Abstract 4135327: Long-term Bleeding Events after Percutaneous Coronary Intervention in Patients with Malignancy with and without Anticoagulant Therapy

Background: With the aging population, the prevalence of malignancies in patients undergoing percutaneous coronary intervention (PCI) is increasing. Active malignancy is increasingly recognized as a significant contributor to high bleeding risks. In cases where anticoagulant (AC) therapy is required, it becomes crucial to determine which is the optimal choice for cancer patients, direct oral anticoagulants (DOACs) or warfarin. The aim of this study was to investigate long-term bleeding events in patients with malignancy undergoing PCI. Methods: CLIDAS (Clinical Deep Data Accumulation System) is a multicenter database with 7 tertiary medical hospitals in Japan. This retrospective analysis using CLIDAS database included 6838 patients who underwent PCI during April 2014 and March 2020 and also who have completed 3-year follow-up were divided into two groups; No malignancy group (n=6155) and malignancy group (n=683). Malignancy was defined as patients with treatment history of malignancy. Furthermore, these patients were categorized into six groups based on the presence of malignancy and the type of AC therapy; 1) No malignancy without AC (n=5369), 2) No malignancy with DOAC (n=294), 3) No malignancy with warfarin (n=492), 4) Malignancy without AC (n=586), 5) Malignancy with DOAC (n=44), and 6) Malignancy with warfarin (n=53). The primary outcome was the incidence of bleeding events, defined according to the Global Use of Streptokinase and t-PA for Occluded Coronary Arteries classification of moderate and severe bleeding. Results: During the 3-year follow-up period, 260 (3.8%) patients experienced major bleeding events after PCI. Among these patients, 180 (3.4%) were in group 1, 9 (3.1%) in group 2, 33 (6.7%) in group 3, 27 (4.6%) in group 4, 2 (4.5%) in group 5, and 9 (17.0%) in group 6. Multivariate Cox regression analysis showed that patients in the malignancy group had a significantly higher rate of bleeding events (HR, 1.50; 95% CI, 1.03-2.18). Furthermore, only the malignancy with warfarin group showed a significantly higher rate of bleeding events compared to the no malignancy without AC group (HR, 4.03; 95% CI, 1.94-8.37). Conclusions: Patients with malignancies receiving warfarin were associated with a higher risk of bleeding events. DOACs may be a safer alternative to warfarin in reducing bleeding risk in this population.