Trials show deferred stenting, early anticoagulation offer benefit

SAN FRANCISCO — Two trials are giving support for novel treatment approaches to certain PCI patients. The DEFER-STEMI trial showed that in selected STEMI patients, deferring stenting for several hours can reduce no-reflow incidence and improve myocardial salvage following the procedure, and the EUROMAX study showed that bivalirudin initiated in the prehospital setting can improve outcomes. Both trials were discussed at TCT 2013.

In the DEFER-STEMI trial, Colin Berry, PhD, from the University of Glasgow, Scotland, described a technique meant to reduce the risk for no-reflow after primary PCI, which is a cause of adverse outcomes including HF and death.

“To a great extent, no-reflow is predictable,” he said, based on the duration of ischemia, thrombus burden and other factors.

Berry discussed results of the trial, which randomized 101 STEMI patients to either usual care involving immediate PCI (n=49) or deferred stenting between 4 and 16 hours later (n=52). The results showed that deferred stenting did reduce the incidence of the primary endpoint of no- or slow-reflow (TIMI <3); 29% of immediate stenting patients had TIMI <3 compared with 6% of deferred stenting patients (P=.006). No-reflow (TIMI 0/1) showed a trend, but did not reach significance in favor of deferred stenting (P=.054), and intraprocedural thrombotic events were significantly better in the deferred group (P=.008). Myocardial salvage measured by MRI was significantly better in the deferred group, as was the myocardial salvage index.

“Based on our experience, the intervention is novel, pragmatic, and theoretically widely applicable to prevent this adverse outcome during primary PCI,” Berry said. He noted that several other trials are ongoing that will test other timings and settings for deferred PCI.

The HORIZONS-AMI trial established the role of bivalirudin (Angiomax, The Medicines Company) in PCI, and showed its ability to reduce mortality and bleeding up 3 three years when compared with unfractionated heparin and glycoprotein inhibitors (GPI). Some questions remained, however, according to P. Gabriel Steg, MD, of Hopital Bichat-Claude Bernard, Paris, who presented new EUROMAX data at TCT 2013. Questions included the role of bivalirudin in pre-hospital/ambulance or non-PCI hospital settings, as well as the potential of the agent to reduce the risk for acute stent thrombosis with a prolonged infusion.

EUROMAX randomized 2,218 patients in nine European countries to unfractionated heparin/low–molecular-weight heparin and GPI (n=1,109 patients) or bivalirudin (bolus and prolonged optimal infusion, n=1,089 patients). The primary endpoint, death or major bleeding at 30 days, was significantly improved in the bivalirudin group. The secondary endpoint of death, reinfarction or major bleeding at 30 days, was also better in the bivalirudin group, at 6.7% vs. 9.1% (P=.03). Neither cardiac nor non-cardiac death, however, was significantly different between the groups. Acute stent thrombosis, however, was more common in the bivalirudin group, occurring in 17 patients (1.6%) vs. six patients (0.5%) in the control group (P=.02).

Steg noted several limitations to the trial, including its open-label design, but concluded that prehospital bivalirudin provides clear benefit with regard to major events, driven primarily by large reduction in major bleeding.

“We believe that this will be useful in informing practice for the prehospital management of these patients,” Steg concluded.

For more information:

Berry C. With effective upfront pharmacotherapy, should primary PCI be deferred?

Steg PG. Upstream bivalirudin: Insights from EUROMAX. Both presented at: TCT 2013; Oct. 27-Nov. 1, 2013; San Francisco.

Disclosure: Berry reports receiving consulting fees/honoraria from AstraZeneca and St. Jude Medical. Steg reports stockholdings in aterovax and receiving speaking or consulting fees from a number of companies.