Abstract 13695: Prevalence of Mechanical Dyssynchrony in Hypertrophic Cardiomyopathy
BACKGROUND. Dyssynchrony has been extensively studied in LV systolic dysfunction, properly selecting patients for CRT. The present study has the objective to analyze the prevalence of dyssynchrony in a hypertrophic cardiomyopathy (HCM) population and its correlation with left ventricular mass related measurements and diastolic function parameters by echocardiography.
METHODS/RESULTS. We included 160 patients, being 120 HCM patients and 40 controls. HCM patients had higher LV mass (286.6±106g vs 144±36g, p<0.001), septum thickness (2.0±0.5cm vs 0.9±0.1cm, p<0.001), and septum/posterior thickness ratio (1.8±0.4 vs 1.0±0.1, p<0.001). Resting LVOT gradient was 31±35mmHg in HCM patients. Derived from Doppler method, time delay (Δt) between 2 opposing walls and standard deviation of time to peak (SD) were taken from all 3 apical plane views (A4C, A2C and A3C) on basal and mid wall regions for systolic velocities (Sm) and systolic strain rate (sSR). Differences were found between all indexes originated from A4C and A3C views with higher values for HCM patients for Sm (A4C-ΔtSmMid: 41±27.3ms vs 59.6±53.7ms, p=0.009; A3C-ΔtSmBasal: 20.5±13.4ms vs 36.8±40.0ms, p=0.001; A3C-ΔtSmMid: 30.5±30.8ms vs 47.4±51.2ms, p=0.031) and for sSR (A4C-ΔtsSRBasal: 39.3±31.3ms vs 68.8±61.7ms, p = 0.001; A3C-ΔtsSRBasal: 30.0±37.6ms vs 59.3±58.1ms, p =0.002), this last variable only on the mid wall region. The SDSm index was also higher in HCM patients (25.0±11.6ms vs 31.2±20.0ms, p =0.021). Multivariate regression with all conventional systolic and diastolic echocardiography, A3C-ΔtSmBasal showed the most significant correlation with E/e’ (p=0.0004). No significant correlations were found with left ventricular mass variables.
CONCLUSION. An increased Δt between two opposing walls was found in HCM patients, mainly from apical 4 and 3 chamber plane views and they were significantly associated with the diastolic dysfunction.
- © 2011 by American Heart Association, Inc.