hypertensive heart disease. Hyperlipidemia was diagnosed in 38/66 (57.6%). 24/66 (36.4%) were smoker and 15/66 (22.7%) had a family history of CAD.Among the patients with ICM 34/36 (94%) suffered an acute myocardial infarction 11.6 ± 7.3 years ago. None of the DCM patients had a history of prior myocardial infarction.The severity of symptoms at admission was assessed by NYHA classification. None of the patients were in NYHA class I, 7/66 (11%) patients in II, and 59/66 (89%) patients in III-IV.The CMR characteristics of our study cohort are summarized in Table In patients with CHF, left ventricular ejection fraction (LV-EF) and right ventricular ejection fraction (RV-EF) were significantly reduced whereas left ventricular end-diastolic diameter (LV-EDD) and right ventricular end-diastolic diameter (RV-EDD) as well as indexed left ventricular end-diastolic mass (LV-EDM) were significantly elevated compared to controls. Indexed EAT mass in patients with heart failure was significantly lower compared to controls as illustrated in Figure The intra- and interobserver correlation of EAT determination was good. The corresponding Bland-Altmann plots for the intraobserver and interobserver variability showed a mean value of 0.69% vs 3.18%, a SD of ± 0.96% vs ± 3.13% and limits of agreement from -1.1% to +2.5% vs -3.0% to +9.3% (intraobserver vs interobserver variability respectively).In patients with CHF simple linear regression analysis revealed a significant correlation of indexed EAT mass with LV-EF , LV-EDD , indexed LV-EDM  and RV-EF . This correlation was also existent in subgroup analysis in patients with DCM and ICM. In patients with ICM there was no significant correlation between indexed EAT and the LGE extent (%) . No correlation was found between indexed EAT mass and RV-EDD  as well as the anthropometric parameters age  and BMI . In healthy controls indexed EAT mass only correlated with indexed LV-EDM . Multivariate logistic regression analysis, a model using the LV-EF, LV-EDD, indexed LV-EDM and RV-EF to predict the extent of EAT in patients with CHF, showed that indexed LV-EDM was the only parameter that was independently associated with the indexed EAT mass (p = 0.0001).2 versus 22.2 ± 4.8 g/m2, p = 0.87) results between CHF patients with and without hypertensive heart disease there was no significant difference.As illustrated on Figure In CHF patients a reduced LV-EF correlated inversely with the LGE extent % . Looking at the correlation between LV-EF and indexed EAT as well as parameters of left ventricular remodelling, there was no significant correlation between LV-EF and indexed EAT in healthy controls , EAT is significantly reduced compared to healthy controls. The reduction of EAT is irrespective of the underlying aetiology of the cardiomyopathy. Like in healthy controls an increase in left ventricular mass also leads to an augmentation of the EAT mass in patients with CHF, however, the EAT mass/LV-EDM ratio is significantly lower compared to healthy controls.The amount of EAT has been assessed by numerous imaging modalities ,4,9,10. So far, the role of EAT and its contribution to the development of cardiac pathology is quite ambiguous. There is growing evidence of a close functional and anatomical relationship between the adipose tissue and muscular components of the heart. Its close proximity to the myocardium suggests that EAT as a metabolically active organ and a source of several bioactive molecules may influence cardiac morphology and function ,11,12. UOur results showed that patients with CHF had less indexed EAT mass than controls. In the subgroup analysis there were no significant differences in indexed EAT mass between patients with ICM and DCM. In healthy controls there was no significant correlation between indexed EAT and LV-EF. In contrast, CHF patients revealed a significant inversed correlation between indexed EAT and LV-EF as well as RV-EF and a linear correlation between indexed EAT and LV-EDD. However, indexed EAT did not correlate with RV-EDD, which was due to the predominantly left ventricular heart failure. Compared to healthy controls who possessed a normal left ventricular remodelling index (LVRI), CHF patients had a significantly reduced LVRI. In CHF patients, the reduced LV-EF showed a positive correlation with the decreased LVRI. As indicated by a significant interaction between indexed EAT and left ventricular remodelling, higher