Angiographic frame counts 90 minutes after streptokinase predict left ventricular function at 48 hours following myocardial infarction

Objective-To assess whether the 90 minute corrected thrombolysis in myocard ial infarction frame count (CTFC) in the infarct related artery predicts le ft ventricular function at 48 hours in patients with myocardial infarction treated with aspirin, streptokinase, and either heparin or Hirulog. Design and setting-Analysis of 251 patients with acute myocardial infarctio n enrolled in the international, multicentre Hirulog early reperfusion/occl usion (HERO-1) trial, who underwent both 90 minute coronary angiography and 48 hour left ventriculography. Main outcome variables-The CTFC was determined in the infarct related arter y 90 minutes after starting intravenous streptokinase (1.5 x 10(6) U over 3 0 to 60 minutes), and compared with indices of left ventricular function as sessed by contrast ventriculography at 48 hours. Results-A CTFC of less than or equal to 27 frames (previously reported mean + 2 SD in coronary arteries of patients without acute infarction) occurred in 29% of infarct related arteries, and was associated with a lower infarc t zone mean chord score (-2.06 v -2.54, p = 0.01), a lower fraction of chor ds > 2 SD below normal (37% v 51%, p = 0.005), and trends towards higher le ft ventricular ejection fractions (60.9% v 58.2%, p = 0.11) and lower end s ystolic volumes (50.1 ml v 55.9 ml, p = 0.23). A CTFC of less than or equal to 40 at 90 minutes occurred in 50% of infarct related arteries, and was a ssociated with a significantly lower mean chord score (-2.20 v -2.60, p = 0 .02), a smaller fraction of chords > 2 SD below normal (41% v 52%, p = 0.02 5), a smaller end systolic volume (49.1 ml v 59.3 ml, p = 0.02), and a high er left ventricular ejection fraction (60.4% v 56.5%, p = 0.03). Conclusions-The 90 minute CTFC predicts left ventricular function at 48 hou rs following streptokinase. The CTFC associated with better ventricular fun ction may be higher than values determined from a non-infarct population.