A systematic review of the efficacy of aspirin monotherapy versus other antiplatelet therapy regimens in peripheral arterial disease.

Background: Dual antiplatelet therapy (DAPT) usually refers to the administration of aspirin plus a platelet P2Y receptor blocker. This combination is commonly prescribed after revascularization procedures in patients with peripheral arterial disease (PAD) to prevent failure of the intervention. However, there is not a consensus among peripheral vascular specialists regarding whether the optimal treatment regimen for their patients is mono antiplatelet therapy (MAPT) or DAPT. Furthermore, there is no consensus regarding the optimal duration of DAPT. This study was undertaken to systematically and critically review the evidence for the use of DAPT after revascularization in PAD, hypothesizing that longer durations of DAPT will result in decreased rates of major adverse cardiac events, major adverse limb events, and mortality, without a significant increase in severe bleeding episodes compared with MAPT or shorter durations of DAPT.

Methods: A systematic search strategy encompassing DAPT and PAD was deployed in two databases. Studies including arterial bypasses using venous or prosthetic conduits, endovascular procedures, diagnostic angiography of lower extremity arteries, and patients with high risk factors were included.

Results: We included 14 studies, 10 of which were randomized controlled trials (RCTs). The overall risk of bias for the RCTs ranged from low to moderate, whereas nonrandomized studies had moderate to high risk of bias. The results of this review suggest that use of DAPT in patients with PAD reduces rates of major adverse cardiac events (risk ratio [RR], 0.79; 95% confidence interval [CI], 0.68-0.91; P = .002), major adverse cardiac and cerebrovascular events, and mortality (RR, 0.57; 95% CI, 0.45-0.72; P < .00,001) compared with those of patients treated with MAPT. Lower extremity-specific end points, such as major adverse limb events and target lesion revascularization (RR, 0.70; 95% CI, 0.49-1.01; P = .06) were also decreased in the DAPT cohort. Rates of moderate bleeding, however, were increased in those treated with DAPT, whereas rates of major bleeding (RR, 0.98; 95% CI, 0.68-1.41; P = .92) remained similar in both treatment groups. The effects of DAPT duration on outcomes of revascularization in patients with PAD have yet to be studied in an RCT.

Conclusions: DAPT appears to be beneficial for preventing complications after revascularization in PAD, including thrombotic failure of the intervention. However, the durations of DAPT use in these studies are heterogeneous, suggesting that additional data are needed to determine the optimal use of DAPT in PAD patients.