Myocardial infarction. correlation with ventricular arrhythmia and left ventricular function

Great effort has been expended on attempts to predict ventricular arrhythmia and left ventricular function; a two major source of mortality in AMI. QT dispersion have been demonstrated to reflect regional inhomogenicity of ventricular repolarization, which is considered a fundamental factor for initiation of ventricular arrhythmia. Prospective study of 27 consecutive patients admitted to CCU with AMI indicated for streptokinase [SK] [21 M/ 6 F, mean age: 50ys] compared with control group of 15 consecutive patient contraindicated for SK [11 M/ 4F, mean age 50 ys] treated by nitroglycerin [NG]. Both groups were matched for age, and site of MI. For both study and control group 12 lead ECG was done on admission, post thrombolytic and at discharge. SAECG, Heart Rate Variability [HRV], 24 hour Holter monitoring and Doppler echocardiography were done only at discharge. QTc calculated as QT int [sec] square root [RR [sec]] QT dispersion [QTd] calculated from 12 lead ECG as difference between maximum QT interval minus minimum QT interval. QTc was not different in both groups on admission and on discharge [0.41 +/- 0.08 vs 0.39 +/- 0.04 in gpI; 0.47 +/- 0.05 vs 0.45 +/- 0.05 in gp. II]. QTd was high in all AMI patient on admission. However, only the thrombolytic therapy caused significant reduction of QTd which was maintained until discharge. SK: Admission: 103 +/- 26.7- Post therapy: 46.6 +/- 18.3- Before discharge 40 +/- 11- P value: 0.0001. NG Admission: 118 + 27.7- Post therapy: 0- Before discharge: 121 +/- 31.5- P value: 0.334. [There is significant difference in both groups as regard EDD in echocardiography where group II had more dilated end diastole than group I.] In 24 hour Holter monitoring, there was significant higher incidence of ischemic ST depression in NG gp than SK gp. [92.3% vs 3.7%, P value: 0.0001]. But there was no significant difference between the two group in SAECG and HRV indices. The SK group with improved QT dispersion showed significantly lower incidence of tachyarrhymia [none vs 66%] lower mortality [non vs 13%] and less LV dilatation [3.7% vs 33.3%]. QTd not QTc serve as a good discrimenant between complicated and non complicated MI. Persistent high QTd could predict more arrhythmia and left ventricular failure. SK therapy not NG is the treatment of choice in AMI for correction of QTd

Enhanced thrombolytic efficacy and reduction of infarct size by simultaneous infusion of streptokinase and heparin

Thirty patients with recent onset acute myocardial infarction admitted to Coronary Care Unit of Ain Shams University Hospital. They divided into two groups. Group I patient received Simultaneous infusion of Streptokinase and heparin and group II patients received streptokinase followed by heparin two hours later. Group 1 showed signs of faster and shorter reperfusion time than group II, with rapid relief of chest pain and earlier peaking of serum creatinine phosphokinase enzyme with lower peak value. As well as rapid resolution of ECG criteria of ischemia and high incidence of reperfusion arrhythmia in group I than in group II. In the same time the segmental wall motion abnormalities were lower in group I than in group II and also the wall motion score index. Group I had better left ventricular function and higher ejection fraction than group II. Thus, the present study showed that simultaneous infusion of streptokinase and heparin early in acute myocardial infarction is better than subsequent infusion of heparin after streptokinase because the former resulted in more rapid recanalization of the infarct related artery, faster repefusion of the affected myocardium, smaller infarcts and better left ventricular function than the latter