Treatment with lytics or primary
percutaneous coronary interventions (PCI) reduces the mortality rate of patients with
ST-elevation myocardial infarction (
STEMI) presenting within 12 hours. Patients presenting >12 hours are generally considered to be ineligible for reperfusion
therapy, and there are currently no specific treatment recommendations for this subgroup.Methods- All patients with
STEMI <24 hours were included in the Treatment with
Enoxaparin and
Tirofiban in Acute
Myocardial Infarction (TETAMI) randomized trial or registry. Those patients who were ineligible for acute reperfusion, had no
cardiogenic shock, and were not planned for revascularization within 48 hours were randomized to 1 of 4 antithrombotic regimens involving
enoxaparin or
unfractionated heparin (UFH), in combination with
tirofiban or placebo for 2 to 8 days. A concurrent registry tracked
STEMI patients coming in within <12 hours, and who underwent reperfusion. This registry also tracked the remaining
STEMI patients who neither received reperfusion nor were enrolled in the TETAMI randomized trial. The demographics and clinical outcomes of all three groups (received reperfusion
therapy, too late for reperfusion and enrolled in the randomized trial, neither received reperfusion
therapy nor were enrolled in the randomized trial) were prospectively tracked.
RESULTS AND CONCLUSIONS: There were 2,737 patients who presented with
STEMI or a new left branch bundle block (LBBB), of which 1,654 (60%) presented < or =12 hours. There were 1,196 (72%) of 1,654 patients who received reperfusion
therapy. There were 458 (28%) of the 1,654 patients deemed "ineligible" for reperfusion, mostly because of a
contraindication to lytics or for being "too old." In contrast, 1,083 (40%) of 2,737 patients presented >12 hours. Apart from 34 of these patients who had a
stuttering infarction and were referred for reperfusion, the remaining patients did not receive reperfusion
therapy. Registry patients who received reperfusion
therapy, compared with TETAMI randomized patients (all of whom received antithrombotic
therapy) and registry patients who did not receive reperfusion, were younger (61 years versus 63 years and 67 years), were more likely to be male (78% versus 73% and 63%), and had persistent ST-segment elevation as opposed to LBBB or Q waves. Registry patients who received reperfusion
therapy had better clinical outcomes, even after adjusting for admission Killip class, compared with TETAMI randomized patients and registry patients who did not receive reperfusion
therapy. TETAMI randomized patients had better outcomes than registry patients who did not receive reperfusion
therapy. The major obstacle to expanding the delivery of reperfusion
therapy to patients with
STEMI is the large fraction of patients who present too late for reperfusion
therapy. Examination of prospectively gathered data on
STEMI patients who are ineligible for reperfusion may help optimize their treatment.