Timing of surgery in patients with chronic, severe mitral regurgitation

Mitral regurgitation in patients with advanced systolic heart failure

BACKGROUND

Mitral regurgitation (MR) may develop in patients with advanced systolic congestive heart failure (CHF) without organic mitral valve disease and contribute to worsening symptoms and survival. Surgical mitral annuloplasty improves symptoms in patients with advanced CHF, and percutaneous approaches to mitral annuloplasty are being developed. Our objective was to define the prevalence, clinical correlates, and prognostic implications of functional MR and the use of mitral annuloplasty in patients with advanced systolic CHF evaluated in a heart failure clinic.

METHODS AND RESULTS

We reviewed clinical, echocardiographic, and survival data from all patients with advanced systolic CHF (New York Heart Association class III or IV; ejection fraction </=35%) resulting from ischemic or idiopathic cardiomyopathy who were evaluated at our heart failure clinic between January 1996 and September 2001. Of 716 patients with advanced CHF, 558 had satisfactory baseline echocardiograms performed at our institution. Among these patients, MR was severe in 24 (4.3%), moderate-severe in 70 (12.5%), moderate in 122 (21.9%), mild-moderate in 66 (11.8%), mild in 218 (39.1%), and absent or present as only a trace in 58 (10.4%). The severity of MR was confirmed by quantitative analysis in 72% of patients with hemodynamically significant MR (more than moderate). The severity of MR correlated with the severity of systolic dysfunction (P <.001), ventricular dilatation (P <.03), atrial dilatation (P <.001), diastolic dysfunction (P <.001), and pulmonary hypertension (P <.001). Coexistent severe or moderate-severe tricuspid regurgitation was present in 25% of patients with hemodynamically significant MR. Patients with hemodynamically significant MR had higher mortality (P=.03) but not when controlling for age, sex, cause, New York Heart Association class, and ejection fraction (P=.95). Only 3 patients subsequently underwent mitral valve repair.

CONCLUSION

Among patients with advanced CHF, hemodynamically significant MR is common. The severity of MR did not provide independent prognostic information in this group recognized to have uniformly high mortality.

Impact of a preoperative mitral regurgitation scoring system on outcome of surgical repair for mitral valve prolapse

The optimal timing of surgical correction of severe mitral regurgitation (MR) is important for improved morbidity and mortality. We utilized a scoring system to decide the timing of procedures. Based on clinical features and echocardiographic data, we hypothesized that preoperative semi-quantitation of MR using this scoring system may be useful for predicting prognosis after repair. The MR score was composed of 6 parameters associated with disease severity (i.e., history of heart failure, atrial fibrillation, pulmonary hypertension, left ventricular end-systolic dimension, fractional shortening, and left atrial dimension). The maximum score was 6. Of 267 patients who underwent mitral valve repair in the last 10 years, 191 patients with mitral valve prolapse were studied. Patients were categorized into 2 groups according to MR score (group low [L] : 0 to 2.5 and group high [H]: >/=3.0) irrespective of New York Heart Association functional class. A significant difference in postoperative event-free survival was observed between both groups (p = 0.0014); the adjusted risk ratio was 3.4 (95% confidence interval 1.6 to 7.2). Postoperative echocardiography showed larger left ventricular systolic dimensions (p <0.0001), lower fractional shortening (p = 0.0016), and larger left atrial dimensions (p <0.0001) in group H than group L. Thus, an MR score is a simple way to predict the prognosis of severe MR independently of subjective symptoms in patients undergoing mitral valve repair.