Abstract 20368: Younger Age Increases the Risk for Inappropriate Shocks in Hypertrophic Cardiomyopathy Patients With Implantable Cardioverter Defibrillators
Introduction: Survival benefit due to implantable cardioverter defibrillator (ICD) therapy is well documented in hypertrophic cardiomyopathy (HCM). However, ICD therapy may be inappropriate and a risk of sudden death in patients ≥ 60 has been recognized. Age stratification of ICD shock by decade is unknown. Our purpose was to investigate timing of ICD shocks by decade and determine the burden of device therapy for treatment of ventricular tachycardia (VT) and ventricular fibrillation (VF).
Methods: This is a retrospective review at a single high volume tertiary referral center of all patients seen at the HCM clinic who had an ICD placed between 2003-September 2013, with serial follow up. Shocks received for VF/VT were defined appropriate. Shocks for all other rhythms were considered inappropriate.
Results: There were 440 patients that met criteria, and 52 (11.8%) received a shock. Mean age was 53 ± 13 (mean decade 50), and 16 were female (31%). Of 100 shocks received in 52 patients, 39 were inappropriate. Odds of receiving an inappropriate shock in a female was 0.63 times that of a male (95% CI 0.180-1.012). Patients in their 3rd decade had the highest percentage of inappropriate shocks received (62.5%) with more than half being inappropriate. Patients ≤ 50 years old had increased likelihood of receiving inappropriate shocks as compared to those ≥ 50 (p=0.05). As age decreases, one is more likely to receive an inappropriate shock (p <0.05).
Conclusions: Almost 40% of shocks were inappropriate. While younger patients received less shocks overall, a high percentage of those were inappropriate. As age increased, shocks received by patients were more likely to be appropriate. Few shocks were received by patients in their 80th decade and none were inappropriate. Risks versus benefits of potentially inappropriate AICD therapy should be considered in young patients prior to AICD implantation.
Author Disclosures: A.J. McCambridge: None. E.R. Fenstad: None. S.H. Sheldon: None. A.M. Sugrue: None. J.B. Geske: None. S.R. Ommen: None. B.J. Gersh: None.
- © 2014 by American Heart Association, Inc.