Risk factors and angiographic profile of coronary artery disease in young.

A total of 124 patients of ischaemic heart disease under 40 years of age (96 with myocardial infarction and 28 with angina) were studied for risk factors of coronary artery disease. Electrocardiogram, treadmill test, lipid profile and coronary arteriography were done in all cases. Smoking (56.4%) and hyperlipidaemia (30.6%) emerged as the major risk factors. Further stratification of lipid profile revealed that predictive value of hypercholesterolaemia could be enhanced by considering the different ratios of lipoproteins and indices of atherogenicity. Coronary arteriography revealed a preponderance of single vessel disease (48.4%)-left anterior descending being most commonly involved (71.8%). Increase in low density lipoprotein fraction was related to multivessel involvement.

Evaluation of coronary artery disease by dipyridamole echocardiography test.

Role of oral dipyridamole echocardiography test (DET) was evaluated in 50 patients with effort angina. All patients underwent coronary angiography, the day after oral DET. The echo studies were performed at rest and 65 +/- 15 minutes after 300 mg of oral dipyridamole. Segmental wall motion was analysed in a 16 segment model and a wall motion score index (WMSI) was generated for the entire left ventricle both at rest and following the drug. WMSI was significantly higher after oral dipyridamole, (p < 0.001) compared to resting condition with increased sensitivity (86% vs 74%). When results of DET were compared with coronary angiography, the correlation of WMSI was statistically significant in three vessel disease (p < 0.001), two vessel disease (p < 0.001) as well as for left anterior descending lesions (p < 0.001). However, it was insignificant for single vessel disease, viz, right coronary artery and circumflex artery. Thus we conclude that oral DET is a safe, inexpensive, sensitive and non-exercise dependent method for demonstrating myocardial ischaemia with high diagnostic accuracy.

Effect of intravenous streptokinase on left ventricular function following acute myocardial infarction--an echocardiographic study.

160 patients with first attack of acute myocardial infarction (AMI), admitted within 6 hours after onset of chest pain, were divided into two groups--80 receiving intravenous streptokinase (IVSK, Gr. I) an 80 being treated without IVSK (GR. II). They were studied for pre-discharge (12.5 +/- 2.5 days-post admission) echocardiographic LV function. Gr. I pts received 1.5 million units of IVSK within 6 hrs of onset of chest pain, alongwith beta-blockers, aspirin and heparin unless contraindicated. Gr. II received all these except IVSK alongwith conventional therapy. Highly significant (P < 0.001) improvement was noted in the end-diastolic volume (EDV), end-systolic volume (ESV), Ejection fraction (EF) and regional wall motion score (RWMS) in the anterior wall (AW) AMI group when treated early with IVSK. In the inferior wall (IW) AMI group significant decrease was observed in the EDV and ESV (P < 0.001) and RWMS (P < 0.05), but the difference was not statistically significant for EF. Early high-dose short term IVSK infusion is thus associated with highly significant improvement in LV functions--regional as well as global--especially in AW AMI; in IWAMI the improvement is less marked.

Haemodynamic advantage with single chamber rate responsive pacemakers over dual chamber pacemakers during exercise in chronotropic incompetence.

Sequential cardiac chamber activation and chronotropic response are amongst the important determinants of cardiac performance. This study compared VVIR mode with DDD and VVI mode to assess the contribution of these two factors in the determination of cardiac performance during exercise. Ten patients with a mean age of 68 +/- 5 years were studied during 1988-90, who had complete heart block and sinus node dysfunction with a mean LV ejection fraction of 51.5 +/- 6.25%. Five patients had DDD pacemakers and the rest had VVIR pacemakers. Patients were exercised first in VVI mode followed by either DDD or VVIR mode. Exercise duration, maximum rate pressure product, exercise capacity and cardiac output were measured with graded treadmill test in Bruce protocol. There was remarkable increase in the exercise duration (P < 0.001) and the maximum rate pressure product (P < 0.001) in patients with VVIR as compared to DDD and VVI mode. In DDD mode, as compared to VVI mode, this increase was less remarkable, though statistically significant (P < 0.005). Therefore, it is concluded that patients with chronotropic incompetence as well as complete heart block do better during dynamic exercise when they have VVIR mode compared to VVI or DDD mode.