Iranian Heart Journal
Volume:11 Issue: 3, Fall 2010

Background Hypertrophic cardiomyopathy (HCM) is a genetic cardiovascular disease with tremendous heterogeneity in its phenotypic expression. Global systolic function measured by ejection fraction (EF) does not seem to be a reliable marker for myocardial contractility in these patients. Tissue Doppler Imaging (TDI) indices, strain, and strain rate (SR) may be helpful in discriminating HCM from other mimetics. We decided to measure the regional myocardial function by strain and SR imaging to determine whether the regional myocardial function is related to the global systolic function and whether systolic strain and SR are reduced in all types of HCM. Method Forty-one consecutive patients (20 women, mean age ± SD = 41 ± 13.0 years) with HCM were included. All the patients underwent complete clinical and echocardiographic evaluations. The global systolic function was measured visually and by Simpson’s method. The strain and strain rate of 6 different basal and 6 mid-myocardial segments were measured offline by TDI. The mean values of these parameters were compared with normal reference values using one sample T-test leading to a significant reduction (P<0.05). Result The most common symptom was dyspnea. Nineteen (46.3%) patients were in NYHA function class II and 10 (24.4%) patients had a history of syncope. Mean left ventricular ejection fraction was 55% ± 4.9%. Considering an LVOT gradient >30mmHg, HCM was found in 18 (43.9%) patients. The mean myocardial wall thickness was 2 ± 0.7 cm. Mean of strain and strain rate were significantly reduced compare with normal values (P < 0.001). In all of the 12 segments, mean ± SD of strain was -10.6 ± 3.8 and that of strain rate was -0.73 ± 0.73. Conclusion TDI, strain, and SR analysis have better diagnostic yield in HCM patients. They are significantly reduced in all HCM patients, even in patients with a normal global systolic function.

Background Left and right ventricular systolic and diastolic functions are contributors to the symptoms and prognosis in adults with congenital heart disease. Echocardiography is a simple tool to evaluate the ventricular function. Tissue Doppler imaging (TDI) may be a good complement in adult congenital heart disease given the altered geometry of the ventricles. Method Forty-seven consecutive patients (29 male, mean age= 20 ± 3 years) presenting to the Adult Congenital Heart Disease clinic were evaluated by conventional echocardiography and TDI to assess the right and left ventricular systolic and diastolic functions and their relation with subjective functional class (FC). Result Six (12.8%) patients had left ventricular ejection fraction (LVEF) <50%; eleven (23.4%) patients had moderate RV systolic dysfunction, and one (2.1%) patient had severe RV dysfunction. Those patients with at least FC II had a significantly lower LVEF (P=0.001) and RVEF (P=0.007) comparing with asymptomatic patients or those with FC I. By TDI, those who had RV Ea (early diastolic myocardial relaxation velocity) Conclusion Left and right ventricular dysfunctions have significant correlations with FC in adult congenital heart diseases. TDI may improve conventional echocardiography in the assessment of the ventricular function.

Background Given the importance of the effect of muscle relaxants on extubation time in coronary artery bypass grafting patients, we sought to assess the difference in “time to extubation” and “intensive care unit length of stay” between the primary bolus doses of pancuronium and cisatracurium, without using maintenance doses during the operation. Method This double-blind clinical trial divided 110 patients into two equal groups, receiving either cisatracurium or pancuronium. The patients’ surgical and cardiopulmonary bypass variables were evaluated, and extubation time and ICU length of stay were compared between the two groups. Result There was no difference between the two groups regarding the depth of anesthesia, train-of-four (TOF) scores at the beginning of anesthesia, and the surgical and cardiopulmonary bypass variables. However, the cisatracurium patients were extubated earlier and had shorter ICU length of stay than the pancuronium patients Conclusion An appropriate depth of anesthesia facilitates the administration of the induction dose of cisatracurium, which confers earlier extubation and shorter ICU length of stay in comparison to pancuronium.

