title: Impact of mitral regurgitation on reverse remodeling and outcome in patients undergoing cardiac resynchronization therapy.
abstract: BACKGROUND
  Mitral regurgitation (MR) is associated with reduced survival in patients with chronic heart failure, but may be improved with cardiac resynchronization therapy (CRT). We sought to evaluate the relationship between serial measurements of functional MR and reverse remodeling and outcomes in patients undergoing CRT.
  
  
  RESULTS
  A total of 266 consecutive patients undergoing CRT with available baseline echocardiograms and subsequent clinical and echocardiographic follow-up were included in the analysis. Long-term follow-up included all-cause mortality, heart transplantation, and implantation of a left ventricular (LV) assist device. Temporal changes in MR severity and LV end-systolic volume index (LVESVi) were evaluated by linear mixed-model analysis. CRT led to an immediate sustained decrease in MR (P<0.0001), with no significant subsequent change. The amount of MR decrease correlated with a greater decrease in LVESVi late (P≤0.0001), but not early (P=0.14), after CRT began. Patients with severe MR before CRT experienced a larger LVESVi decrease (P=0.005). Although baseline MR severity was not associated with adverse events (P=0.13), a larger MR decrease (P=0.001) and a smaller residual MR after the initial 6 months of CRT (P=0.03) were predictive of better outcome in a multivariable model.
  
  
  CONCLUSIONS
  Early reversal of functional MR was associated with reverse cardiac remodeling and improved outcomes. Patients with moderately severe to severe MR before CRT experienced relatively more reverse remodeling than patients with lesser degrees of MR.
authors: Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, OH 44195, USA.
authors: David
authors: D
authors: Verhaert
authors: Zoran B
authors: ZB
authors: Popović
authors: Sabe
authors: S
authors: De
authors: Chirapa
authors: C
authors: Puntawangkoon
authors: Kathy
authors: K
authors: Wolski
authors: Bruce L
authors: BL
authors: Wilkoff
authors: Randall C
authors: RC
authors: Starling
authors: W H Wilson
authors: WH
authors: Tang
authors: James D
authors: JD
authors: Thomas
authors: Brian P
authors: BP
authors: Griffin
authors: Richard A
authors: RA
authors: Grimm
mesh_terms: D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D058409:Cardiac Resynchronization Therapy Devices; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000150:complications* / Q000000981:diagnostic imaging* / Q000628:therapy; D015588:Observer Variation; D012720:Severity of Illness Index; D016019:Survival Analysis; D016896:Treatment Outcome; D014463:Ultrasonography; D020257:Ventricular Remodeling