In-hospital outcomes and cost-effectiveness of transcatheter aortic valve replacement among younger patients: a double/debiased machine learning approach using electronic health records in Germany.

BACKGROUND

The prevalence of severe symptomatic aortic stenosis is increasing with population aging. Although surgical aortic valve replacement (SAVR) has traditionally been the standard treatment, transfemoral transcatheter aortic valve replacement (TF-TAVR) is increasingly used. The optimal treatment for patients aged 60-75 remains debated.

METHODS

This retrospective cohort study analyzed 28,805 German patients who underwent isolated SAVR or TF-TAVR (2018-2022). We applied double/debiased machine learning estimators that combined adaptive lasso variable selection with propensity score-based weighting across 21 baseline characteristics. Cost-effectiveness was assessed via incremental cost-effectiveness ratios (ICER) and cost-effectiveness acceptability curves from in-hospital and 1-year perspectives.

RESULTS

Compared with SAVR, TF-TAVR was associated with a significant reduction in in-hospital mortality (causal risk ratio [RR] 0.65; p = 0.012), along with lower rates of bleeding (RR 0.29; p < 0.001), postoperative delirium (RR 0.32; p < 0.001), and mechanical ventilation > 48 h (RR 0.39; p < 0.001). No significant difference was observed in acute kidney injury rates (RR 0.89; p = 0.150). However, reimbursement was substantially higher for TF-TAVR (€7071 more per case, p < 0.001). A hypothetical shift from SAVR to TF-TAVR was associated with an ICER of €857,413 (95% CI €472,195-€4,310,651) from the in-hospital perspective and €196,422 (95% CI €123,873-€457,813) from the 1-year perspective. Notably, unadjusted analyses indicated a narrowing cost gap over time: Reimbursement for TF-TAVR decreased by approximately 12% between 2018 and 2022, while SAVR costs remained stable. Consequently, TF-TAVR is becoming increasingly cost-effective.

CONCLUSION

Given an estimated life expectancy of 11 to 25 years in this population, the incremental costs per life saved associated with a hypothetical shift from SAVR to TF-TAVR appear justifiable. Nonetheless, individual patient circumstances must always be considered in decision-making.