Reperfusion of infarct related artery achieved by direct percutaneous transluminal coronary angioplasty counteracts left ventricular remodeling afteracute myocardial infarction more than thrombolysis

The purpose of this study was to compare the effect of direct percutaneous transluminal coronary angioplasty (PTCA) and intravenous recombinant tissue plasminogen activator (rt-PA) on left ventricular remodeling in patients w ith acute myocardial infarction (AMI). To address this issue, patients with AMI randomly assigned to direct PTCA or intravenous rt-PA as part of a lar ge multicenter study (Global Utilization of Streptokinase and Tissue Plasmi nogen Activator for Occluded Coronary Arteries [GUSTO] IIb Angioplasty Subs tudy) were evaluated with two-dimensional echocardiography at predischarge, An echocardiographic infarct size index and the end-diastolic and end-syst olic left ventricular volumes were computed. Patients with art infarct size index equal to or higher than the mean value were considered to have a lar ge infarction. Of 26 enrolled patients, 13 were assigned to PTCA (9 success fully reperfused: i.e., TIMI-3 flow after PTCA) and 13 to It-PA (10 success fully reperfused: i.e., ST resolution after rt-PA). In patients considered successfully reperfused, end-systolic volumes tended to be lower in PTCA pa tients than in rt-PA patients (43 +/- 17 cc vs 59 +/- 21 cc, P = 0.09), alt hough there were no differences in infarct size index (7.3 +/- 2.8 vs 7.0 /- 2.8) and ejection fraction (52% +/- 10% vs 46% +/- 12%). End-systolic vo lume depended on infarct size index in the overall patient population (r = 0.60 P = 0.007) and in rt-PA patients (r = 0.80 P = 0.005), while no correl ation was found in PTCA patients. Considering patients with large AMls, end -systolic volumes were higher in the four patients treated with rt-PA than in the four patients treated with direct PTCA (P < 0.01). Considering all t he 26 enrolled patients, these differences were also present, but they did not reach statistical significance, In conclusion, our results suggest that , in patients with large AMls, adequate reperfusion obtained by direct PTCA has a more mal-ked effect in counteracting ventricular remodeling than tha t obtained by systemic rt-PA. This beneficial effect of direct PTCA, indepe ndent of any reduction in regional wall-motion abnormalities, should be tak en into account when comparing the clinical value of direct PTCA with that of systemic thrombolysis in the treatment of AMI.