Ticagrelor May Reduce Cardiovascular Events in Patients with Extensive Coronary Artery Disease

Results from a substudy of the PLATO trial presented at the American Heart Association 2012 Scientific Sessions show that patients with extensive coronary artery disease (CAD) have high rates of recurrent cardiovascular events, death, and bleeding, and may benefit from treatment with ticagrelor.

In a poster presentation at AHA 2012 titled “Extent of Coronary Artery Disease and Outcomes After Ticagrelor Administration: Insights from The PLATelet Inhibition and Patient Outcomes (PLATO) Trial,” lead author Emmanouil S. Brilakis, MD, PhD, Director of the Cardiac Catheterization Laboratories at VA North Texas Healthcare System and an Associate Professor of Medicine at University of Texas Southwestern Medical School, and colleagues looked at the effects of more potent treatments than clopidogrel in patients with extensive coronary artery disease (CAD).

In this substudy of the PLATelet inhibition and patient Outcomes (PLATO) trial, researchers examined the effects of treating at-risk CAD patients with ticagrelor, a platelet aggregation inhibitor, and clopidogrel, an oral, thienopyridine-class antiplatelet agent.

Researchers classified patients into two groups: one group had extensive CAD (defined as three-vessel disease, left main disease, or prior coronary artery bypass graft surgery), the second group of patients did not. The study’s primary and secondary end points were compared using the Cox proportional hazards (survival) regression model.

Out of 15,388 patients with CAD, 4,644 (30%) had extensive CAD. However, fewer patients with extensive CAD underwent percutaneous coronary intervention (58%) as compared to those without CAD (79%, P<0.001). More patients with extensive CAD underwent coronary artery bypass graft surgery (16% vs. 2%, P<0.001).

Patients with extensive CAD had more high-risk characteristics at the beginning of the study’s inclusion. They also experience more clinical events during the study’s follow up.

Ticagrelor, compared to clopidogrel, reduced a composite measure of cardiovascular death, myocardial infarction, and stroke in patients with extensive CAD (14.9% vs. 17.6%). Rates of reduction were similar in patients without extensive CAD (6.8% vs. 8.0%).

Rates of major bleeding were similar with ticagrelor vs. clopidogrel among patients without extensive CAD (7.3% vs. 6.4%) and with extensive CAD (25.7% vs. 25.5).

The study authors concluded that high-risk CAD patients have high rates of recurrent cardiovascular events, death, and bleeding. However, patients with extensive CAD and those without extensive disease “display a reduction by ticagrelor relative to clopidogrel for ischemic events with bleeding similar to clopidogrel.”