Purpose <p>Severe mitral annular calcification (MAC) increases the complexity and risk of conventional mitral valve replacement (MVR) for patients with mitral stenosis (MS) and/or regurgitation (MR). In patients with severe concentric MAC who were not candidates for a traditional surgical approach, trans-atrial transcatheter MVR (TMVR) using a balloon-expandable transcatheter aortic valve (TAVR) is an alternative. We report our experience using this technique through a minimally invasive approach.</p> Methods <p>From April 2017 to September 2024, twenty-five symptomatic patients with severe MS and/or MR and MAC underwent minimally invasive trans-atrial TMVR with a TAVR valve at our institution. All patients had severe concentric MAC and were deemed ineligible for conventional MVR.</p> Results <p>Mean age of the patients was 74.6 ± 10.9 years and 84% (21/25) were female. Mean STS (Society of Thoracic Surgery) risk score for mortality was 9.1% ± 4.8%. Operative indication was severe MS in 11 patients (44%), severe MR in 4 (16%) and mixed MS/MR in 10 (40%). Surgical approach was via right anterior mini-thoracotomy (<i>n</i>=21) or robotic (<i>n</i>=4). Five patients had prior open cardiac surgery, and 6 had prior TAVR. Six patients (24%) were under cold fibrillatory arrest. Complications included paravalvular leak requiring re-intervention (<i>n</i>=1), left ventricular outflow tract obstruction (<i>n</i>=1) and atrio-ventricular groove disruption (<i>n</i>=1). There were no perioperative strokes. Average hospital length-of-stay was 7 days (IQR 6–13). Operative mortality was 16% (4/25), 76.0% (19/25) of patients survived discharge, and 1-year survival was 64.0% (16/25).</p> Conclusion <p>Minimally invasive trans-atrial TMVR using a TAVR valve provides a viable alternative therapy for patients with severe MAC who are not candidates for conventional MVR.</p> Graphical Abstract <p>Institutional Experience with direct trans-atrial TMVR using minimally invasive technique</p> <p></p>