Minimal Learning Curve for Minimally Invasive Aortic Valve Replacement

Abstract

Background: Minimally invasive aortic valve replacement (MiAVR) is an established technique for surgical aortic valve replacement (AVR). Although MiAVR was first described in 1993 and has shown good results compared to full sternotomy AVR (FSAVR) only a minority of patients undergo MiAVR. We recently started using MiAVR via an upper hemisternotomy. We aimed to examine the early results of our initial experience with this technique. Methods: We compared 55 MiAVR to a historical cohort of 142 isolated FSAVR (12.2016-12.2022). The primary outcome was in-hospital mortality. Secondary outcomes included cardiopulmonary bypass (CPB) and cross clamp times, blood product intake, in hospital morbidity, and length of ICU and hospital stay. Results: There was no significant difference in preoperative characteristics, including age, laboratory values and co-morbidities. There was no significant difference between the groups regarding in-hospital mortality (FSAVR 3.52% vs MiAVR 1.82%). There was no significant difference in CPB time (FSAVR 103.5 min [IQR 82-119.5] vs MiAVR 107 min [92.5-120]), aortic cross-clamp time (FSAVR 81 min [66-92] vs MiAVR 90 min [73-99]), and valve size (FSAVR 23 [21-25] vs MiAVR 23 [21-25]). The incidence of intraoperative blood products transfusion was significantly lower in the MiAVR group (10.91%) compared to the FSAVR group (25.35%, P=0.03). Conclusions: Our findings further establish the possibility of reducing invasiveness of AVR without compromising patient safety and clinical outcomes. This is true even in the learning curve period and without requiring any significant change in the operative technique and dedicated equipment.