title: Predictors of long-term outcomes in patients with significant myxomatous mitral regurgitation undergoing exercise echocardiography.
abstract: BACKGROUND
  Significant myxomatous mitral regurgitation leads to progressive left ventricular (LV) decline, resulting in congestive heart failure and death. Such patients benefit from mitral valve surgery. Exercise echocardiography aids in risk stratification and helps decide surgical timing. We sought to assess predictors of outcomes in such patients undergoing exercise echocardiography.
  
  
  RESULTS
  This is an observational study of 884 consecutive patients (age, 58 ± 14 years; 67% men) with grade III+ or greater myxomatous mitral regurgitation who underwent exercise echocardiography between January 2000 and December 2011 (excluding functional mitral regurgitation, prior valvular surgery, hypertrophic cardiomyopathy, rheumatic valvular disease, or greater than mild mitral stenosis). Clinical and echocardiographic data (mitral regurgitation, LV ejection fraction, LV dimensions, right ventricular systolic pressure) and exercise variables (metabolic equivalents, heart rate recovery at 1 minute after exercise) were recorded. Composite events of death, myocardial infarction, stroke, and progression to congestive heart failure were recorded. Mean LV ejection fraction, indexed LV end-systolic dimension, resting right ventricular systolic pressure, peak stress right ventricular systolic pressure, metabolic equivalents achieved, and heart rate recovery were 58 ± 5%, 1.6 ± 0.4 mm/m(2), 31 ± 12 mm Hg, 46 ± 17 mm Hg, 9.6 ± 3, and 33 ± 14 beats, respectively. During 6.4 ± 4 years of follow-up, there were 87 events. On stepwise multivariable Cox analysis, percent of age/sex-predicted metabolic equivalents (hazard ratio, 0.99; 95% confidence interval, 0.98-0.99; P=0.005), heart rate recovery (hazard ratio, 0.29; 95% confidence interval, 0.17-0.50; P<0.001), resting right ventricular systolic pressure (hazard ratio, 1.03; 95% confidence interval, 1.004-1.05; P=0.02), atrial fibrillation (hazard ratio, 1.91; 95% confidence interval, 1.07-3.41; P=0.03), and LV ejection fraction (hazard ratio, 0.96; 95% confidence interval, 0.92-0.99; P=0.04) predicted outcomes.
  
  
  CONCLUSIONS
  In patients with grade III+ or greater myxomatous mitral regurgitation undergoing exercise echocardiography, lower percent of age/sex-predicted metabolic equivalents, lower heart rate recovery, atrial fibrillation, lower LV ejection fraction, and high resting right ventricular systolic pressure predicted worse outcomes.
authors.affiliation: Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH.
authors.forename: Peyman
authors.initials: P
authors.lastname: Naji
authors.forename: Brian P
authors.initials: BP
authors.lastname: Griffin
authors.forename: Fadi
authors.initials: F
authors.lastname: Asfahan
authors.forename: Tyler
authors.initials: T
authors.lastname: Barr
authors.forename: L Leonardo
authors.initials: LL
authors.lastname: Rodriguez
authors.forename: Richard
authors.initials: R
authors.lastname: Grimm
authors.forename: Shikhar
authors.initials: S
authors.lastname: Agarwal
authors.forename: William J
authors.initials: WJ
authors.lastname: Stewart
authors.forename: Tomislav
authors.initials: T
authors.lastname: Mihaljevic
authors.forename: A Marc
authors.initials: AM
authors.lastname: Gillinov
authors.forename: Milind Y
authors.initials: MY
authors.lastname: Desai
mesh_terms: D000328:Adult; D004452:Echocardiography; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000401:mortality*; D008945:Mitral Valve Prolapse / Q000000981:diagnostic imaging* / Q000401:mortality*; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012307:Risk Factors; D012720:Severity of Illness Index; D013995:Time
keywords: echocardiography; exercise test; mitral valve insufficiency; outcome assessment (health care)