Diastolic Function and Left Atrial Remodeling after Mitral Valve Repair with Additional Papillary Muscle Repositioning for Type IIIb Secondary Mitral Regurgitation

Background: Previous studies have shown that mitral annuloplasty with additional papillary muscle repositioning (PMR) may improve durability of mitral valve repair (MVR) in type IIIb secondary mitral regurgitation (SMR). PMR is intended to restore mitral valve geometry, but might also negatively affect diastolic function. In this comparative study, diastolic function and left atrial remodeling were assessed, in patients receiving isolated annuloplasty versus with additional PMR.

Method: In this study, 103 consecutive type IIIb SMR patients were included, from which 51 underwent annuloplasty with additional PMR (study group), and 52 underwent isolated annuloplasty (control group). Echocardiographic parameters including diastolic functional parameters, such as mitral E/A ratio (mitral E-wave velocity divided by mitral A-wave velocity), mitral E/e´ ratio (mitral E-wave velocity divided by mitral annular e´ velocity), and left atrial (LA) strain were analyzed up to 12 months of follow-up (12 mFU).

Results: Study and control groups were similar regarding baseline echo parameters. At 6 and 12 mFU, mean gradient after MVR showed no difference between groups. LA volumes revealed no significant differences between groups at FU (study vs. control: 99.4 ± 52.6 mL vs. 83.6 ± 51.7 mL, p = 0.230 in 6 mFU, 86.9 ± 38.0 mL vs. 80.2 ± 32.4 mL, p = 0.477 in 12 mFU). No significant changes were observed with respect to diastolic parameters (study vs. control): E/A ratio (2.3 ± 1.4 vs. 2.3 ± 1.5, p = 0.904 at 6 mFU, 2.9 ± 1.9 vs. 2.4 ± 2.4, p = 0.478 at 12 mFU) and E/e’ ratio (25.6 ± 9.8 vs. 23.9 ± 4.0, p = 0.494 at 6 mFU, 25.8 ± 9.2 vs. 22.7 ± 7.4, p = 0.201 at 12 mFU). Furthermore, LA strain remained similar in study and control groups after MVR (10.5 ± 8.0 vs. 14.0 ± 6.6, p = 0.098 at 6 mFU, 11.1 ± 6.4 vs. 11.7 ± 7.0, p = 0.708 at 12 mFU).

Conclusion: Addition of PMR does not negatively affect diastolic function compared with isolated mitral annuloplasty for type IIIb SMR in this echocardiographic analysis. In conjunction to previously demonstrated advantages regarding SMR recurrence, this finding further corroborates hemodynamic superiority of additional PMR compared with isolated annuloplasty.

Publication History

Article published online:
03 February 2022