P2Y12 inhibitor monotherapy following short-term dual antiplatelet therapy in complex percutaneous coronary intervention: A post-hoc analysis of SMART-CHOICE trial

In patients with complex percutaneous coronary interventions (PCIs), P2Y12 inhibitor monotherapy, mostly clopidogrel, following short-term dual antiplatelet therapy (DAPT) did not increase ischemic events compared with 12 months of DAPT.

Key Takeaway

  • At 1 year, patients with complex PCIs had a higher risk of ischemic events and similar risk of bleeding events than those with non-complex PCIs.
  • P2Y12 inhibitor monotherapy, mostly with clopidogrel, following 3 months of DAPT resulted in favorable ischemic outcomes comparable to the standard 12 months of DAPT for complex PCIs.

Why This Matters

  • It remains uncertain whether P2Y12 monotherapy, especially clopidogrel, following short-term DAPT is associated with favorable outcomes in patients with complex PCI.
  • This post-hoc analysis of SMART-CHOICE trial investigated the efficacy and safety of P2Y12 inhibitor monotherapy, mostly clopidogrel (78%), following short-term DAPT vs 12 months of DAPT in complex PCI.

Study Design

  • This was a post-hoc analysis of the SMART-CHOICE trial (NCT02079194), a multicenter, prospective open-label randomized clinical trial:
    • Patients were allocated to two groups before PCI: (1) DAPT (aspirin + P2Y12 inhibitor) for 3 months, followed by 9 months of P2Y12 inhibitor monotherapy (2) DAPT for 12 months
  • Complex PCI was defined by at least one of the following features:
    • 3 vessels treated, ≥3 stents implanted, ≥3 lesions treated, bifurcation PCI with ≥2 stents implanted, and a total stent length of ≥60 mm
  • Primary efficacy endpoint included major adverse cardiac and cerebrovascular event (MACCE), defined as the composite of all-cause death, myocardial infarction, or stroke at 12 months after the index procedure.
  • Primary safety endpoint included bleeding defined as Bleeding Academic Research Consortium (BARC) types 2–5 at 12 months after the index procedure.

Key Results

  • A total of 2,993 patients at 33 hospitals were randomized including 498 treated with complex PCIs and 2,495 undergoing non-complex PCIs
    • 76.3% (380/498) underwent complex PCIs and 83.8% (1961/2495) non-complex PCIs were exposed to clopidogrel-based therapy
  • At 1 year, compared to the non-complex PCIs group, patients in the complex PCI group had higher rates of MACCE (4.0% versus 2.3%; hazard ratio [HR] = 1.74; 95% confidence interval [CI]: 1.05–2.89, P = 0.033), all-cause death (2.6% versus 1.0%, HR = 2.52, 95% CI: 1.30–4.90, P = 0.007), cardiac death (1.6% versus 0.6%, HR = 2.51, 95% CI: 1.08–5.88, P = 0.033), and stent thrombosis (0.6% versus 0.1%, HR = 7.53, 95% CI: 1.26–45.06, P = 0.027).BARC types 2–5 bleeding showed similar rates in both the groups (2.6% versus 2.6%, HR = 1.02; 95% CI: 0.56–1.86, P = 0.939).
  • Effects of DAPT and P2Y12 inhibitor monotherapy in the complex and non-complex PCI groups
    • In non-complex PCI
      • MACCE rates: P2Y12 monotherapy showed similar MACCE rates compared with the DAPT group (2.6% versus 2.1%; HR = 1.27; 95% CI: 0.76–2.14; P = 0.359)
      • Bleeding BARC type 2–5: Significantly lower in P2Y12 group than DAPT group (1.9% versus 3.3%; HR = 0.57; 95% CI: 0.34–0.96; P = 0.033)
    • In complex PCI
      • MACCE rates: Similar in both groups (3.8% versus 4.2%; HR = 0.92; 95% CI: 0.38–2.21; P = 0.853)
      • Bleeding BARC type 2–5: lower in P2Y12 monotherapy group than DAPT group without statistical significance (1.9% versus 3.4%; HR = 0.58; 95% CI: 0.19–1.77; P = 0.340)
  • The interaction was not statistically significant between complex and non-complex PCI groups with MACCE (Pinteraction = 0.483) and BARC bleeding types 2–5 (Pinteraction = 0.904).

Limitations

  • This study on complex PCI was not pre-specified in the protocol, and thus the findings must only be interpreted as hypothesis-generating.
  • Complexity of coronary anatomy and lesions were not reviewed by an angiographic core laboratory but were site-reported.
  • P2Y12 inhibitor monotherapy was associated with fewer bleeding events in complex PCI without statistical significance due to type II error associated with a small sample size.
  • These findings cannot be generalized to Western patients because all study participants were East Asians.

    Roh JW, Hahn JY, Oh JH, Chun WJ, Park YH, Jang WJ, et al. P2Y12 inhibitor monotherapy in complex percutaneous coronary intervention: A post-hoc analysis of SMART-CHOICE randomized clinical trial. Cardiol J. 2021. doi:10.5603/CJ.a2021.0101. Epub ahead of print. PMID: 34523115.

MAT-BH-2300025/v1/Jan2023