Antiplatelet therapy discontinuation and stent thrombosis after sirolimus-eluting stent implantation: five-year outcome of the j-Cypher Registry.

BACKGROUND

The influence of antiplatelet therapy discontinuation on the incidence of stent thrombosis, especially very late stent thrombosis, after drug-eluting stent implantation has not been yet fully addressed.

METHODS

Relationship between antiplatelet therapy discontinuation and stent thrombosis up to 5years was evaluated in 12,812 consecutive patients undergoing sirolimus-eluting stents (SES) implantation in the j-Cypher registry. Data on status of antiplatelet therapy during follow-up were collected prospectively.

RESULTS

Median follow-up interval was 1699days (interquartile range, 1184-1928days). Incidences of definite stent thrombosis were 0.34% at 30days, 0.55% at 1year, and 1.6% at 5years. Dual antiplatelet therapy was maintained in 97.4%, 63%, and 43.9% of patients at 30days, 1year, and 5years, respectively. The rates of stent thrombosis in patients who discontinued both thienopyridine and aspirin were significantly higher in the time intervals of 31-365days, 2-3years and 3-4years, and tended to be higher in the time intervals of 1-2years and 4-5years than those in patients who continued both (31-365days: 1.26% versus 0.2%, P<0.001; 1-2years: 0.59% versus 0.15%, P=0.06; 2-3years: 1.35% versus 0.2%, P=0.004; 3-4years: 1.09% versus 0.25%, P=0.0496; 4-5years: 1.35% versus 0.43%, P=0.17). Patients who discontinued either thienopyridine or aspirin only did not have an excess of stent thrombosis in any time intervals.

CONCLUSIONS

In conclusion, discontinuation of both thienopyridine and aspirin, but not discontinuation of thienopyridine or aspirin only, was associated with an increased incidence of late and very late stent thrombosis up to 5years after SES implantation.