Abstract 2143: Evolution of Intra-Ventricular Dyssychrony Over Time is Related to Progressive Remodeling in Patients with Left Ventricular Dysfunction
Background: Intra-ventricular dysynchrony (IVD) has important implications for pts with LV dysfunction but the relevance of changes in IVD to clinical course is unclear. We therefore investigated if serial changes in IVD are associated with ventricular remodeling.
Methods: We studied 72 pts (age 59±12 years, 67% men, LVEF 46±15%, QRS duration 96±23msec, 31% heart failure) who underwent baseline and follow-up (median 15 months) echo with color tissue Doppler imaging. The interval between QRS onset and maximal systolic velocity was measured from myocardial velocity curves in 6 standard basal segments, and standard deviation (TsSD) was used as a measure of IVD.
Results: Baseline TsSD was 35±20msec with 40 (56%) pts meeting the criterion for significant IVD. Remodeling (increase in end-systolic volume index [ESVI] during follow-up) occurred in 25 pts (35%). TsSD increased by 10±23msecs in pts with remodeling compared to a decrease of 8±19msec in pts without remodeling (p=0.001). There was a progressive increase in magnitude of remodeling according to increasing quartiles of change in TsSD (p=0.01). Change in TsSD over time (r=0.43, p<0.01) but not baseline TsSD correlated with change in ESVI (Figure⇓). NYHA class, wall motion score at dobutamine stress and change in TsSD over time were univariate predictors of change in ESVI but change in TsSD was the only independent predictor (p=0.001). Drug therapy status (beta-blockers/angiotensin converting enzyme inhibitors/ nitrates) did not predict remodeling.
Conclusion: An increase in IVD over time is associated with remodeling in pts with LV dysfunction. The role of IVD in progression of ventricular disease should be explored further.