Myocardial salvage with direct coronary angioplasty for acute infarction.

To assess the changes in myocardial function following direct coronary angioplasty, we evaluated 323 consecutive patients undergoing coronary angioplasty without antecedent thrombolytic therapy for acute myocardial infarction. Left ventricular function was evaluated using contrast ventriculography immediately preangioplasty and at the time of predismissal follow-up angiography (a mean of 7 days after infarction). The global ejection fraction increased from 52.6% to 58.9% (p less than 0.0005). Multivariate correlates of improved global left ventricular function included baseline ejection fraction less than or equal to 45%, and a patent infarct vessel at the time of predischarge follow-up angiography. Systolic function in the infarct zone improved by a mean of 30%. Logistic regression analysis identified sustained infarct vessel patency and anterior myocardial infarction as multivariate correlates of improved regional function in the infarct zone. In patients presenting with baseline ejection fractions less than or equal to 40%, the mean ejection fraction increased from 28% to 42%. Long-term survival was compromised in patients with global ejection fractions of less than or equal to 40% at the time of dismissal. Thus significant improvement in left ventricular function can be expected in the majority of patients undergoing direct infarct angioplasty. The myocardial salvage appears to be most significant in patients suffering large infarctions, and in those with sustained infarct vessel patency.