Clinical Outcomes After Durable Mitral Valve Repair for Ischemic Mitral Regurgitation.

BACKGROUND

This study aimed to clarify the incidence and determinants of postoperative adverse events in patients with ischemic cardiomyopathy who achieved long-term durable mitral valve repair.

METHODS

Between 1999 and 2015, 166 patients with chronic ischemic mitral regurgitation (MR) and a left ventricular ejection fraction ≤40% underwent restrictive mitral annuloplasty. During follow-up (65 ± 34 months), echocardiographic assessments were performed 809 times (mean, 4.9 ± 2.4 times), and 20 patients who had postoperative recurrent MR (moderate or severe) were excluded. Finally, 146 patients (aged 68 [63-75] years) whose MR was well controlled over time were included.

RESULTS

A total of 61 deaths or 27 readmissions for heart failure were observed in 76 patients (52%). Among hospital survivors, age (adjusted hazard ratio, 1.05; P = .001) and estimated glomerular filtration rate (adjusted hazard ratio, 0.61; P = .001) were identified as independent predictors of long-term mortality or readmission for heart failure. The degree of postoperative left ventricular function recovery was comparable between patients with and without adverse events. However, the former group showed greater values for systolic pulmonary artery pressure, tricuspid regurgitation severity, inferior vena cava dimension, and plasma brain natriuretic peptide level throughout the follow-up period (group effect P < .05 for all).

CONCLUSIONS

Approximately 50% of patients died or were hospitalized for heart failure even in the absence of recurrent MR during the 5-year follow-up, a finding indicating that durable mitral repair does not always lead to favorable clinical outcomes. The adverse events may have been related to volume overload secondary to impaired renal function and less favorable pulmonary hemodynamics.