indexed EAT/LVRI-ratios in CHF patients correlated best with a reduced LV-EF. This correlation existed regardless of the underlying aetiology of heart failure. The reversal of the correlation between LV-EF and indexed EAT seen in our CHF patients can be explained by the modification in left ventricular shape and size coming along with left ventricular remodelling due to progressive heart failure. Since changes in left ventricular geometry are dynamic, affecting both mass and volume, the LVRI is significantly reduced in CHF patients. With decreasing LV-EF, CHF patients showed an decrease in LVRI and indexed EAT increase resulting in an increasing indexed-EAT-LVRI ratio, indicating a remodelling not compensated by an adequate EAT increase.The extent of LGE in our 36 ICM patients was 32.6 ± 10.4%. As anticipated there was a significant correlation between the LV-EF and the LGE extent, whereas no significant correlation existed between indexed EAT and the LGE extent. However, due to the small number of patients in the subgroup analysis, our study might be underpowered for this analysis.Previous studies ,17 showeIn patients with CHF and a severely reduced LV-EF, the reduced EATmass/left ventricular mass ratio may indicate a decreased buffering capacity for excess fatty free acids as well as a diminished responsiveness to adjust to special energy demands of the heart. A reduction of EAT may result in a reduced adiponectin production that has shown to exert protective effects under ischemic conditions .One limitation of our study is the relatively small number of study participants. Larger randomized trials including patients with various degrees of left ventricular function impairment are needed to generalize our observations and to prove whether they are linearly related to LV-EF decrease.Due to the different disease course and time of manifestation patients with dilated cardiomyopathy were younger than those with ischemic cardiomyopathy. However, as the thickness of EAT does not change between the age of 40 and death  this facWe found a correlation between EAT and several MRI parameters indicating left ventricular remodeling. However, as correlation is a necessary but not a sufficient condition to make causal inference with reasonable confidence, our study was not targeted on causal relationships among these parameters and EAT and no conclusion on the causality of the parameters can be drawn. It will be the challenge of further studies to evaluate the potential causal explanations of the observed correlations.Patients with CHF revealed significantly reduced amounts of EAT compared to healthy controls irrespective of the underlying aetiology of the cardiomyopathy. An increase in LVM is significantly related to an increase in EAT in both patients with CHF and controls. However, different from previous reports the EAT/LVEDM-ratio in patients with CHF was significantly reduced compared to healthy controls. Metabolic abnormalities and/or anatomic alterations due to disturbed cardiac function and geometry seem to play a key role and are a possible explanation for these findings. Furthermore, as indicated by a significant interaction between indexed EAT and left ventricular remodelling, higher indexed EAT/LVRI-ratios in CHF patients correlated best with a reduced LV-EF.CHF: congestive heart failure; CMR: cardiovascular magnetic resonance; DCM: dilated cardiomyopathy; EAT: epicardial adipose tissue; ICM: ischemic cardiomyopathy; LA: left atrium; LGE: late gadolinium enhancement; LV: left ventricle.The authors declare that they have no competing interests.CD evaluated CMR images, participated in study-design, performed statistical analysis and drafted the manuscript, figures and tables. DH contributed equally to the writing of this manuscript. SF participated in study-design and evaluation of CMR data. TS participated in study-design and the revision of the manuscript. SS participated in study-design and evaluation of CMR-images. HM participated in the revision of the manuscript and repeated the EAT volumetry to assess interobserver measurement reproducibility. MB participated in study-design, scientific and clinical advice concerning CHF and was responsible for the revision of the manuscript. TP participated in study-design and its coordination, performed and evaluated CMR images and was responsible for the revision of the manuscript. All authors read and approved the final manuscript.


