Myocardial Performance Index in Patients of Acute Coronary Syndrome.

Evaluation of ventricular systolic and diastolic functions is an essential part of echocardiographic evaluation in a patient of acute coronary syndrome (ACS). Both systolic and diastolic functions change as disease progresses. There are many limitations of the echocardiographic indices of LV functions used routinely in patients of acute coronary syndrome. Tei Chuwa devised a reliable index of myocardial performance (The Tei Index/ Myocardial Perfomance Index). It is a reliable index for evaluation of LV systolic and diastolic performance in acute coronary syndrome. Materials and Methods: 75 patients of acute coronary syndrome and 25 controls were studied. All patients admitted with the complaints of ischemic chest pain were included in the study. An informed consent was taken from all patients. Detailed history and physical examination were carried out and baseline investigations were done. Tei index was calculated from the ratio of time intervals: a-b/b, derived with the aid of pulse doppler echocardiography. Its relationship was studied with acute coronary syndrome and complications after ACS. Results: The Cardiac Output was not significantly different from controls in UA; but it was significantly deranged in STEMI (p<0.001) and NSTEMI (p <0.001). MPI was significantly different in all the three groups from controls. The t and p values of MPI of various groups on comparison with controls were t=9.0, p<0.001; t=12.5, p<0.001; t=18, p< 0.001 for UA, STEMI and NSTEMI respectively. The MPI of STEMI patients was 0.64±0.08 that of NSTEMI patients was 0.57±0.059, that of UA was 0.48±0.06 and that of controls was 0.39±0.04. The correlation showed that MPI was more strongly related to complications as compared to other echocardiographic parameters. Conclusion: MPI is a non-geometric doppler index, that combines systolic and diastolic performance of left ventricle. As compared to controls, MPI was found to be deranged in patients of acute coronary syndrome. when recorded within 24 hours of admission, myocardial performance index was a sensitive and independent predictor of in-hospital events.

A Study on Ventricular Late Potentials by Signal Averaged Electrocardiogram in Myocardial Infarction Patients.

Fifty patients who presented with Myocardial Infarction (MI), diagnosed by history, ECG, enzymes were subjected to late potential analysis between 7-10 days post MI by Signal Averaged Electrocardiography (SAECG). There were 42 male and 8 female patients. 34 had anterior wall MI and 16 had inferior wall MI, and all of them had Q wave infarction. History of previous MI in 12, diabetes in 14, hypertension in 34, smoking in 24 and hypercholesterolemia in 8 was noted. Patients were followed up for one year. Late potentials were positive in 10 patients (62.5%) of inferior wall MI and 6 patients (17.5%) of anterior wall MI. Those with episodes of ventricular tachycardia had increased incidence of late potentials. There was no correlation of late potentials and LV function assessed by echocardiography. Thrombolysed group had decreased incidence of late potentials.