Real-World Evaluation of a Nationally Mandated Risk Stratification Tool for Destination Therapy LVAD in Japan.
BACKGROUND Patient selection for destination therapy (DT) with durable left ventricular assist devices (LVADs) remains a major challenge in Asian advanced heart failure practice. In Japan, the J-MACS score is mandatorily calculated before DT implantation and directly influences eligibility decisions; however, its real-world prognostic performance in DT recipients remains unclear. OBJECTIVES To externally validate the predictability of the J-MACS score on mortality in a nationwide Japanese DT cohort. METHODS We conducted a nationwide registry-based analysis of patients undergoing HeartMate 3 implantation as DT between May 2021 and October 2025. The primary endpoint was 2-year all-cause mortality. Prognostic performance of the J-MACS score-based on age, prior cardiac surgery, serum creatinine, and central venous pressure-to-pulmonary artery wedge pressure ratio-was evaluated using multivariable Cox models and restricted mean survival time. RESULTS In total, 210 patients (median age, 60 years; 159 [76%] male) were followed for a median of 514 days (IQR: 257-730 days) after LVAD implantation. The J-MACS score independently predicted mortality (adjusted hazard ratio: 1.17, 95% CI: 1.02-1.36, P = 0.037). The 2-year cumulative mortality rates were 5.8% (95% CI: 2.0%-16.1%) in the low-risk group, 12.7% (95% CI 6.3%-24.6%) in the intermediate-risk group, and 28.6% (95% CI 14.6%-51.2%) in the high-risk group (P = 0.003 for comparison). The high-risk group had approximately 4 months shorter survival. CONCLUSIONS This nationwide real-world study provides the first validation of a nationally mandated DT eligibility algorithm. The J-MACS score may support risk-based clinical decision-making in Japanese DT practice.