Risks of stopping antiplatelet therapy after stenting

This paper studied the effect of stopping antiplatelet therapy following stent placement. 

A stent is a small device placed in blood vessels to allow blood to flow. Stents can be bare-metal (mesh wire) or drug-eluting (releases medication to block scar tissue from forming). After a stent is inserted, patients receive dual antiplatelet therapy to prevent blood from clotting and obstructing blood flow. Early reports suggest that stopping dual antiplatelet therapy early was associated with an increased risk of stent thrombosis (blood clotting due to stent). 

This study examined the association between stopping antiplatelet treatment and future coronary events.

5392 patients received bare-metal stents while 5078 patients received sirolimus (Rapamune)-eluting stents. At 1 year, 67.3% of patients who received sirolimus-eluting stents and 33.4% of patients who received bare-metal stents received dual-antiplatelet therapy. At 5 years, 48.7% of patients who received sirolimus-eluting stents and 24.3% of patients who received bare-metal stents received dual-antiplatelet therapy.

Among patients who received sirolimus-eluting stents, the occurrence of stent thrombosis was higher among patients who did not receive antiplatelet therapy than patients who did. Discontinuation of both aspirin and thienopyridines (class of drugs) was associated with significantly higher risk for stent thrombosis from 1 month to 4 years after stent placement.

Among patients who received the bare-metal stent, the higher risk of stent thrombosis among patients who did not receive antiplatelet therapy was only seen from day 31 to 180. The overall occurrence of stent thrombosis was very low.

Patients who did not receive antiplatelet therapy were more at risk of a heart attack compared to patients who received antiplatelet therapy. Patients who did not receive antiplatelet therapy were more at risk of stroke compared to patients who received antiplatelet therapy. The type of stent placed did not affect the results. 

The authors concluded that stopping both aspirin and thienopyridines treatment was associated with increased risk for stent thrombosis, heart attack and stroke beyond 1 month after stent placement. 

Discuss antiplatelet therapy with your physician.