Clinical Outcomes of a Customized Mitral Valve Plasty for Functional Mitral Regurgitation with a Low Ejection Fraction and Implications for Preoperative Right Ventricular Function

Abstract

Purpose: To evaluate clinical outcomes of customized mitral valve plasty (MVP) for the treatment of functional mitral regurgitation (FMR) with a low ejection fraction (EF) and to determine which preoperative factors affected the clinical outcome. Methods and Results: MVP was adjusted according to the degree of left ventricle (LV) remodeling. We performed mitral annuloplasty (MAP) alone in 14 patients and added subvalvular procedures (SVPs) in 22 patients at a high risk of recurrent MR. During follow-up, reverse LV remodeling was obtained and the 3-year and 5-year non-recurrence rates of MR grade ≥2 were 94% and 89%, respectively. Two patients died during their hospital stay, and four more patients died of cardiac causes during follow-up. The 3-year and 5-year rates of freedom from cardiac-related mortality were 86% and 81%, respectively; no significant difference was observed between the two treatment groups. Right ventricular fractional area change (RVFAC) was a significant predictor of cardiac mortality. Patients with an RVFAC of <26% had significantly poorer cardiac-related mortality (71% at 3 years) than those with an RVFAC of ≥26% (95% at 3 years). Conclusion: Customized MVP provided durable mitral competence and reverse LV remodeling. Preoperative RV function was associated with cardiac-related mortality.

The Use of Subvalvular Repair for Functional Mitral Regurgitation

“…The results reported by Furukawa et al 1) seem to coincide with those reported by Kainuma et al 9) The evidence suggests that the patients with smaller ventricular chambers and improvement of LV remodeling have good results in the long run even with the use of RMA alone because the interpapillary muscle distance (IPMD) is reduced with favorable LV remodeling. Recently, the pivotal role of IPMD has been shown in a report from the Osaka Rosai Hospital.…”

“…Furukawa et al 1) revealed no difference in a 3-year rate of freedom from cardiac-related mortality when comparing the patients who received RMA alone to those who were managed with the combined RMA and SVR (93% vs 81%; P = 0.3). As highlighted in the results, although one patient who underwent an isolated RMA experienced recurrence of MR ≥2; however, LVDs significantly decreased (from 46 ± 8 to 37 ± 12 mm; P <0.01) and LVEF significantly improved (from 29 ± 7% to 46 ± 18%; P = 0.01).…”

“…In IMR, this geometric alteration should be considered in three dimensions: the anteroposterior diameter of the annulus, the tenting area, and the interpapillary muscle distance. 2 , 4 – 6) We use 4-0 Goretex sutures with pledgets for the types of PMs anatomically classified as I, II, and III and a 4-0 Goretex prosthesis for types IV and V. 4 – 6 , 8) Furukawa et al 1) reported 11 patients who underwent PMA but did not describe the anatomy of PMs. In addition, the authors used PMA with concurrent LVR by performing an approximation of the PM from the base to the center with two mattress sutures (3-0 polypropylene) and through the LV incision.…”

“… 2 , 3) Importantly, the authors assessed the right ventricular fractional area change (RVFAC) to establish if the RV function was associated with cardiac-related mortality. 1) …”

Exploring the Operative Strategy for Secondary Mitral Regurgitation: A Systematic Review

“…Resistance among surgeons to the use of subvalvular repair (SR) combined with RMA can be explained, at least in part, by the fact that clinical benefit of additional handling the subvalvular apparatus which has been reported in observational studies [6][7][8] has been confirmed in only a few randomized clinical trials [9,10]. Although these randomized studies have shown few rates of mitral regurgitation recurrence and reoperation with the combined procedure using surgery of papillary muscles (PMs), these trials were individually underpowered to detect differences in the frequency of clinical events.…”