Abstract 12556: Prevalence of Hypertension and Left Ventricular Hypertrophy in Adolescents Following Left Ventricular Outflow Tract Obstruction Repair

Abstract

Introduction: Left ventricular outflow tract obstructions predispose patients to increased lifetime risk of cardiovascular events even after successful repair (rLVOTO). Left ventricular hypertrophy (LVH) is an adaptive response to elevated afterload and is a predictor of cardiovascular events in adulthood. The prevalence of elevated blood pressure (SBP) and LVH in youths with rLVOTO is limited. Methods: Retrospective analysis of rLVOTO patients between 2012-2019, age 13-17 years with documented body mass index (BMI), SBP, LVOT velocity and left ventricular mass indexed to height (LVMi). Moderate LVOTO was defined as peak velocity ≥ 3 m/s. Patients categorized into normotensive (NT, SBP < 120 mm Hg), elevated (E-BP, 120 ≤ SBP < 130 mm Hg), Stage 1 HTN (HTN-1, 130 ≤ SBP < 140 mm Hg) and Stage 2 HTN (HTN-2, SBP ≥ 140 mm Hg). Prevalence of LVH was reported in each group (pediatric cutoff of LVMi-HT 2.7 ≥ 38.6 g/ht 2.7 ). Results: A total of 193 patients met criteria (age 15.6 ± 1.4 years), 135/193 (70%) male, SBP 120±13 mm Hg, and LVMi-HT 2.7 36.2±9.8 g/ht 2.7 . Half were in the NT group (93/193 (48%)), 55/193 (28%) in E-BP, 32/193 (17%) in HTN-1, and 13/193 (7%) in HTN-2 with no difference in BMI. Prevalence of LVH increased with higher SBP with 24/93 (26%) in NT, 21/55 (38%) in E-BP, 14/32 (43%) in HTN-1, and 4/13 (31%) in HTN-2. 124/193 (64%) had no residual LVOT gradient, 69/193 (36%) with residual LVOT gradient. 52/69 (75%) had LVOT < 3 m/s, of these 12/52 (23%) had ≥ HTN-1. 17/69 (25%) had residual LVOTO ≥ 3 m/s, of these 6/17 (35%) had ≥ HTN-1. No difference in LVMi found between no or mild LVOTO groups (35.9±13 vs 35.6±10 g/ht 2.7 , p = NS). Higher LVMi was found in the LVOTO ≥ 3 m/s group (41.5±13 g/ht 2.7 , p = 0.01 compared to both no or mild LVOTO). Conclusions: Youths with rLVOTO have a high prevalence of elevated BP, HTN, and LVH. When stratified by LVOTO severity, presence of ≥ HTN-1 was common with increased LVMi. No difference in BMI was observed among abnormal SBP groups suggesting BMI is not solely responsible for the increased LVMi. Longitudinal studies are needed to define the impact of rLVOTO and HTN on LVH over time. Our findings support early surveillance and management of hypertension in patients following LVOTO repair to help minimize the risk of future cardiovascular events related to LVH.