Abstract 16717: Should Routine DFT Testing be Performed at Device Implant? Results From a Meta-Analysis
Introduction: Defibrillation threshold (DFT) testing at the time of internal cardiac defibrillator (ICD) implant has become standard practice. Implantation techniques have evolved and recent devices are efficient with improved safety margins for defibrillation. Moreover DFT testing may be associated with complications. Consequently there is an emerging change in practice. Studies comparing the safety and benefits of DFT versus no DFT are small, mostly retrospective and controversial. We aimed to compare the safety and benefits of DFT testing to no DFT testing at the time of ICD implantation using meta-analytical methods.
Methods: Medline and Embase were searched for published (1966-2013) studies comparing outcomes between patients who received DFT testing at the time of implant and those who did not. Manual search by cross-referencing was also performed. Studies that did not report all cause mortality were excluded. As studies were heterogenous (cochran’s Q test p <0.05), we used a random effect model for stringency.
Results: Meta-analysis of seven retrospective, and two prospective studies with 5233 patients (mean age 64 yrs) with a median follow up of 2 years showed that the primary endpoint, all cause mortality did not significantly differ between patients that received DFT testing and those that did not [HR-1.13 (0.83-1.53)]. Secondary endpoints, ATP or appropriate ICD shocks [HR-0.66 (0.39-1.11)] and successful ICD therapies [HR-0.59 (0.27-1.30)] were also similar between the two groups. The DFT testing group was comparable to the no DFT testing group in variables including anti-arrhythmic drug use, ischemic cardiomyopathy, EF, and age but had significantly more males (90% vs 80%, p<0.05). A Meta-regression analysis showed that the effect size did not interact with any of these variables.
Conclusions: Avoiding routine DFT testing at the time of device implant does not adversely affect patient outcome.
- © 2013 by American Heart Association, Inc.