R = 4.A single breath-hold evaluation of ventricular function would allow assessment in cases where scan time or patient tolerance is limited. Spatiotemporal acceleration techniques such as TSENSE decrease cardiovascular MR acquisition time, but standard slice summation analysis requires enough short axis slices to cover the left ventricle (LV). By reducing the number of short axis slices, incorporating long axis slices, and applying a 3D model based analysis, it may be possible to obtain accurate LV mass and volumes. We evaluated LV volume, mass and ejection fraction at 3.0T using a 3D modeling analysis in 9 patients with a history of myocardial infarction and one healthy volunteer. Acquisition consisted of a standard short axis SSFP stack and a 15 heart-beat single breath-hold six slice multi-planar (4 short and 2 long axis) TSENSE SSFP protocol with an acceleration factor of Differences (standard minus accelerated protocol mean ± s.d.) and coefficients of variation (s.d. of differences as a percentage of the average estimate) were 7.5 ± 9.6 mL and 6% for end-diastolic volume (p = 0.035), 0.4 ± 5.1 mL and 7% for end-systolic volume (p = NS), 7.1 ± 8.1 mL and 9% for stroke volume (p = 0.022), 2.2 ± 2.8% and 5% for ejection fraction (p = 0.035), and -7.1 ± 6.2 g and 4% for LV mass (p = 0.005), respectively. Intra- and inter-observer errors were similar for both protocols .These results suggest that clinically useful estimates of LV function can be obtained in a TSENSE accelerated single breath-hold reduced slice acquisition at 3T using 3D modeling analysis techniques. Although Cardiovascular Magnetic Resonance (CMR) imaging provides accurate assessment of left ventricular (LV) mass and volumes , the datEvaluation of ventricular function from a single breath-hold acquisition would be advantageous in cases where scan time is at a premium, for example where patient tolerance is poor, or where ventricular function is not the primary clinical goal but a rapid estimate of ventricular function would add clinical value. Also, rapid evaluation of ventricular function is required where transient effects are being studied, for example under pharmacological or exercise stress conditions, or in transient alterations to pre- or after-load conditions. Furthermore, single breath-hold acquisitions avoid errors due to variability in diaphragmatic position, and therefore cardiac position, between successive breath-holds.et al. [Fast imaging techniques have been proposed to reduce the acquisition time, enabling multi-slice acquisitions within a breath-hold by utilizing parallel  and realet al.  showed tThis study sought to evaluate left ventricular volumetric parameters 3.0T, using 3D guide-point modeling analysis  and singTen individuals , comprising nine patients and one healthy volunteer, were enrolled in the study. All patients had history of myocardial infarction with documented regional wall motion abnormality  and/or impaired systolic global LV function. Written informed consent was obtained from all subjects and the appropriate regulatory authorities approved the study protocol. Comparisons of accelerated and non-accelerated acquisitions using slice summation analyses in this group have been reported previously [R = 4 was then performed, obtaining six slices  within a single breath-hold. The short axis slices were planned according to the AHA segmental model – basal, midventricular and apical, with an additional slice through the apex [Subjects were imaged on a 3.0T whole body scanner . A segmented SSFP scout sequence simulating varying frequency offsets (-200 to 200 Hz) to the adjusted resonance frequency was used along a cardiac four chamber view and the shift with least image artifacts was implemented for all subsequent CINE SSFP data acquisitions . Standarthe apex . As far All 20 studies were assigned a random number and then analyzed by a single observer (four years experience) in random order blinded to patient identifier, using guide-point modeling . The analyst could not be blinded to the acquisition method, due to the different number of slices in each method. Based on the study analyses, left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and myocardial mass were calculated by numerical integration of the model surfaces. LV mass was calculated for every phase and then averaged . In order to determine intra-observer reproducibility, all studies were randomized a second time and re-analyzed by the same observer, blinded to previous results. Accuracy (relative to the non-accelerated acquisition) and reproducibility (intra-observer errors) were quantified for LV mass, EDV, ESV, SV and EF. A second blinded observer also analyzed all studies in order to estimate the inter-observer variability.Repeated measures ANOVA was performed using both analyses of both acquisitions. Fixed effects in the ANOVA model were repeated analyses, acquisition protocol (i.e. "standard" acquisition versus "accelerated" single breath-hold acquisition), and their interaction. A significant interaction between repeated analysis and acquisition protocol would indicate that the