Abstract 17347: Mechanical versus Bioprosthetic Mitral Valve Replacement: Analysis of Functional and Hemodynamic Data
Introduction: there is a paucity of functional and hemodynamic data comparing biological and mechanical prostheses following mitral valve replacement (MVR). The purpose of this study was to compare the hemodynamic performance and patient’s functional capacity following isolated MVR with either a mechanical or biological prosthesis.
Methods: we carried out an ambispective study on 280 patients who underwent isolated MVR, between 2008 and 2012. Echocardiography was performed preoperatively and postoperatively. A subset of 150 patients also underwent a six minute walking test (6-MWT) preoperatively and after surgery (median follow-up: 4.4 years).
Propensity score analysis identified a final cohort of 60 patients in each group (i.e. biological vs. mechanical prosthesis).
Results: compared to bioprostheses, patients with mechanical valve had higher indexed effective orifice area (IEOA) (1.31±0.3cm2/m2 vs. 1.14±0.2, p=0.002). Postoperatively systolic pulmonary arterial pressure (SPAP) decreased to an higher extent in the mechanical group (from 41±11 to 35±6 mmHg) compared to bioprostheses (from 37± 8 to 36±8mmHg, p=0.001).
After surgery, the six-minute walking distance was significantly higher in mechanical group, when compared to bioprostheses (311±76m vs. 257±50m, p=0.0001).
Furthermore, the postoperative improvement of 6-MWT, in term of relative change, was significantly higher in patients with mechanical valves, as compared to biological prostheses (+72% vs. +16 %, p=0.0001, respectively).
In multivariate analysis, prosthesis type was an independent determinant of postoperative 6-MWT.
Conclusions: biological prostheses seem to be associated with a poorer hemodynamic and functional capacity than mechanical valves, after isolated MVR. Further larger studies are needed to confirm these results.
Author Disclosures: C. Fino: None. D. Cugola: None. P. Ferrero: None. A. Iacovoni: None. M. Merlo: None. E. Delia: None. L. Galletti: None. M. Caputo: None. L. Mantovani: None. J. Magne: None.
- © 2014 by American Heart Association, Inc.