Background Little is known about the prevalence of atrial thrombosis in atrial flutter undergoing cardioversion of rhythm. Several studies, however, have shown that patients with atrial fibrillation have a high prevalence of atrial thrombosis, strongly associated with increased risk of embolism in atrial fibrillation. Still, the incidence of atrial thrombi in patients with atrial flutter is not well established. Method Transesophageal echocardiography was done in 30 consecutive non-anticoagulated patients with a mean age of 48.4 years who were admitted for cardioversion of atrial flutter. Mean left atrial size was 4.3cm and mean ejection fraction was 42%. The mean duration of flutter was more than 48 hours. Left atrial thrombus was seen in 2 patients. Result Two patients had left atrial thrombosis and both of them had rheumatic mitral stenosis. The other patients were free of thrombosis. Conclusion This study suggests that atrial thrombus is uncommon in patients with atrial flutter, and there is a low risk of thromboembolism after cardioversion, except in rheumatic mitral stenosis, which itself has a high prevalence of left atrial thrombosis

Background Up to 30% of patients with heart failure fail to respond to cardiac resynchronization therapy. This study was aimed at assessing the role of low-dose dobutamine stress echocardiography along with tissue Doppler imaging indices to predict response to cardiac resynchronization therapy. Method Twenty-one consecutive patients with systolic heart failure who were candidates for cardiac resynchronization therapy were prospectively included. Contractile reserve was assessed by low-dose dobutamine stress echocardiography (cut-off: 5 and 10%). Interventricular and intraventricular dyssynchrony (using 6 basal, 6 mid-segmental models) was assessed. Acute post-cardiac resynchronization therapy response was defined by 15% or more decrease in the left ventricular end systolic volume. Sensitivity, specificity, predictive values, and likelihood ratios were calculated for the tests singly and in combination. Result Low-dose dobutamine stress echocardiography had the highest specificity (80%) and positive likelihood ratio (2.5), but interventricular dyssynchrony exhibited the highest sensitivity (83.3%) and the lowest negative likelihood ratio (0.4) for predicting positive response to CRT. Conclusion Inotropic contractile reserve assessed by low-dose dobutamine stress echocardiography strongly predicts acute response to cardiac resynchronization therapy.

Most patients with hypertrophic cardiomyopathy (HCM) have asymmetric septal hypertrophy; and among them, 25% present dynamic left ventricular outflow tract obstruction. Apical HCM is unusual. Echocardiography has been the first imaging method for patients with suspected HCM, but its shortcomings in evaluating the apex are well known. We present a 56-year-old woman with a history of left hemithorax pain for five years and myocardial perfusion defect in the inferoseptal region, who was a candidate for selective coronary angiography. On echocardiography, a mildly thickened apex was mistaken for apical foreshortening on planar imaging, but contrast echocardiography revealed apical HCM.

The most common embryological abnormality of the aortic arch is an aberrant right subclavian artery, which occurs in 0.5% to 1.8% of the population. Normally, this anomaly causes no symptoms, but sometimes it can produce a vascular ring. We had two severely symptomatic children with dysphagia and cough from early infancy. They underwent surgery via left thoracotomy and division of the aberrant right subclavian artery, releasing it from behind the esophagus. The patients had a good postoperative course and tolerated a regular diet without further symptoms of dysphagia.

Pericardial effusion is a common finding in hypothyroidism patients. We had three cases of hypothyroidism with cardiac manifestations of massive pericardial effusion accompanied by echocardiographic evidence of tamponade. After diagnosis, pericardiocentesis and treatment with hormonal drugs were commenced, as a result of which the symptoms were alleviated. Tamponade is a serious, albeit rare, clinical manifestation of hypothyroidism. It is, therefore, advisable that hypothyroidism be considered in all patients with pericardial effusion.

We present a 56-year-old woman who came to the emergency department with an exertional dyspnea of recent onset. A transthoracic echocardiographic examination revealed two round masses in her left atrium with mild mitral stenosis and mild-to-moderate mitral valve regurgitation. Her laboratory data were unremarkable except for a mild anemia. Surgical excision of the masses was performed, and two creamy-white fleshy tumors were removed. On cross section, they were solid and creamy-brown with gritty areas. Histopathological examination showed extensive sheets of round to oval cells, and hemangiopericytoma-like patterns. Also, multiple lobules of well-differentiated hyaline cartilage were present. An immunohistochemistry (IHC) panel revealed that the chondroid areas were reactive for S100 protein. The round cells expressed CD99 with focal positivity for NSE (neuron-specific enolase), but were negative for the following cytokeratin, CD34, factor VIII, actin, and desmin. Therefore, the cells were mesenchymal in origin with chondroid differentiation, and the final diagnosis was a mesenchymal chondrosarcoma. A full-scale investigation into the source of the tumor was unrevealing. Shortly after her discharge from the hospital, she developed an embolic cerebrovascular accident.