Aspirin intolerance and the need for dual antiplatelet therapy after stent implantation: a proposed alternative regimen

Background: Dual antiplatelet therapy (DAT, i.e. aspirin+thienopyridine) has been shown to reduce the risk of stent thrombosis (ST) and myocardial infarction (MI) after coronary stent implantation. Data regarding alternative antiplatelet therapy in patients with allergy or intolerance to aspirin are lacking.

Methods: This study is a retrospective analysis of consecutive patients with adverse reactions to aspirin who received an alternative combination of DAT (indobufen, trapidil, or triflusal in association with a thienopyridine) after elective implantation of either drug-eluting (DES) or bare-metal stents (BMS). Endpoints analyzed were cardiac death, MI, ST and bleeding.

Results: A total of 127 patients undergoing stenting of 267 lesions (DES 84%, BMS 16%), were identified between June'99 and November'08. Reasons for not taking aspirin included gastrointestinal intolerance (53.5%), allergy (39.4%), non-gastrointestinal bleeding (5.5%) and others (1.6%). Aspirin was substituted with indobufen (64.6%), trapidil (26.8%), triflusal (6.3%), or a combination of indobufen+trapidil (2.4%). Median duration of DAT was 369 days [IQR 273-1053] after DES and 46.5 days [IQR 30-699] after BMS implantation. Only 3.1% of patients prematurely discontinued DAT. During a median follow-up of 1161 days [IQR 781-1538], rates of cardiac death and MI were 3.1% and minor bleeding occurred in 1.5%. There was 1 very late definite ST occurring 2 days after DAT discontinuation and no probable ST.

Conclusions: In this cohort of patients with aspirin intolerance undergoing coronary stent implantation, the combination of a thienopyridine with indobufen, trapidil, or triflusal was associated with a low rate of cardiac death, ST and MI.