Survival and Cost Analysis of Surgical Mitral Valve Replacement With Different Prostheses: A Nationwide Cohort Study in Taiwan

BACKGROUND The choice of prosthetic valve for surgical mitral valve replacement (SMVR) remains a clinical challenge, particularly in balancing long-term survival with anticoagulation risk and prosthesis durability. In Taiwan, newer-generation tissue valves were introduced in recent years, providing additional options for patients and clinicians. MATERIAL AND METHODS We conducted a nationwide, retrospective cohort study using Taiwan's National Health Insurance Research Database from 2000 to 2017. Adult patients who underwent SMVR were categorized based on the prosthesis type: mechanical valve (MV), porcine bioprosthetic valve (PV), or newer-generation durable-tissue valve (DV). Propensity-score matching (PSM) was applied to minimize baseline differences. Outcomes analyzed included all-cause mortality, index hospitalization cost, length of hospital stay, and re-operation rates within 3 years. RESULTS Among 10 406 patients (5301 MV, 4300 PV, 805 DV), the DV group was older than in the MV group but younger and healthier than in the PV group. After PSM, DV was associated with significantly lower all-cause mortality compared to PV (HR: 0.61; 95% CI: 0.50-0.74; P<0.001) and MV (HR: 0.72; 95% CI: 0.60-0.88; P=0.002). Hospitalization costs and length of stay were highest for PV, moderate for DV, and lowest for MV. Within 3 years, DV showed the lowest re-operation rate (0.75%) compared to MV (1.96%; OR: 2.66, 95% CI: 1.17-6.09) and PV (3.21%; OR: 4.42, 95% CI: 1.94-10.03). CONCLUSIONS In this retrospective cohort, newer durable-tissue valves were associated with favorable early survival, lower short-term re-operation rates, and moderate hospitalization costs compared to older prostheses. However, the limited follow-up, potential confounding, heterogeneity of valve models, and era-related improvements in care preclude definitive conclusions about long-term durability or superiority. These real-world findings highlight the need for individualized prosthesis selection and longer-term prospective studies to confirm these observations.