Double-Port Totally Endoscopic Mitral Valve Replacement Through a Prosthesis-Sized Working Incision with Posterior Subvalvular Preservation

Objective: To evaluate the feasibility and early outcomes of totally endoscopic non-robotic mitral valve replacement using a double-port DCT approach with posterior subvalvular preservation. Methods: In this single-center retrospective observational study, 76 consecutive patients underwent totally endoscopic non-robotic mitral valve replacement between November 2023 and December 2025. The DCT approach was defined by exclusive endoscopic visualization, no rib spreading, a camera port and prosthesis-sized working incision placed in the same intercostal space, and thoracoscopic intracardiac instrumentation. Posterior ventricular-annular continuity was preserved whenever feasible by posterior leaflet preservation, native chordal preservation, or artificial chordal reimplantation after leaflet resection. Outcomes were reported descriptively with 95% confidence intervals. Results: Mechanical prostheses were implanted in 46 patients (60.5%) and bioprostheses in 30 (39.5%). Mean skin incision length was 3.8 ± 0.5 cm. Mean cardiopulmonary bypass and aortic cross-clamp times were 148.3 ± 38.6 and 101.9 ± 32.0 minutes, respectively. There was 1 early non-cardiac death (1.3%; 95% CI, 0.03%-7.1%), no late death, and no mitral valve reoperation (0%; 95% CI, 0%-4.7%). No moderate or severe paravalvular regurgitation was observed during early echocardiographic follow-up. Mean follow-up was 9.7 ± 6.0 months. Freedom from prosthetic valve-related adverse events was 98.6% (95% CI, 90.6%-99.8%) at 6 months and 95.2% (95% CI, 80.1%-98.9%) at 12 months. The 24-month estimate was identical but was based on few patients at risk and should be interpreted cautiously. Conclusions: The double-port DCT approach was technically feasible and was associated with acceptable early clinical and echocardiographic outcomes. Because of the retrospective single-center design, small sample size, absence of a comparator group, and short follow-up, these findings should be interpreted as feasibility data rather than evidence of superiority.