Abstract 16919: RV Dilation and Geometric Remodeling Impact Mortality in Cardiac Resynchronization Therapy
Introduction: The prognostic significance and reversibility of right ventricular (RV) dysfunction in patients undergoing cardiac resynchronization therapy (CRT) is unknown.
Methods: 332 consecutive patients (baseline characteristics, Table 1) undergoing CRT were prospectively studied. All-cause mortality was assessed at 2 years. RV dilation was defined as baseline RV end-diastolic dimension (RVEDd) ≥42mm. Left ventricular (LV) response (increase in LVEF ≥10% and decrease in LV diameter at end diastole ≥10%) and RV response (RVEDd <42mm in patients with baseline RV dilation) were defined at 6 months.
Results: Baseline RV dilation was associated with increased all-cause mortality (Figure, Panel A) even after adjustment for LV response (p=0.008). Amongst patients with baseline RV dilation, only pre-CRT chronic RV pacing was predictive of absent RV response (p=0.01). RV response, present in 55% of patients, was associated with greater reduction in estimated pulmonary artery systolic pressure (-10±2 vs. -2±1 mmHg, p=0.001) and reduced tricuspid regurgitation (p=0.003). The absence of RV response was associated with increased all-cause mortality when compared to both patients without RV dilation and those with RV dilation and RV response (Figure, Panel B). Amongst patients with RV dilation, the lack of RV response was associated with increased all-cause mortality even following adjustment for LV response (p=0.045).
Conclusion: In patients undergoing CRT, the presence of RV dilation and lack of RV response were associated with increased all-cause mortality, independent of LV remodeling. Chronic RV pacing was associated with lack of RV response.
- © 2012 by American Heart Association, Inc.