Gene Variants Behind Stent Thrombosis Identified

Several gene variants that cause stent thrombosis have been discovered by Mount Sinai School of Medicine researchers. Stent thrombosis is a devastating and often deadly complication after coronary stent implantation in people with coronary artery disease.The team found that three of these variants were associated with impaired sensitivity to the common blood thinner clopidogrel, and a fourth that affects a blood platelet receptor involved in platelet aggregation and clot formation. Analyzing these gene variants will help researchers identify patients at risk for early stent thrombosis and take measures to prevent it. The data also provide a clinical and genomic score that indicates the best predictive accuracy for stent thrombosis risk. The findings are published in the October 26 issue of the Journal of the American Medical Association.
Through a partnership with the Institut de Cardiologie at Pitié-Salpêtrière University Hospital in Paris, France, the research team evaluated the DNA of 123 patients who had undergone stent implantation and developed early ST while treated with dual antiplatelet therapy, which is a combination of aspirin and clopidogrel. The patient information was shared as part of ONline ASSIstance for Stent Thrombosis (ONASSIST), a nationwide web registry of patients in France. Looking at 23 genetic variants previously associated with clopidogrel metabolism, platelet receptor function, and the control of blood clotting, they found four that were predictive risk factors of early ST. They also found that a low dose of clopidogrel in combination with a proton pump inhibitor, which is a drug to treat acid reflux, also increased the risk of early ST.