Perforation of interventricular septum in acute myocardial infarction.

Eight cases of ruptured interventricular septum associated with myocardial infarction were diagnosed at Siriraj Hospital between 1985-1995. Clinical congestive heart failure and holosystolic murmur were found in all. Diagnosis was confirmed by echocardiogram and right heart catheterization in all patients. Two patients died from congestive heart failure preoperatively and the third case died from organ failure and sepsis postoperatively. Another five cases underwent successful ventricular septal defect closure and coronary artery bypass with good results.

Relationship between exercise capacity and left ventricular function in aortic and mitral regurgitation.

The exercise capacity as assessed by treadmill exercise or functional class from clinical history cannot predict standard echocardiographic findings in patients with AR/MR, in terms of EF, LVDs, ESVI. Therefore, exercise capacity cannot be used to predict the timing for surgery in those patients. However, symptomatic patients with dilated LV usually have low LVEF such as in our group.

Prevalence of coronary artery disease in patient with valvular heart disease.

The prevalence of coronary artery disease in valvular disease was 10.9 per cent. The prevalence of coronary artery disease was more common in males, increasing age, aortic valvular disease and mitral regurgitation with chest pain, other types of valvular lesions did not correlate with the presence of coronary artery disease. The prevalence of significant coronary artery disease especially three vessel disease was relatively rare in those aged < 50 years. We recommend performing coronary arteriography only in patients aged > 50 years regardless of symptoms of chest pain, especially in aortic valvular disease and mitral regurgitation.

Prevalence of myocarditis in idiopathic dysrhythmias: role of endomyocardial biopsy and efficacy of steroid therapy.

In order to study the prevalence of myocarditis, EMB was carried out prospectively in 53 consecutive patients with various idiopathic dysrhythmias and efficacy of steroid therapy was evaluated. The patients consisted of 24 males and 29 females with ages ranging between 12 to 80 yrs. Histologic studies revealed myocarditis in 36 per cent. Steroid therapy resulted in good response in 14 of 18 patients (77.8%) with biopsy-proven myocarditis and in 5 of 17 patients (29.4%) with biopsy-negative but with clinically suspected myocarditis. The remaining patients did not have good response to steroid and there was 1 sudden death in each group.

Hemodynamic effects of a beta adrenergic blocking agent-atenolol in patients with severe mitral stenosis.

The hemodynamic effects of atenolol, a cardioselective adrenergic blocking drug, were studied in 10 patients with clinically severe mitral stenosis during cardiac catheterization to evaluate the severity of disease before cardiac surgery. At 5 minutes after intravenous injection of 0.1 mg/kg of atenolol, there were significant reductions of heart rate, cardiac index, pulmonary pressure, pulmonary capillary wedge pressure and mitral valve gradient. The right and left ventricular filling pressures were increased slightly. The pulmonary and systemic vascular resistance did not change after atenolol. The PR interval although prolonged significantly was still within normal range. No serious side effects occurred during the post-catheterization 24 hour observation period except for one patient who developed slow ventricular rate (48/min) during the study. The hemodynamic effects of atenolol observed in this study appear to benefit the patients with mitral stenosis by reduction of pulmonary pressure, pulmonary capillary wedge pressure and mitral valve gradient. These hemodynamic changes may, therefore, lead to improvement of pulmonary congestive symptoms.

Endomyocardial biopsy: its diagnostic usefulness.

In order to assess the diagnostic usefulness of EMB in patients with clinically suspected myocardial diseases, with and without heart failure or dysrhythmias, a prospective study was carried out in 84 consecutive patients. With EMB, the histological diagnosis was considered specific in 33 patients (39.3%), confirmative in 12 patients (14.3%) and negative in 39 patients (46.4%). It was found particularly useful in patients with unexplained heart failure and idiopathic dysrhythmias and in the differentiation between restrictive cardiomyopathy and constrictive pericarditis. The procedure can be safely performed with minimal morbidity and there was no mortality in the present study.

Short and long term mortality after acute myocardial infarction as predicted by two-dimensional echocardiography.

We have non-invasively determined the extent of the acute myocardial insult shortly after admission in a large group of patients with acute myocardial infarction. There appeared a fairly sharp distinction between patients with low and high likelihood of in-hospital death and one year mortality on the basis of echocardiographic findings. The use of wall motion score index and ejection fraction in the prediction of short term mortality (in-hospital death) is good, but the prediction of long term mortality is not that good, since several patients survived up to one year even with high wall motion score index (greater than 2.2) or low ejection fraction (less than or equal to 35%) on admission. One-year survival is high up to 90 per cent in patients with low wall motion score index or high ejection fraction on admission.

Two-dimensional echocardiographic detection of in-hospital complications in acute myocardial infarction.

The two-dimensional echocardiogram is an ideal noninvasive method for evaluation of the global and regional wall function of left ventricle particularly the apical part in the early phase of acute myocardial infarction. Apical dysfunction, right ventricular infarction, left ventricular thrombi can be detected by 2D-Echo. It is especially useful in the identification of a high risk group of patients with acute myocardial infarction, as a guideline for attempting different therapeutic modalities in these patients.