Abstract 16721: Mechanical versus Biological Prostheses for Chronic Ischaemic Mitral Regurgitation: A Long-Term Hemodynamic and Functional Capacity Comparison
Introduction: mitral valve replacement (MVR) with chordal-sparing represents a valuable alternative surgical option for the treatment of chronic ischaemic mitral regurgitation (CIMR). However, the long-term hemodynamic performance and functional capacity of biological versus mechanical prostheses in patients treated for CIMR is still unknown.The purpose of this study was to compare, in patients undergoing MVR and coronary revascularization, the hemodynamics and functional capacity between the two types of prostheses, using exercise stress echocardiography and six-minute walking test (6-MWT).
Methods: we analyzed 86 consecutive patients who received MVR with either biological (n=41) or mechanical (n=45) prostheses, for CIMR. All patients underwent both preoperative and postoperative (at 32±13 months) resting and exercise stress echocardiography and 6-MWT. The mean age was 63.5±3.8 years. There was no significant difference between the 2 groups regarding baseline demographic, clinical and echocardiographic data.
Results: compared to biological prostheses, the postoperative indexed effective orifice area were significantly higher at rest and during exercise in patients with mechanical prostheses (rest: 1.3±0.2 vs. 1.19±0.3cm2/m2; p=0.03; exercise: 1.57±0.2 vs. 1.18±0.3cm2/m2 respectively; p=0.0001). The exercise systolic pulmonary arterial pressure was higher in biological prostheses, as compared to mechanical valves (59±7 vs. 41±5mmHg, p=0.0001). Compared to preoperative data, postoperative 6-MWT, adjusted for age and sex, significantly increased only in patients with mechanical valves (from 242±43 to 290±50m vs. 250±40 to 220± 44m, p= 0.001).
In multivariate analysis, after adjusting for age and sex, exercise indexed effective orifice area and exercise systolic pulmonary arterial pressure were identified as independent determinants of both postoperative functional capacity and postoperative improvement in functional capacity.
Conclusions: in patients with CIMR undergoing MVR, biological prostheses showed worse valve hemodynamic performance and reduced functional capacity, as compared to mechanical prostheses.
Author Disclosures: C. Fino: None. P. Ferrero: None. A. Iacovoni: None. E. Delia: None. M. Merlo: None. L. Galletti: None. M. Caputo: None. M. Senni: None. J. Magne: None.
- © 2014 by American Heart Association, Inc.