reproducibility of the estimate was dependent on the acquisition method. If significant effects were found, Scheffé post-hoc tests were performed to test for significant differences between each of the acquisition protocols and repeated analyses. Significance was defined as p < 0.05.Figure For EDV, the only significant effect on ANOVA was acquisition protocol . On post-hoc tests this difference was significant in both analyses (Scheffé p < 0.01 for both). For ESV, no overall effects were significant on ANOVA. For SV, the only significant effect was acquisition protocol . On post-hoc tests this difference was significant in both analyses (Scheffé p < 0.05 for both). For EF, the only significant overall effect was acquisition protocol . However, on post-hoc tests this difference was not significant in each analysis (Scheffé p = NS for both). For LVM, significant effects were found due to repeated analysis  and acquisition protocol . However, on post-hoc tests, no differences were significant between analyses in each acquisition protocol, or acquisition protocols in each analysis .For all functional parameters, the interaction between repeated analysis and acquisition protocol was not significant, indicating that intra-observer error was similar in both the standard and accelerated protocols.Inter-observer errors are shown in Table Although current acquisition protocols enable accurate estimation of LV function, the time requirements of these protocols are relatively large. Due to practical constraints such as patient tolerance, available scan time and patient comfort, more rapid evaluation of ventricular function is desirable. Rapid acquisition of ventricular function would also facilitate investigation of transient phenomena including pharmacological or exercise stress studies, and preload and afterload manipulations, for example during performance of the Valsalva maneuver. In order to achieve faster image acquisition, compromises may need to be made in the areas of LV coverage, spatial and temporal resolution, and SNR. In the present study, the first compromise was ameliorated by 3D modeling, the second by TSENSE and the third by higher field strength (3T).Single breath-hold acquisition for LV function has been previously evaluated using a real-time SSFP protocol . In ordeR = 2. Comparison with a standard SSFP protocol showed differences of 4 ± 12 mL for EDV, 1 ± 5 mL for ESV, 3 ± 10 mL for SV, 0 ± 2% for EF in 18 patients. These results are comparable with the present study; however the present protocol had a shorter breath-hold duration and higher spatial resolution.Parallel imaging methods were used in  to improR = 3 allowed a 14 short axis slice 3D acquisition (with 2 slices discarded) in 18–20 beats, ~2.5 mm/pixel spatial resolution and ~50 ms reconstructed temporal resolution. The mean differences were 3 ± 15 mL in EDV, 1 ± 11 mL in ESV, 1 ± 4% in EF, and 1 ± 11 g in LV mass in 15 patients and 22 volunteers. These results correspond to higher coefficients of variation than the present study.Parallel imaging has also been exploited in 3D SSFP techniques to achieve single breath-hold acquisition of LV function. In , SENSE 3Single breath-hold 4D kt-BLAST accelerated techniques have been recently investigated for ventricular function ,15. In , a 12–14et al. [Fieno et al.  applied Guide point modeling has been proposed as an accurate and efficient tool for LV volumetric analysis . The metThe results of the present study showed that EDV was underestimated by 5% in the accelerated acquisitions, leading to underestimations in SV 8%) and EF (4%). Interestingly, the estimate of ESV was not significantly different between accelerated and standard acquisitions. This is in accordance with a previous investigation in the same subjects % and EF .LV mass was overestimated by 5% within the accelerated protocol, and reproducibility was worse for LV mass than all other volumetric parameters. One possible cause for the increased variability in LV mass may be decreased myocardial signal due to reduced flip angle to comply with SAR constraints, leading to increased uncertainty in the location of the epicardial contour relative to the low signal in the lungs. The Bland Altman plot for LV mass shows a tendency for increased difference with larger mass, possibly due to the reduced SNR in the TSENSE acquisition, as the maximum error of 8% may be attributed to a displacement of the epicardial contour of less than half a pixel.The application of the reduced slice protocol is intended only for cases in which a full slice protocol is not possible or desired. The reduced slice protocol is not appropriate for applications such as research trials with cardiac mass and volume endpoints in which inter-study variability is very important. The reduced slice protocol is unlikely, on its own, to be as effective as a full stack of short axis cines for the assessment of regional wall motion abnormalities or, when supplemented by late gadolinium enhancement imaging, for viability assessment. A reduced slice accelerated acquisition protocol could also be applied to the right ventricle, and