Background: The aim of the study was to evaluate the long term results in patients with degenerative mitral valve bileaflet prolapse (DMVBLP) undergoing valve repair versus valve replacement comparing the consequences on survival related to each technique.
Methods: From 2001 to 2012, 421 patients underwent isolated primary operation for DMVBLP. Valve repair was performed in 146 patients (34.7%) (MVr group), and valve replacement (MVR) was performed in 275 (65.3%). MVR patients were divided in 2 subgroups: MVR subgroup A operated preserving the posterior subvalvular apparatus routinely and in selected cases the anterior or both (119 patients, 43.3%), and MVR subgroup B without preservation of the subvalvular apparatus (156 patients, 56.7%). Patients in the MVR group were older (70±12 years vs 56.4 ± 14.5) compared to those in the MVr group.
Results: In MVr group, 5 patients died (3.4%) and 6 patients (4.1%) underwent MVR due to MVr failure. 11 MVR patients were re-operated (4%). 11 patients died in subgroup A (9.2%); 29 patients died in subgroup B (18.6%). Patients in MVr group demonstrated significant LV end-diastolic diameter (LVEDD) and LV end-systolic diameter (LVESD) decrease postoperatively persistent during follow-up. LV mass also showed a significant regression during the first 4 years maintained during follow-up, while EF showed a trend to improve. In MVR subgroup A, LVEDD was initially decreased but increased during follow-up and LVESD remained high, resulting in a decreasing of EF. In MVR subgroup B, LVEDD and LVESD increased constantly resulting in a worsening of EF. Such data showed a statistical significance.
Conclusions: MVr in DMVBLP patients achieves better preservation of LV systolic indexes than MVR, due to preservation of the subvalvular apparatus and LV geometry and it guarantees better short and long term survival. Whenever MVr is unfeasible, we recommend subvalvular preservation when performing MVR, in order to decrease the risk of early and late mortality and to improve LV function.
