Beneficial impact of prolonged dual antiplatelet therapy after drug-eluting stent implantation.

Background:  Twelve-month dual antiplatelet therapy (DAT) with aspirin and clopidogrel after drug-eluting stent (DES) implantation is routinely recommended. It is unclear if prolonged (>12-month) DAT is also favorable. We compared the outcome of patients discontinuing DAT 12 months after off-label DES implantation versus those with DAT for >12 months.

Methods:  Baseline, treatment, and outcome data of patients undergoing off-label DES implantation and free from events 11.5 months after index procedure were retrospectively retrieved. Those discontinuing DAT between 11.5 and 12.5 months (12-month DAT group) were compared to those discontinuing DAT after 12.5 months (>12-month DAT group). The primary end-point was the long-term (>24-month) rate of major adverse cerebro-cardiovascular events (MACCE).

Results: Two hundred seventy-two patients met study inclusion criteria: 133 (48.9%) in the 12-month DAT group and 139 (51.1%) in the >12-month DAT group (who were on DAT for an average of 24 months). After an average of 36 months after DES implantation, 14 patients (5.1%) developed MACCE, with 6 (3.5%) cardiac deaths, 7 (2.2%) myocardial infarctions, no stroke, and 5 (1.8%) repeat revascularizations. The >12-month DAT group had a significantly lower risk of MACCE (1 [0.7%] vs. 13 [9.8%] in the 12-month DAT group, P < 0.001) and myocardial infarction (0 vs. 7 [5.3%], P = 0.006), with such differences confirmed at multivariable propensity-adjusted analyses. No significant differences in terms of minor or major bleedings occurred.

Conclusions: In this retrospective registry, patients with off-label DES implantation receiving prolonged (>12 months) DAT presented with lower rates of MACCE and myocardial infarction.