geometric models of right ventricular shape and motion are being constructed. However, the complex geometry of the right ventricle, with separated inflow and outflow tracts, may result in decreased accuracy using a reduced slice protocol. In this case it might be advantageous to trade some of the short axis slices for more long axis slices, for example in the inflow and outflow tracts.A limitation of the current study was the small number of patients scanned. This study was performed mainly in patients with a history of myocardial infarction, since it was expected that regional abnormalities in LV shape and motion typically observed in such patients could lead to decreased accuracy when assessed with a reduced slice acquisition protocol. Also, the myocardial signal intensity may have been compromised by the need to comply with SAR constraints and accelerate the acquisition. Future improvements in SNR with higher acceleration factors may be achieved with a higher density of receive coils , which mSingle breath-hold ventricular function evaluation involves a trade-off in spatial resolution, temporal resolution, and SNR. In this study TSENSE accelerated multi-planar segmented cine acquisition enabled high spatial and temporal resolution while reduced ventricular coverage was compensated by 3D modeling, and SNR improved by higher field strength. These preliminary data demonstrate the feasibility of single breath-hold LV assessment at high spatial and temporal resolution with acceptable reproducibility at 3.0T.Six slice TSENSE single breath-hold acquisition with LV model. A typical result of the beating LV model customized to six slices acquired in a single breath-hold TSENSE acquisition. The four chamber long axis SSFP image is shown with the LV model endocardial surface shaded in red. The blue lines are the intersections of the LV epicardial surface with the image planes. Note apical and basal motions are well characterized by the long axis slices.Click here for file


After a transient ischemic episode, the subendocardial region is more severely injured than outer subepicardial layers and may regain a proportionately greater degree of mechanical function in the longitudinal direction. We sought to explore left ventricular (LV) transmural mechanics in patients with ST-segment elevation myocardial infarction (STEMI) for determining the mechanism underlying recovery of global LV function after primary percutaneous coronary intervention (PCI).A total of 42 patients  with a first STEMI underwent serial assessments of LV longitudinal, circumferential and radial strains  by selective tracking of subendocardial and subepicardial regions within 48 hours and a median of 5 months after PCI. LV mechanical parameters were compared with sixteen age and gender matched normal controls.In comparison with controls, endocardial and epicardial LS were markedly attenuated at 48 hours following PCI (P < 0.001). An improvement in LV ejection fraction (EF > 5%) following PCI was seen in 24 (57%) patients and was associated with improvement in endocardial and epicardial LS  and endocardial CS (P = 0.01). Radial strain and wall motion score index, however, remained persistently abnormal. The change in endocardial LS  and the change in epicardial LS  were significantly associated with the improvement in LVEF, independent of the location of STEMI and the presence of underlying multivessel disease.In patients with STEMI treated by PCI, the recovery of LV subendocardial shortening strain seen in the longitudinal direction underlies the improvement in LV global function despite persistent abnormalities in radial mechanics and wall motion score index. Left ventricular (LV) structure and function exhibits substantial transmural heterogeneity. Myofiber orientation changes gradually from a right-handed helix in the subendocardium to a left-handed helix in the subepicardium . BesidesContractile dysfunction after ischemia and reperfusion in vitro is associated with a significant transmural gradient of dysfunction between epicardial and endocardial layers . The serIn this investigation we explored the longitudinal, circumferential and radial mechanics of the LV in patients with ST-segment elevation myocardial infarction (STEMI) for determining the selective contribution of subendocardial and subepicardial region to the recovery of global LV function after primary percutaneous coronary intervention (PCI). We hypothesized that there is preferential recovery of subendocardial longitudinal shortening in STEMI after primary percutaneous coronary intervention (PCI).The Mayo Clinic Institutional Review Board approved the study. We retrospectively studied and enrolled 42 patients  with their first STEMI referred to the catheterization laboratory at our institution for emergency PCI between January 1, 2005 and December 31, 2008. Patients presenting within six hours of the onset of symptoms suggesting an acute myocardial infarction, associated with ≥ 0.2 mV (2 mm) ST elevation in ≥ 2 contiguous anterior leads or limb leads with a summed ST elevation ≥ 1.0 mV (10 mm) in all leads on the presenting