he goal of reperfusion therapy for acute myocardial infarction (AMI) is to reestablish Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow 1 in the epicardial infarct-related artery and myocardial reperfusion as early as possible. [2][3][4] Although thrombolytic therapy has the advantage of shortening the time to reperfusion, the rate of achieving TIMI grade 3 flow remains unsatisfactory. In contrast, primary percutaneous coronary intervention (PCI) has the advantage of a higher rate of TIMI grade 3 flow, but the delays prior to reperfusion can be substantial. Therefore, thrombolytic therapy immediately followed by PCI has lately attracted considerable attention as an alternative strategy. [5][6][7][8] Although pre-interventional patency in patients with primary PCI is reported to predict a favorable outcome, 9,10 little is known about the significance of early pre-interventional reperfusion using thrombolytic drugs. We prospectively examined the relationship of infarct size and left ventricular function to TIMI grade flow at 45 min after thrombolysis followed by immediate PCI if the grade flow of the infarct-related artery was TIMI grade 2 flow or less.
Methods
Study PopulationThe study group comprised 134 consecutive patients (mean age 60±9 years [range 36-80]; 113 men, 21 women) admitted to hospital within 6 h of symptom onset from August 2000 through August 2002. Patients were required to have typical chest pain lasting at least 20 min, associated with ST-segment elevation of at least 1.0 mm in at least 2 limb leads, or at least 2.0 mm in at least 2 contiguous precordial leads. Patients were excluded if they had shock, previous cerebrovascular disease, active bleeding lesions, or any other condition that contraindicated thrombolytic therapy. All patients were given 162 mg oral aspirin, 5,000 units intravenous heparin, and 800,000 units (approximately half the standard dose) intravenous monteplase. Monteplase is a mutant tissue plasminogen activator developed in Japan that can be given as a single-bolus intravenous injection. It is characterized by a long alpha half-life and rapid restoration of TIMI grade 2 or 3 flow. 11 Eighty-five patients were also given 200 mg oral sarpogrelate hydrochloride, a serotonin receptor antagonist, as an antiplatelet drug. 12 The protocol was approved by the internal review board of the hospital and all the patients provided written informed consent.
Coronary AngiographyCardiac catheterization was performed immediately after medication. We prospectively evaluated TIMI grade flow in the infarct-related artery 45±3 min after thrombolysis. If TIMI grade flow at this time was 0, 1, or 2, immediate PCI, and 50 patients with TIMI grade 3 flow (group T3) were treated conservatively after thrombolysis. Although the door-to-balloon times did not differ in groups T0 and T2, group T2 had lower peak creatine kinase, a higher rate of complete (≥70%) ST resolution and better regional wall motion at discharge as compared with group T0, similar to group T3 (group T2, group T3 vs group T0...