USE OF AORTIC COUNTERPULSATION TO IMPROVE SUSTAINED CORONARY-ARTERY PATENCY DURING ACUTE MYOCARDIAL-INFARCTION - RESULTS OF A RANDOMIZED TRIAL

Background Aortic counterpulsation has been observed to reduce the rat e of reocclusion of the infarct-related artery after patency has been restored during acute myocardial infarction in observational studies. To evaluate the benefit-to-risk ratio of aortic counterpulsation durin g the early phase of myocardial infarction, a multicenter randomized c linical trial was performed. Methods and Results Patients who had pate ncy restored during acute cardiac catheterization within the first 24 hours of onset of myocardial infarction were randomly assigned to aort ic counterpulsation for 48 hours versus standard care. Intravenous hep arin was used similarly in both groups and was continued for a median (25th, 75th percentile) of 5 (2,7) days. A total of 182 patients were enrolled; 96 were assigned to aortic counterpulsation and 86 to standa rd care. Repeat cardiac catheterization was performed at a median of 5 (4,6) days after randomization in 89% of patients assigned to aortic counterpulsation and in 90% of control patients. Patients randomized t o aortic counterpulsation had similar rates of severe bleeding complic ations (2% versus 1%), number of units of blood transfused (mean, 1.3/-2.6 versus 0.9+/-1.8 units), and vascular repair or thrombectomy (5% versus 2%) compared with patients treated in a conventional manner. P atients randomized to aortic counterpulsation had significantly less r eocclusion of the infarct-related artery during follow-up compared wit h control patients (8% versus 21%, P<.03), In addition, there was a si gnificantly lower event rate in patients assigned to aortic counterpul sation in terms of a composite clinical end point (death, stroke, rein farction, need for emergency revascuiarization with angioplasty or byp ass surgery, or recurrent ischemia): 13% versus 24%, P<.04. Conclusion s This randomized trial showed that careful use of prophylactic aortic counterpulsation can prevent reocclusion of the infarct-related arter y and improve overall clinical outcome in patients undergoing acute ca rdiac catheterization during myocardial infarction.