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 is superior to the conventional wait-and-see strategy, according to the findings of a landmark Canadian trial.
“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 transfer of STEMI patients to PCI centers,” Dr. Warren J. Cantor said at the annual meeting of the American College of Cardiology.
He presented the results of TRANSFER-AMI (Trial of Routine Angioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction).
The study involved 1,059 patients with STEMI with high-risk features who presented to hospitals lacking a cardiac catheterization facility, where, in accordance with current guidelines, they received thrombolytic therapy along with aspirin, clopidogrel, and unfractionated heparin or enoxaparin.
They were then randomized to transfer for PCI and stenting within 6 hours of thrombolytic therapy—the so-called pharmacoinvasive strategy—or to the widely utilized strategy of transfer only for rescue PCI in the event of failed reperfusion, with elective PCI encouraged after 24 hours in successfully reperfused patients, which has been the standard approach in MI patients who cannot undergo timely primary PCI.
The median time from symptom onset to administration of the thrombolytic tenecteplase was 2 hours. The 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, in Newmarket, Ont.
The primary end point in TRANSFER-AMI was a composite of 30-day death, reinfarction, heart failure, cardiogenic shock, or recurrent ischemia. It occurred in 10.6% of patients who received the pharmacoinvasive strategy, compared with 16.6% who were managed using the standard approach, for a highly significant 46% relative risk reduction.
Rates for 30-day moderate and major bleeding were similarly low in both groups. The intracranial hemorrhage rate was 0.2% in the pharmacoinvasive group, and 1.2% with the standard approach.
In an interview, Dr. William W. O'Neill predicted that TRANSFER-AMI will result in a major change in management for the roughly 50% of U.S. patients with MI who come to hospitals without catheterization laboratories.
“TRANSFER-AMI is going to make a big difference because 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, who is a vocal advocate for regionalization of MI care who is professor of medicine and executive dean of clinical affairs at the University of Miami.
Dr. Cantor said he has served as a consultant to Roche, which, together with the Canadian Institutes of Health Research, funded TRANSFER-AMI.
Transfer to PCI centers should be immediate, without waiting to determine whether or not reperfusion will be successful. DR. CANTOR