Mitral valve replacement or repair: choosing optimal surgical treatment of hypertrophic obstructive cardiomyopathy

Academician Ye. Meshalkin Novosibirsk Research Institute of Circulation Pathology, Ministry of Health Care of Russian Federation, 15 Rechkunovskaya St., 630055 Novosibirsk, Russian Federation Objective. The purpose of this study was to compare clinical and hemodynamic efficacy of different surgical approaches to correct outflow tract obstruction and mitral insufficiency in patients with hypertrophic cardiomyopathy. Methods. Over a period from November 2010 to August 2013,146 patients with hypertrophic obstructive cardiomyopathy (HOCM) underwent surgical treatment 88 patients met the inclusion criteria and were randomized in two groups: Group I - extended myomectomy and MV replacement; Group II -extended myomectomy and MV repair. Mean age in Group I and Group II was 51.4±14.4 and 47.9±14.1 years respectively (p = 0.262). Mean peak gradient in Group I and Group II was 89.9±27.2 mm Hg. and 96.6±28.1 mm Hg. (p = 0.168). Pronounced MR was observed in 24 (58.5%) and 23 (56.1%) cases, moderate one in 17 (41.5%) and 18 (43.9%) cases in Group I and Group II respectively (p = 0.823). All patients demonstrated SAM syndrome. Results. There was one (2.4%) early death in Group I (p = 0.314). In both groups such complications as AV block, ventricular septal defect and rupture of the left ventricle (p = 1.0) didn’t differ significantly. Average follow-up was 23.2 months for Group 1 and 25.8 months for Group 2. The survival rate in group I and group II was 78.9% and 96.6% respectively (Log-rank test = 0.034). Freedom from thromboembolic events was 83.2% and 100% respectively (Log-rank test = 0.026). Conclusion. MV replacement and MV repair during extended septal myomectomy in patients with HOCM can be an effective method to eliminate MR and outflow tract obstruction. MV repair in patients with HOCM reduces thromboembolic events and provides better mid-term survival.