Abstract 14183: Some Like It Cool - Seasonal Temperature, as Well as Clinical And Demographic Factors, Predicts Compliance With the Wearable Cardioverter Defibrillator
Introduction: The wearable cardioverter defibrillator (WCD) is a non-invasive alternative to the ICD in patients requiring short-term protection against sudden cardiac death (SCD). While compliance is satisfactory on average, identification of factors which predict lower compliance may yield improvable targets.
Hypothesis: Seasonal, clinical, and demographic variables influence compliance with the WCD.
Methods: We analyzed a large post-marketing registry of WCDs (ZOLL LifeVest registry, n=11,341). Compliance was measured as hours of use per day, as determined by stored electrode contact data. Monthly national average temperature data were obtained from the National Oceanographic and Atmospheric Administration. Univariate and multivariate logistic regression analysis of seasonal and clinical factors was performed to determine predictors of compliance.
Results: Multivariate analysis showed that younger age (p<0.001), male gender (20.2 v 20.6 hours/day, p<0.001) and familial conditions with a high risk of SCD (18.2 v 20.3 hours/day, p<0.001) were associated with lower compliance. Prior cardiac arrest (20.5 v 20.3 hours/day, p=0.002), recent myocardial infarction (20.9 v 20.3 hours/day, p<0.001) or recent diagnosis of cardiomyopathy (21.7 v 20.3, p=0.001) predicted better compliance. Use in summertime was 0.65 hours/day less than wintertime (p<0.001) (figure). Compliance was not influenced by model type (p=0.381).
Conclusions: Compliance with the WCD is associated with seasonal temperature, as well as a number of clinical and demographic factors, which should be considered when educating patients for this device. Refinements in WCD design might improve tolerability in warmer weather, and measures to improve compliance in younger and male patients may be helpful to maximize clinical benefit of the WCD.
- © 2011 by American Heart Association, Inc.