Konno-Rastan aortic root enlargement for late tunnel-type subaortic stenosis: A case report

A 27-year-old woman with prior subaortic membrane resection presented with recurrent tunnel-type subaortic stenosis, severe aortic regurgitation, and a small annulus. She underwent a Konno–Rastan procedure with aortic root enlargement and mechanical valve implantation. Postoperative complete Atrioventricular (AV) block required pacemaker insertion. This rare adult case highlights the strategic use of preoperative indexed Effective Orifice Area (iEOA) calculations to guide surgical planning and avoid patient–prosthesis mismatch (PPM). Additionally, it underscores the feasibility and relevance of the Konno–Rastan technique in adult reoperations, contributing valuable insight into decision-making for anatomically complex Left Ventricular Outflow Tract (LVOT) pathologies.