Comparison of Direct Oral Anticoagulants and Low-Molecular-Weight Heparins in Cancer Patients with Nonvalvular Atrial Fibrillation: Insights from a Single-Center Experience

BACKGROUND: Atrial fibrillation (AF) is frequently encountered in patients with cancer and poses challenges for anticoagulant management. The present study was conducted to compare clinical outcomes associated with direct oral anticoagulants (DOACs) and low-molecular-weight heparin (LMWH) in individuals with active malignancy and nonvalvular AF (NVAF). METHODS: Data from patients with active cancer who received LMWH or DOACs for NVAF were retrospectively screened. Efficacy, safety, and survival outcomes were analyzed. RESULTS: The study enrolled 222 patients, of whom 25.7% received LMWH and 74.3% received DOACs. Cancer stage, type, and treatment were comparable between groups. The DOAC group had higher CHA2DS2-VA (3.13 ± 1.21 vs. 2.42 ± 1.33; P < .001) and HAS-BLED scores (2.13 ± 0.83 vs. 1.84 ± 0.79; P = .022). The primary composite endpoint occurred more frequently in the LMWH group (17.5% vs. 12.1%; log-rank P = .036). Myocardial infarction was significantly higher in the LMWH group (8.8% vs. 1.8%; log-rank P = .003), while rates of ischemic stroke (3.5% vs. 6.7%; log-rank P = .927) and venous thromboembolism (5.3% vs. 4.8%; P = .537) were similar. Any bleeding (17.5% vs. 13.3%; log-rank P = .039) and major bleeding (7.0% vs. 1.8%; log-rank P = .010) were more frequent with LMWH, whereas clinically relevant non-major bleeding was comparable (10.5% vs. 11.5%; log-rank P = .359). All-cause mortality was significantly higher in the LMWH group (75.4% vs. 49.1%; log-rank P < .001), and LMWH use independently predicted mortality (hazard ratio = 2.14, P < .001, 95%CI: 1.45-3.17). CONCLUSION: Although unmeasured confounders such as drug adherence and selection bias cannot be excluded due to the retrospective design, DOACs appear to be more effective and safer than LMWH in cancer patients with AF.