TRANSFER-AMI: In STEMI, Postlytic Transfer for PCI Is Best

CHICAGO — Transfer of patients with ST-elevation MI to a center where they can routinely undergo percutaneous coronary intervention within 6 hours after getting thrombolytic therapy at a non-PCI hospital was superior to the conventional wait-and-see strategy.

“Transfer to PCI centers should be initiated immediately after thrombolysis without waiting to determine whether reperfusion will be successful or not. Regional systems should be developed to ensure timely transfers,” Dr. Warren J. Cantor said at the annual meeting of the American College of Cardiology.

TRANSFER-AMI (Trial of Routine Angioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction) involved 1,059 patients with STEMI. All had high-risk features and presented to hospitals without a cardiac catheterization facility. In accordance with guidelines, they received thrombolytic therapy along with aspirin, clopidogrel, and unfractionated heparin or enoxaparin.

Subjects were then randomized either to transfer for PCI and stenting within 6 hours of thrombolytic therapy or to transfer only for rescue PCI in the event of failed reperfusion, with elective PCI encouraged after 24 hours in successfully reperfused patients. The latter approach is standard in MI patients unable to undergo timely primary PCI.

Median time from symptom onset to administration of the thrombolytic tenecteplase was 2 hours. Median time from thrombolysis to PCI was 4 hours in the early transfer group, compared with 27 hours in the roughly 60% of patients in the wait-and-see group who eventually underwent PCI, explained Dr. Cantor of Southlake Regional Health Centre, Newmarket, Ont.

The primary end point in TRANSFER-AMI was a composite of 30-day death, reinfarction, heart failure, cardiogenic shock, or recurrent ischemia. The end point occurred in 10.6% of patients given the pharmacoinvasive strategy and in 16.6% who received the standard approach, for a 46% relative risk reduction. Rates for 30-day moderate and major bleeding were similarly low in both groups.

Discussant Dr. Dariusz Dudek said TRANSFER-AMI mainly differed from prior similar trials, which had contradictory results, in its use of state-of-the-art medications and stents.

In particular, dual antiplatelet therapy was used to blunt the coagulation cascade that peaks roughly 90 minutes after thrombolysis and was key to making early PCI safe. Also, using an age-adjusted clopidogrel loading dose (75 mg in patients older than age 75 years, 300 mg in others) was very smart, added Dr. Dudek of the Institute of Cardiology, Kraków, Poland.

In an interview, Dr. William W. O'Neill predicted that TRANSFER-AMI will change management for the roughly 50% of U.S. patients with MI who come to hospitals without catheterization labs.

“There's been a lot of reluctance at small hospitals to routinely transfer patients after lytic therapy. Now we're saying, give lytics and then routinely send everybody. I think this is really going to change the way that small community hospitals practice,” said Dr. O'Neill, professor of medicine and executive dean of clinical affairs at the University of Miami.

Dr. Cantor has served as a consultant to Roche, which, together with the Canadian Institutes of Health Research, funded TRANSFER-AMI.

STEMI patients should be sent to PCI centers after thrombolysis without waitng to see if reperfusion is successful. DR. CANTOR