Objective: To assess the impact of dual antiplatelet (DAP) therapy of >12 months on long-term death and myocardial infarction (MI) after percutaneous coronary intervention (PCI).
Design, setting and patients: Prospective, single-centre, observational study of 1859 consecutive patients who underwent successful PCI of a native coronary artery and survived event-free for at least 12 months.
Main outcome measures: Combined end point of death or non-fatal MI determined by survival analysis and propensity-adjusted multivariable Cox regression. Similar analyses were performed in the two stent subsets: bare metal stents (n = 835), drug-eluting stents (n = 1024); and three high-risk subsets: diabetic patients (n = 486), patients presenting with MI (n = 713), and those with ACC/AHA type C lesions (n = 717).
Results: Baseline characteristics were as follows: mean (SD) age 64 (12) years, male 69%, diabetic 26%, presentation with MI 38%, mean (SD) ejection fraction 49 (12)%, mean (SD) vessel diameter 3.1 (0.5) mm. Duration of DAP was 27 (11) months in “DAP >12 months” and 4.1 (4.1) months in “DAP ⩽12 months” (p<0.001). At a median follow-up of 3.4 years after PCI, “DAP >12 months” vs “DAP ⩽12 months” had similar incidence of death or MI (9.4% vs 10.3%, log-rank p = 0.83). After multivariable adjustment, DAP therapy >12 months was not associated with lower incidence of death or MI than DAP therapy ⩽12 months (adjusted HR = 1.01; 95% CI 0.74 to 1.37, p = 0.95). Analysis of each of the five predefined subsets showed similar results.
Conclusions: In patients who undergo successful native coronary PCI and survive event-free for at least 12 months, continuation of dual antiplatelet therapy beyond 12 months does not confer long-term protection from death or MI.
Statistics from Altmetric.com
Funding This article was not funded by any external funding. The Guthrie PCI Registry is entirely funded by the Guthrie Health Foundation.
Competing interests None.
Ethics approval Approval from the institutional review board of the Guthrie Health Foundation.
Provenance and peer review Not commissioned; externally peer reviewed.