Mid-term outcomes of robotic assisted versus conventional sternotomy for mitral valve replacement: a nationwide propensity-weighted analysis using Taiwan's National Health Insurance Research Database.

Abstract

Background: This study aimed to compare survival, complications, and healthcare costs between robotic-assisted and conventional sternotomy mitral valve replacement, using a nationwide population-based dataset from Taiwan.

Methods: Patients who underwent isolated surgical MVR between 2016 and 2021 were identified from Taiwan's National Health Insurance Research Database. A total of 5,736 patients met inclusion criteria: 5,547 underwent conventional sternotomy MVR (CSMVR), and 113 received robot-assisted MVR (RAMVR). To reduce confounding, inverse probability of treatment weighting (IPTW) was applied using age, sex, and Charlson Comorbidity Index as covariates, yielding a weighted cohort of 5,660 CSMVR and 5,640 RAMVR cases for outcome analysis.

Results: After IPTW adjustment, RAMVR was associated with significantly better survival (hazard ratio: 0.37; 95% confidence interval: 0.33-0.41; p < 0.01), shorter hospital stay (16.5 vs. 22.7 days, p < 0.01), and shorter intensive care unit stay (4.4 vs. 9.1 days, p < 0.01). RAMVR patients also had lower rates of dialysis and stroke. One-year post-discharge medical costs were significantly lower in the RAMVR group (USD 1,640 vs. 4,003, p < 0.01). Although inpatient costs appeared lower for RAMVR, this reflects the exclusion of patient-borne expenses for robotic equipment not reimbursed by insurance.

Conclusion: In this national population-based analysis, RAMVR was associated with better mid-term survival, shorter hospital stays, and reduced medical costs compared with conventional sternotomy. These findings support the use of robotic-assisted surgery as a safe and effective alternative in selected patients undergoing mitral valve replacement.