Valve-in-valve TMVR showed 100% success in 33 patients with mitral bioprosthetic valve dysfunction.

This single-center retrospective cohort study included 33 patients with mitral bioprosthetic valve dysfunction following prior mitral valve replacement. The intervention was valve-in-valve transcatheter mitral valve replacement (TMVR), with the comparator being the status prior to the operation. Follow-up duration was not reported.

The primary outcome assessed clinical efficacy and follow-up results. TMVR success rate was 100.0%, with 33 of 33 procedures deemed successful. Secondary outcomes included NYHA grade, EQ-VAS score, and 6-minute walking distance. All three secondary outcomes improved significantly, with a P value less than 0.05 implied for each.

Safety analysis identified cerebral infarction as an adverse event. A serious adverse event of death occurred 7 days after the operation. Discontinuations and tolerability were not reported. The study was funded by sources not reported, and potential conflicts of interest were not reported.

Key limitations include the small sample size of 33 patients and the retrospective, single-center design. Because the study type is a retrospective cohort study, causal language should be avoided. The absence of reported follow-up duration and specific p-values for secondary outcomes limits the precision of the reported benefits. Clinicians should interpret these results with caution given the inherent uncertainties of early-phase, observational evidence.