Systolic Papillary Muscle Dyssynchrony Predicts Recurrence of Mitral Regurgitation in Patients with Ischemic Cardiomyopathy (ICM) Undergoing Mitral Valve Repair

Objective: We investigated the impact of papillary muscle dyssynchrony (DYS‐PAP) in predicting recurrent mitral regurgitation (MR) in patients with ischemic cardiomyopathy (ICM) undergoing undersized mitral ring annuloplasty (UMRA). Methods: One hundred forty‐four ICM patients (left ventricular ejection fraction <35%) in sinus rhythm undergoing UMRA between January 2001 and December 2010 at three Institutions (University Hospital, Maastricht, The Netherlands; Careggi Hospital, Florence, Italy; Civic Hospital, Brescia, Italy) were recruited. The primary endpoint was the recurrence of MR at the latest echocardiographic study defined as insufficiency ≥2+ in patients with no/trivial MR at discharge. The assessment of DYS‐PAP was performed by applying two‐dimensional (2D) speckle‐tracking imaging. Results: In patients with MR recurrence, DYS‐PAP significantly worsened (84.1 ± 8.8 msec vs.65.4 ± 8.8 msec at baseline, P < 0.001) whereas in patients with no MR recurrence, DYS‐PAP did not vary (22.3 ± 5.3 msec vs. 25.9 ± 7.2 msec at baseline, P = 0.8). Recurrent MR was positively correlated with preoperative DYS‐PAP (P < 0.001), baseline anterior mitral leaflet tethering angle α (P < 0.001) and tethering symmetry index α/β before surgery (P < 0.001). There was no significant correlation between MR recurrence and other echocardiographic parameters. Logistic regression analysis revealed that baseline values of DYS‐PAP (OR: 5.4 [95% CI: 3.1–7.7], P < 0.001), α (OR: 5.0 [2.6–6.7], P < 0.001), and α/β (OR: 3.9 [2.5–5.7], p < 0.001) were predictors of recurrent MR. A DYS‐PAP value ≥ 58 msec predicted recurrence of MR with 100% sensitivity and 83% specificity (area under the curve [AUC]: 0.92 [0.7–1], P < 0.001). Conclusions: A DYS‐PAP cutoff value of 58 msec is useful to identify patients in whom UMRA is likely to fail. That way decision making in ischemic functional MR might be facilitated.

Impact of preoperative anterior leaflet tethering on the recurrence of ischemic mitral regurgitation and the lack of left ventricular reverse remodeling after restrictive annuloplasty

BACKGROUND

The aim of this multicenter study was to investigate the impact of the preoperative anterior mitral leaflet tethering angle, α', on the recurrence of mitral regurgitation (MR) and left ventricular (LV) reverse remodeling (LVRR) after undersized mitral ring annuloplasty.

METHODS

The study population consisted of 362 patients, who were divided into two groups by baseline α': group 1, α' < 39.5° (n = 196), and group 2, α' ≥ 39.5° (n = 166). End points were recurrent MR ≥ 2+; LVRR, defined as a reduction in end-systolic volume index > 15%; and LV geometric reverse remodeling, defined as a reduction in systolic sphericity index to a normal value of <0.72 in patients with altered baseline geometry.

RESULTS

MR occurred in 9.6% (n = 19) and 43.3% (n = 72) of the patients in groups 1 and 2, respectively (P < .001). LVRR (85.7% vs 22.2%) at follow-up was higher in group 1 (P < .001). On multivariate regression analysis, α' ≥ 39.5° was a strong predictor of MR recurrence, lack of LV reverse remodeling and lack of LV geometric reverse remodeling (all P values < .001). In contrast, the posterior mitral leaflet tethering angle, β', was not significant (all P values > .05). When we allowed for interactions between α' and other risk factors, this effect occurred also in low-risk subgroups, and it was equivalent or generally attenuated in higher risk patients. There were no significant interactions between α' and any of the covariates (all P values > .05).

CONCLUSIONS

Anterior mitral leaflet tethering is a powerful predictor of MR recurrence and lack of LVRR after undersized mitral ring annuloplasty. Evaluation of leaflet tethering should be incorporated into clinical risk assessment and prediction models.