TIME TO REPERFUSION WITH DIRECT CORONARY ANGIOPLASTY AND THROMBOLYTICTHERAPY IN ACUTE MYOCARDIAL-INFARCTION

An analysis was performed of the Mayo Clinic randomized trial of direc t percutaneous transluminal coronary angioplasty and tissue-type plasm inogen activator (t-PA) to determine the time required to achieve repe rfusion with direct coronary angioplasty. Because patients in the Mayo trial assigned to t-PA did not undergo protocol coronary angiography, reperfusion rates from the Thrombolysis in Myocardial Infarction (TIM I) I trial in which patients underwent coronary angiography 30, 60 and 90 minutes after thrombolytic therapy were used for comparison. TIMI perfusion grade 2 or 3 flow in the infarct artery was considered to re present reperfusion after thrombolysis. In the 56 patients assigned to t-PA, the mean time from randomization to initiation of the BPA infus ion was 20 minutes. Twenty minutes were therefore added to the previou sly reported 30, 60- and 90-minute reperfusion rates to express these in terms of time from randomization (50, 80 and 110 minutes). in the 4 8 patients who had direct angioplasty, the mean time from randomizatio n to arrival in the cardiac catheterization laboratory was 45 minutes; it took a mean of 6 additional minutes for patients to be prepared an d draped and arterial access obtained, and a mean of 27 additional min utes to complete angiography and achieve reperfusion. At 50, 80 and 11 0 minutes after randomization, the reperfusion rates for direct corona ry angioplasty were 12, 54 and 83%, similar to previously reported TIM I reperfusion rates with t-PA (24, 57 and 71%, respectively, p = NS) b ut significantly greater at 80 and 110 minutes than was reported for s treptokinase (8, 23 and 31%, respectively, p = 0.001). If only normali zation of coronary blood flow (TIMI perfusion grade 3 flow) was consid ered to represent reperfusion, reperfusion rates for direct coronary a ngioplasty would be significantly greater than for either t-PA or stre ptokinase. Thus, direct coronary angioplasty is rapid, and reperfusion rates compare favorably with those reported for thrombolytic therapy.