electrocardiogram, and in whom primary PCI was planned, were eligible for this study. The exclusion criteria were fibrinolytic therapy, previous infarct history, atrial fibrillation, significant valvular heart disease, life-limiting non-cardiac disease, previous history of chronic congestive heart failure. Serial clinical data including demographics, co-morbid conditions, and laboratory results were recorded for each individual. All patients underwent a comprehensive echocardiographic examination within 48 hours and during follow up (median 5 months) after the primary PCI. LV mechanical parameters were compared with 16 subjects served as controls with similar age and gender to the study population  with normal echocardiograms. Control group risk factors included hypertension in 6, dyslipidemia in 5, diabetes in 1 and family history of cardiovascular diseases in 2, but none had coronary artery disease or known structural heart disease.Echocardiographic studies were performed on commercially available ultrasound equipment  according to the standard method recommended by the American Society of Echocardiography. The LV volumes and ejection fraction (EF) were obtained by the modified biplane Simpson's method from the apical 4- and 2-chamber views. The LV wall was divided into 16 segments and the wall motion of each segment was visually evaluated and scored with the following scale: 1 = normal; 2 = hypokinesis; 3 = akinesis; 4 = dyskinesis; and 5 = aneurysmal. The average of the score of evaluated segments served as the WMSI. The mitral early diastolic flow (E) velocity and late diastolic flow (A) velocity were measured and the E/A ratio calculated. The deceleration time of the mitral E wave was also measured and Doppler tissue imaging was obtained from the apical four-chamber view. The digital images were obtained at optimal frame rates (≥ 30 frames per second). Images were stored in digital cineloop format  for offline analysis by vendor customized 2-D Cardiac Performance Analysis software . 2D CPA is a speckle tracking based analysis tool that can analyze 2D data from various ultrasound machines and is an extension of velocity vector imaging software that has been previously validated with sonomicrometry ,9 and maAll continuous data were reported as mean ± SD, and categorical data, as percentage. Chi-square and the unpaired Student t test were used for comparisons between two groups for categorical and continuous variables, respectively. A P value less than 0.05 was considered statistically significant. Pearson's correlation coefficient was used to reveal relations between two continuous variables. Univariate logistic regression analysis was used to compare clinical and echocardiographic variables with improvement in LVEF during follow up using commercially available software . Inter- and intra-observer variability was calculated as the absolute difference of the corresponding pair of repeated measurements in percent of their mean in each patient and then averaged for 18 randomly selected patients. To evaluate intra observer agreement among two readers of WMSI, the mean kappa and its 95% confidence interval was calculated. The kappa coefficient of agreement was graded as follows: 0 to 0.2 = poor to slight; 0.21 to 0.4 = fair; 0.41 to 0.6 = moderate; 0.61 to 0.8 = substantial; and 0.81 to 1.0 = nearly perfect.The clinical characteristics of STEMI patients with and without improvement in LVEF at baseline are summarized in Table Table In comparison to controls, global endocardial and epicardial longitudinal strains were markedly attenuated at 48 hours following PCI . There was an improvement during follow up in 24 (57%) patients . Similarly, endocardial circumferential strain was improved at serial follow up , however radial strains and WMSI remained persistently abnormal  and the change in epicardial longitudinal strain  were significantly associated with the improvement in LVEF, independent of the location of STEMI and the presence of underlying multivessel disease  often accompanied by a decline in left ventricular (LV) ejection fraction (EF). The decline in LVEF is believed to be due in part to loss of initially contracting myocardium and chamber enlargement from progressive post infarction dilatation, resulting in a rise in end systolic volume ,14. A nuOne explanation for the lack of radial component improvement observed in this study and the limitation of WMSI in characterizing functional improvements following AMI is that LV wall thickening is not a result of simple shortening of individual myocytes but rather an effect of groups of myocytes shearing across one another. Transmural shearing results from sliding and rearrangement of myofiber sheets along cleavage planes during the cardiac cycle -4. FolloImportantly, there was a trend towards higher prevalence of pre-existing hypertension, hyperlipidemia and diabetes in the group without improvement of global LV function as determined by LV ejection fraction, although the difference did not meet statistical significance. This is not surprising given that both diabetes and hypertension are independent