Abstract 10610: Severity of Hypertrophy and Increased QTc Interval Predict Appropriate ICD Therapies in Hypertrophic Cardiomyopathy
Background: Hypertrophic cardiomyopathy (HCM) is the leading cause of sudden cardiac death (SCD) in those aged <35 years. Implantation of a cardioverter defibrillator (ICD) is offered to select patients at increased risk of SCD. We sought to determine factors predicting appropriate ICD therapy in a large cohort of HCM patients.
Methods: Patients attending the HCM clinic at Royal Prince Alfred Hospital who have undergone ICD insertion were included. Baseline clinical data was collected, including clinical evaluation, ECG, 2D echocardiography, and ICD interrogation data. The primary endpoint was an appropriate therapy from the ICD.
Results: A total of 144 HCM patients (males=63%) with an ICD were included, with a mean follow-up of 6 ± 4 years (range 0-21 yrs). Of these, 16 (11%) patients received an appropriate therapy, 15 (10%) had an inappropriate event, and 3 (2%) had both. 12/19 (63%) appropriate events were for VT and 7/19 (37%) for VF. Mean time to appropriate therapy was 98 ± 87 days post-implant. Increased severity of septal hypertrophy and prolonged QTc were significantly associated with appropriate events.
Conclusions: Severity of septal hypertrophy was associated with appropriate ICD events in established high-risk patients with HCM. We also identified prolonged QTc as a novel clinical predictor of ventricular arrhythmias in HCM.
- © 2012 by American Heart Association, Inc.