PCI versus Pharmaco-Invasive Regimen in STEMI Patients

San Francisco—Patients with ST-elevation myocardial infarction (STEMI) treated at community hospitals or in ambulances had similar results whether they underwent percutaneous coronary intervention (PCI) or received a pharmaco-invasive treatment regimen, according to an open-label, prospective, randomized trial.

The primary end point, a composite of all cause death or shock or congestive heart failure or reinfarction up to day 30 after randomization, occurred in 12.4% of patients in the tenecteplase plus enoxaparin, clopidogrel, and aspirin group compared with 14.3% of patients in the PCI group (relative risk, 0.86; 95% confidence interval, 0.68-1.09; P=.24).

Frans Van de Werf, MD, PhD, the study’s lead author, said he could say with 95% confidence that the observed incidence in the pharmaco-invasive group would exclude a 9% relative excess compared with the PCI group. He presented the data in a late-breaking clinical trial session at the ACC meeting. Results were simultaneously published online in the New England Journal of Medicine [10.1056/NEJMoa1301092].

Boehringer Ingelheim, manufacturer of tenecteplase, funded the study. Dr. Van de Werf said the analysis was performed independent of Boehringer Ingelheim at the University of Leuven in Belgium, where he is a professor of cardiology.

In the STREAM [Strategic Reperfusion Early After Myocardial Infarction] trial, 1892 patients were randomized at 99 sites in 15 countries in a 1:1 ratio to undergo primary PCI or to the pharmaco-invasive group, which received tenecteplase plus enoxaparin, clopidogrel, and aspirin. When patients arrived at a hospital with a catheter laboratory, they underwent an electrocardiogram examination. If there was evidence of resolution, patients could not undergo an immediate catheterization; it had to be scheduled 6 to 24 hours after randomization.  

The first patient enrolled in the trial on March 19, 2008, and the study ran through September 7, 2012. Approximately 81% of patients were randomized in ambulance systems, and the remaining 19% were in community hospitals. Of the patients, 751 were from France, followed by Russia (327), Spain (167), Serbia (134), and Canada (92). There were no patients from the United States.

Patients were included if they had STEMI with at least 2-mm ST-elevation in 2 contiguous leads presenting within 3 hours of symptom onset and were unable to undergo primary PCI within 1 hour. The groups were well balanced. The mean age was approximately 60 years, 79% were males, and 10% had previous MI. The only statistically significant difference was that more patients in the PCI group had a history of congestive heart failure.

Dr. Van de Werf said it took approximately 1 hour between symptom onset and the first medical contact, either in the ambulance or hospital. It took another 30 minutes for patients to be randomized.

There were also no significant differences in the individual components of the primary end point. The incidence of all cause death was 4.6% in the pharmaco-invasive group and 4.4% in the PCI group (P=.88), while cardiac death occurred in 3.3% and 3.4% of the patients, respectively (P=.92). In addition, congestive heart failure occurred in 6.1% of patients in the pharmaco-invasive group and 7.8% of the PCI group (P=.18), cardiogenic shock occurred in 4.4% of patients in the pharmaco-invasive group and 5.9% of the PCI group, and reinfarction occurred in 2.5% of patients in the pharmaco-invasive group and 2.2% of the PCI group (P=.74).