Impact of six versus 12 months of dual antiplatelet therapy in patients with drug-eluting stent implantation after risk stratification with the residual SYNTAX score: Results from a secondary analysis of the I-LOVE-IT 2 trial.

BACKGROUND: The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation remains undetermined, especially for those at high risk of cardiac events postprocedure.

OBJECTIVES: This study was aimed to investigate the impact of 6 versus 12 months of DAPT after DES implantation based on risk stratification with the residual SYNTAX score (rSS).

METHODS: A total of 2737 patients in the I-LOVE-IT 2 trial were grouped according to rSS status (low rSS [rSS = 0, n = 1474] versus high rSS [rSS > 0, n = 1263]) and DAPT duration (6 months vs. 12 months). The primary endpoint was 12-month target lesion failure (TLF), and the major secondary endpoints were 12-month net adverse clinical events (NACE) and major bleeding.

RESULTS: Incidences of TLF (5.2 vs. 7.4%, P = 0.01) and NACE (9.2 vs. 13.4%, P < 0.001) at 12 months were significantly higher in patients with high rSSs compared with patients with low rSSs. Landmark analysis showed that, in patients with high rSS, 12-month DAPT was associated with slightly lower risks of TLF (3.0% vs. 1.6%, P = 0.08) and NACE (7.0 vs. 4.4%, P = 0.054) compared with 6-month DAPT within 6 to 12 months after PCI. Patients with different DAPT durations had similar risks of bleeding both in the low and high rSS groups.

CONCLUSIONS: Patients with high rSSs have an increased risk of TLF and NACE at 12 months after DES implantation. Twelve-month DAPT might be superior to 6-month DAPT in patients with high rSS for reducing adverse events within 6 to 12 months after PCI without excessive risk of bleeding. © 2017 Wiley Periodicals, Inc.