Abstract 3072: Prevalence of Dyssynchrony in Obese Subjects With No Known Cardiac Disease Using Velocity Vector Imaging
Introduction: Obesity is a risk factor for heart failure. Obesity can lead to heart failure through multiple neurohormonal and mechanical pathophysiological mechanisms. Similar to other causes of heart failure, obesity could affect synchrony of left ventricular (LV) contractile function leading to heart failure. To-date there has been no data assessing intra LV dyssynchrony in obese subjects.
Aim: We examined the occurrence of intra LV dyssynchrony in obese versus non-obese subjects without any known cardiac disease, using velocity vector imaging (VVI).
Methods: One hundred and twenty consecutive subjects with no known cardiac disease had their echocardiograms analyzed using VVI after excluding those with QRS duration ≥120ms or LV ejection fraction (EF) <55%. Time to peak longitudinal, radial and circumferential velocities and strain were calculated. The study subjects were divided into two groups based on body mass index (BMI):obese (BMI ≥30) and non-obese (BMI <30). A multivariate analysis was performed (SPSS version 10).
Results: The final cohort included 95 patients; 69% females, mean age 55±16 years, mean QRS duration 84±9ms, and mean LVEF 61±8%. Demographic and clinical data were similar between groups. The occurrence of intra left ventricular dyssynchrony was higher in the obese group with 8% having longitudinal (Long) septal to lateral (S-L) wall delay >75ms, 76% having radial (Rad) S-L wall delay >75ms and 25% having circumferential (Circum) maximum (max) opposing wall delay >100ms when compared to non-obese subjects (0%, 36% and 0% respectively).
Conclusions: There was an increased prevalence of dyssynchrony in obese subjects, especially circumferential and radial dyssynchrony. Given that circumferential twist contributes importantly towards left ventricular function, this dyssynchrony may signal a mechanism by which obesity predisposes to development of heart failure.