Design of A Test Protocol for Implantable Defibrillators

Pelowitz, David

Abstract

Electrical management of potentially lethal arrhythmias has been found to dramatically improve survival rates in candidates at risk of sudden cardiac death. Over 40,000 Implantable cardioverter/defibrillators (ICDs) have been implanted since initial FDA approval in 1985. False positive delivery of shock remains a major problem and newer devices are being designed with more sophisticated arrhythmia detection schemes and tiered- therapy protocols. The goal of this project is to develop a system to standardize testing and device evaluation for future devices. Such a system will assess sensitivity and specificity of detection algorithms and device response to yield reliable statistics on safety and efficacy. In Phase l we will demonstrate the feasibility of designing a standardized test for exercising the arrhythmia detection mechanisms contained within ICDs on a variety of both simulated and clinical experimental data. We will: 1) complete the development of a cardiac simulator of atrial and ventricular events which can mimic any cardiac arrhythmia, and determine device response; 2) create a proprietary test set of clinical data previously recorded during electrophysiology studies, as a companion to an existing training set which has been made available by us to commercial designers of implantable devices; and 3) design a test protocol utilizing both simulated and experimental signals for evaluation of next-generation device performance in such categories as oversensing, undersensing, errors in rhythm diagnosis, errors in pacing therapy and/or shock delivery. The development of an independent testing facility and standardized testing protocol for use by the industry is our goal.

Proposed Commercial Applications

The Food and Drug Administration is presently developing performance standards to be applied to future implantable cardioverter/defibrillators submissions for approval. We believe that the establishment of an independent testing facility would facilitate the assessment of comparative device performance and provide valuable safety and efficacy information.