The effect of intravenous thrombolytic therapy on left ventricular function: a report on tissue-type plasminogen activator and streptokinase from the Thrombolysis in Myocardial Infarction (TIMI Phase I) trial.

Abstract

In Phase I of the NHLBI trial of Thrombolysis in Myocardial Infarction (TIMI), 290 patients admitted within 7 hr after onset of acute infarction were randomly assigned to intravenous treatment with either streptokinase (SK) or recombinant tissue-type plasminogen activator (rt-PA). Left ventricular function was measured from contrast ventriculograms in 145 patients with both pretreatment and predischarge studies analyzable. Regional wall motion in the infarct site was measured by the centerline method and expressed in units of standard deviations (SDs) from the mean motion in 52 normal subjects. Patients treated with rt-PA (n = 77) achieved a significantly higher reperfusion rate after 90 min of treatment. Perfusion of the infarct-related artery improved from visual grade 0 or 1 (total occlusion or penetration without perfusion) to grade 2 or 3 (partial or full reperfusion) in 62% receiving rt-PA vs 31% receiving SK (n = 68) (p < .001). However, the ejection fraction did not change significantly from before treatment to before discharge in either treatment group (+0.7 6.7% vs + 1.0 8.3%, respectively). A small but significant increase in regional wall motion was observed in each of the two groups (+0.4 0.8 vs +0.3 0.8 SD/chord, respectively; each p < .001 compared with baseline). This was countered by declines in the hyperkinesis of the noninfarct region (-0. Analysis of the combined groups revealed that the ejection fraction increased only in patients who achieved reperfusion by 90 min after onset of therapy or who had subtotal occlusions initially. There was greater recovery of left ventricular function in patients who achieved reperfusion earlier vs later than 4 hr after symptom onset and in patients with vs without some collateral circulation to the infarctrelated artery. Circulation 75, No. 4, 817-829, 1987. SINCE the late 1960s, many trials of thrombolytic therapy with streptokinase or urokinase in patients with acute myocardial infarction have been performed. The results have varied widely, both in terms of the degree of reperfusion achieved and clinical benefit, evaluated from mortality, recurrent infarction, or funcFrom the TIMI Coordinating Center, Baltimore.

Early Reperfusion During Acute Myocardial Infarction Affects Ventricular Tachycardia Characteristics and the Chronic Electroanatomic and Histological Substrate

“…The Thrombolysis in Myocardial Infarction scoring system was used to determine the patency of the IRA. 9 Patients were considered reperfused when Thrombolysis in Myocardial Infarction grade 3 flow was present after reperfusion therapy.…”

Influence of coronary collateral vessels on myocardial infarct size in humans. Results of phase I thrombolysis in myocardial infarction (TIMI) trial. The TIMI Investigators.

“…(Circulation 1991;83:739-746) It is well established that coronary collateral blood flow is a major determinant of the extent of necrosis after coronary artery occlusion in experimental animals.1-3 However, the role of coronary collaterals in modulating infarct size in humans ation of kinetics of creatine kinase (CK) release by reperfusion,13-6 and reliance on global left ventricular function parameters despite the poor correlation between recovery of regional wall motion in the infarct site and improvement in global left ventricular ejection fraction after thrombolytic therapy. 17 No previous study has examined the impact of collateral vessels present at the onset of acute myocardial infarction on infarct size, estimated enzymatically, in the absence of any confounding effect due to reperfusion.…”

The impact of right atrial ischemia on inferior myocardial infarction with extension to right ventricle: Transesophageal echocardiographic examination

“…Therefore, without a doubt reperfusion therapy should be applied by any method in this high-risk entity. [27][28][29] …”