predictors of mortality after STEMI that are incorporated into the TIMI risk score . The durEchocardiography has several well-established uses in the setting of AMI including the determination of location and extent of ischemia or infarction, detection of complications, and risk stratification of individuals . The walMore recently, because of their unique ability to detect layer-specific changes in mechanical function, markers of tissue deformation (strain and strain rate) measured by tissue Doppler or speckle tracking are now actively being studied for their potential use as prognostic tools after AMI . Global The present study represents a relatively small number of STEMI patients who received PCI at our institution and had 2-D echocardiography and speckle tracking analysis performed within 48 hours of MI and on average 6 months afterwards. There was variability in the timing of follow-up echocardiography; however the majority of subjects (41 of 42) had follow-up > 2 months after STEMI. The purpose of the study was to do a head to head analysis of WMSI and LV mechanics both of which were performed at the same time point for every subject. Long term clinical outcomes including subsequent major adverse cardiac events and mortality were not measured and will be important to examine for future speckle tracking imaging investigations in this population.Abnormal longitudinal and circumferential strain is frequently present after AMI and improves to a greater degree than abnormal systolic wall motion abnormality in patients with STEMI treated by PCI. Improvement in global LV function in STEMI patients treated with PCI occurs primarily by augmentation of LV longitudinal and circumferential shortening mechanics. Left ventricular radial mechanics remain persistently abnormal and may explain the limited ability of WMSI in characterizing functional improvements following PCI.AMI: acute myocardial infarction; EF: ejection fraction; LV: left ventricular; MRI: magnetic resonance imaging; PCI: percutaneous coronary intervention; STEMI: ST-elevation myocardial infarction; WMSI: wall motion scoring index.The authors declare that they have no competing interests.GC and HA carried out LV mechanics analysis, collected data, performed statistical analysis and drafted the manuscript. ME contributed to analysis and interpretation of data and drafting of the manuscript. NB collected data and contributed to study design. SW, SC and FD contributed to the analysis of echocardiography and cardiac catheterization data. PS was responsible for study design, analysis and interpretation of data, manuscript drafting and critical revision. All authors read and approved the final manuscript.GC is enrolled in PhD program at: University of Messina, Piazza Pugliatti, 1, 98122 Messina, Italy. All authors are affiliated with: Division of Cardiovascular Diseases, Mayo Clinic College of Medicine, Arizona, USA.


We present an unusual case of cardiomyopathy in a two month old male infant with a grade-I systolic murmur. Echocardiographic examination disclosed left ventricular (LV), dysplasia with saw-tooth like inwards myocardial projections extending from the lateral walls towards the LV cavity. There was mild LV systolic dysfunction with apical hypokinesia. Cardiovascular magnetic resonance demonstrated in detail these cross bridging muscular projections originating from the inferior interventricular septum and lateral LV wall, along with areas of hypokinesis at the LV septum and apex in a noncoronary distribution, without any late gadolinium enhancement. We have termed this condition saw-tooth cardiomyopathy because of the very characteristic appearance. A two month old asymptomatic male infant was referred to our Congenital Heart Disease Program for assessment of a grade-I systolic murmur discovered during a routine paediatric examination. The mother reported an uncomplicated pregnancy, without any family history of heart disease. There was no history of medication or illegal drug use during pregnancy. Labor was also uncomplicated with an APGAR score of 10. The infant was generally well, with no other clinical signs of heart disease. The electrocardiogram was normal. Brain Natriuretic Peptide (BNP), levels were 352 pg/ml [The incidence of heart muscle disease induced new-onset heart failure in the absence of congenital heart disease in children, has been recently reported in a nationwide multicenter study from UK and Ireland to be 87 per 100,000 population less than 16 years. The medWe present a form of LV dysplasia of the newborn with unique morphologic features, which we have termed saw-tooth cardiomyopathy because of the very characteristic appearance.Written informed consent was obtained from the mother of the infant 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.PDavlouros, AK and MK performed independent echocardiograms, interpreted and edited the images and discussed the differential diagnosis of this rare case. PDanias performed the CMR study and interpreted the corresponding images. PDavlouros and PDanias drafted the manuscript. DA helped to write and rewrote the manuscript.