Preservation of global and regional left ventricular function after early thrombolysis in acute myocardial infarction

Abstract

The effect of early myocardial reperfusion (within 4 hours after onset of symptoms) on regional left ventricular function in patients with acute myocardial infarction has been quantitated by analysis of segmental wall motion. Of 533 patients randomized either to conventional coronary care unit therapy or to a reperfusion strategy, in 332 high quality angiograms were obtained 2 to 8 weeks after the onset of myocardial infarction. In those assigned to thrombolytic therapy, angiographic data were also available after acute reperfusion. Analysis on an "intention to treat" basis revealed significant preservation of left ventricular function after thrombolytic therapy (ejection fraction 53%) compared with conventional treatment (ejection fraction 47%). In addition, wall motion analysis showed significant improvement of regional function in the infarct zone in both inferior and anterior infarction. In addition, significant changes occurred in regional function of the remote "noninfarct zone" in the acute as well as the chronic stage. It is concluded that improved regional and global left ventricular function can be achieved with early reperfusion and that this is the likely explanation for the reduction of early and late mortality after thrombolysis observed in this study.

Reperfusion failure: a study using electrocardiographic criteria

“…Myocardial necrosis is a process that increases with the elapse of time, with the muscle fibre passing through the stages of dysfunction, stunning and finally death. 13 This was corroborated in our study in which the mean Symptom Needle (S/N) time in the successful group was 3.03 hours as opposed to 7.95 hours in the group, which failed reperfusion. Even in the developed world, the time to admission and the time to treatment in patients admitted with MI is still prolonged, and resources must be allocated to improve these times.…”

Long-term Implications of Reocclusion on Left Ventricular Size and Function After Successful Thrombolysis for First Anterior Myocardial Infarction

“…[48][49] However, the recovery of this salvaged myocardium is sig nificantly impaired by reocclusion.15*16-50 Two previous clinical studies,15-16 both performed shortly after myocar dial infarction, reported that left ventricular function was significantly better in patients without reocclusion than in those with reocclusion. This difference was largely due to recovery of infarct-zone function in patients without reoc clusion.…”

Coronary Blood Flow Assessment After Successful Angioplasty for Acute Myocardial Infarction Predicts the Risk of Long-Term Cardiac Events

“…2 The subsequent quality of coronary flow appears to be an important prognostic factor. 3 However, angiographic success does not necessarily equate with adequate myocardial perfusion, even after early revascularization.…”