Repair or replace for severe ischemic mitral regurgitation: prospective randomized multicenter data

Papillary muscle intervention vs mitral ring annuloplasty in ischemic mitral regurgitation

Background and Aims

The main pathophysiological factor of chronic ischemic mitral regurgitation (MR) is the outward displacement of the papillary muscles (PMs) leading to leaflet tethering. For this reason, papillary muscle intervention (PMI) in combination with mitral ring annuloplasty (MRA) has recently been introduced into clinical practice to correct this displacement, and to reduce the recurrence of regurgitation.

Methods

A meta‐analysis was conducted comparing the outcomes of PMI and MRA performed in combination vs MRA performed alone, in terms of MR recurrence and left ventricular reverse remodeling (LVRR). A meta‐regression was carried out to investigate the impact of the type of PMI procedure on the outcomes.

Results

MR recurrence in patients undergoing both PMI and MRA was lower than in those who only had MRA (log incidence rate ratio, −0.66; lower‐upper limits, −1.13 to 0.20; I² = 0.0%; p = .44; Egger's test: intercept 0.35 [−0.78 to 1.51]; p = .42).

The group with both PMI and MRA and that with only MRA showed a slightly higher reduction in left ventricular diameters (−5.94%; −8.75% to 3.13%,). However, in both groups, LVRR was <10%. No difference was detected between PM relocation/repositioning and papillary muscle approximation in terms of LVRR (p = .33).

Conclusions

Using PMI and MRA together has a lower MR recurrence than using MRA alone. No significant LVRR was observed between the two groups nor between the PMI techniques employed.

Systolic characteristics and dynamic changes of the mitral valve in different grades of ischemic mitral regurgitation - insights from 3D transesophageal echocardiography

BACKGROUND

Mitral regurgitation in ischemic heart disease (IMR) is a strong predictor of outcome but until now, pathophysiology is not sufficiently understood and treatment is not satisfying. We aimed to systematically evaluate structural and functional mitral valve leaflet and annular characteristics in patients with IMR to determine the differences in geometric and dynamic changes of the MV between significant and mild IMR.

METHODS

Thirty-seven patients with IMR (18 mild (m)MR, 19 significant (moderate+severe) (s)MR) and 33 controls underwent TEE. 3D volumes were analyzed using 3D feature-tracking software.

RESULTS

All IMR patients showed a loss of mitral annular motility and non-planarity, whereas mitral annulus dilation and leaflet enlargement occurred in sMR only. Active-posterior-leaflet-area decreased in early systole in all three groups accompanied by an increase in active-anterior-leaflet-area in early systole in controls and mMR but only in late systole in sMR.

CONCLUSIONS

In addition to a significant enlargement and loss in motility of the MV annulus, patients with significant IMR showed a spatio-temporal alteration of the mitral valve coaptation line due to a delayed increase in active-anterior-leaflet-area. This abnormality is likely to contribute to IMR severity and is worth the evaluation of becoming a parameter for clinical decision-making. Further, addressing the leaflets aiming to increase the active leaflet-area is a promising therapeutic approach for significant IMR. Additional studies with a larger sample size and post-operative assessment are warranted to further validate our findings and help understand the dynamics of the mitral valve.