Abstract 14042: Weight Loss Favorably Impacts Left Ventricular Mass and Wall Thickness by CMR and CT in Patients With Hypertrophic Cardiomyopathy: A Retrospective Case Series

Abstract

Introduction: Hypertrophic Cardiomyopathy (HCM) is a relatively common inherited heart disease with variable phenotypic expression. While pathogenic variants in sarcomeric genes are considered responsible for the development of left ventricular (LV) hypertrophy, environmental modulation of phenotype may explain the known heterogeneity. Obesity is common in HCM patients and is associated with increased LV mass in the general population. Hypothesis: We hypothesized that weight loss in obese patients with HCM would be associated with a decrease in LV mass and maximal wall thickness. Methods: Patients with HCM who achieved therapeutic weight loss and underwent cardiac MRI (CMR) or computed tomography (CT) before and afterwards were included. Standard LV measurements including wall thickness in an 18-segment model were performed blindly with respect to name, time and BMI for un-biased comparison. Results: We included 6 patients (2 female, age 55 ± 6.5 years, baseline BMI = 36.7 ± 5.2 kg/m 2 ) who achieved 16.3 ± 10.8 kg weight loss after 35 ± 12 months with diet and exercise (n=4) or bariatric surgery (n=2). After weight loss, we observed a mean proportional decrease in total LV mass of 25 ± 16% (p=0.004), and a 19 ± 7% decrease in indexed LV mass (p=0.007). Furthermore, there was a numerical decrease in mean wall thickness in 14 out of 18 LV segments measured; 9 segments had more than a 10% decrease. The most noticeable changes were at the basal inferolateral wall (25 ± 13% decrease) and basal inferoseptum (19 ± 18%) decrease (Table). Conclusions: In this series of patients with HCM, weight loss favorably affected LV mass and wall thickness. Further research is needed to explore the impact of weight loss on HCM phenotypic expression and symptoms.