Impact of surgical technique on postoperative ventricular arrhythmias in arrhythmic mitral valve prolapse

Abstract Background Mitral valve prolapse (MVP) is associated with progressive mitral regurgitation (MR) requiring surgical correction. A subset of patients with MVP may also constitute an "arrhythmic" phenotype suffering from malignant ventricular arrhythmias (VAs). Purpose To assess the impact of surgical technique for correction of degenerative MR including repair using artificial chords, repair with resection and mitral valve replacement (MVR) on longitudinal risk of VAs in patients with arrhythmic MVP. Methods Patients who had undergone mitral valve surgery for MVP with moderate to severe degenerative MR between 2010-2022 at a university hospital in Sweden were retrospectively included. Patients with ischemic heart disease, primary cardiomyopathy, channelopathy, or endocarditis were excluded. To examine changes in VAs (defined as sustained- or non-sustained ventricular tachycardias) as assessed by continuous Holter monitoring before and after surgery, generalized estimating equation (GEE) models were performed to account for the correlations between repeated monitoring in each patient and for differences in the time of measurement. Results Of 599 patients undergoing mitral valve surgery, 423 (71%) underwent repair using artificial chords, 62 (10%) repair with resection and 114 (19%) MVR. For those presenting with symptoms such as palpitations, presyncope, and/or syncope, Holter monitoring was conducted before (n=171; 29%) and/or after mitral valve surgery (n=184; 31%) (Figure 1). The distribution of VAs before and after surgery, stratified by surgical technique, is illustrated in Figure 2. In GEE models, repair using artificial chords was associated with increased postoperative VAs compared with the other surgical techniques (OR 2.14; 95% CI 1.19-3.83; p=0.01), repair with resection with reduced postoperative VAs compared with the other surgical techniques (OR 0.15; 95% CI 0.04-0.61; p=0.01), and no change in postoperative VAs was observed for MVR compared with the other surgical techniques (OR 0.724; 95% CI 0.39-1.35; p=0.31). The results remained similar after adjustment for age, sex, myxomatous disease/fibroelastic deficiency or bileaflet prolapse. Conclusion In patients with symptoms of palpitations, presyncope and/or syncope before or after mitral valve surgery, repair using artificial chords was associated with an increased risk of postoperative VAs. Prospective studies including continuous monitoring before and after surgery are needed to confirm these findings.