Beneficial Effect of Bradycardia Tachycardia Response (BTR) Algorithm on VT Detection in the Presence of Rate Smoothing

• Published in: Pacing and clinical electrophysiology Vol. 35; no. 5; pp. 586 - 591
• Main Authors: NIKOLIDAKIS, SAVVAS, LURIA, DAVID, WEISEMBERG, JESSICA SHAYOVICH, TANAMI, NECHEMYA, LEV, DAVID BAR, GUREVITZ, OSNAT, SHAM'A, RAED ABU, ELDAR, MICHAEL, FRIEDMAN, PAUL, GLIKSON, MICHAEL
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01.05.2012; Wiley
• Subjects: Algorithms; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Bradycardia - diagnosis; Bradycardia - therapy; bradycardia tachycardia response; Cardiac dysrhythmias; Cardiac Pacing, Artificial - methods; Cardiology. Vascular system; Computer Simulation; Diagnosis, Computer-Assisted - methods; dual-chamber defibrillator; Emergency and intensive cardiocirculatory care. Cardiogenic shock. Coronary intensive care; Heart; Humans; Intensive care medicine; Medical sciences; Models, Cardiovascular; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Reproducibility of Results; Sensitivity and Specificity; Tachycardia, Ventricular - diagnosis; Tachycardia, Ventricular - therapy; Therapy, Computer-Assisted - methods; ventricular tachycardia detection; Intensive cardiocirculatory care; Arrhythmia; Instrumentation therapy; bradycardia tachycardia response; Cardiovascular disease; Ventricular tachycardia; Algorithm; Excitability disorder; Bradycardia; Heart disease; ventricular tachycardia detection; Diagnosis; Defibrillation; dual-chamber defibrillator; Defibrillator
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/j.1540-8159.2012.03342.x

Introduction: Rate smoothing algorithms, while known to help prevent ventricular tachyarrhythmias in some patients, have been shown to result in underdetection of ventricular tachycardia (VT) due to interaction between bradycardia pacing and tachycardia detection parameters. A new algorithm named Bradycardia Tachycardia Response (BTR) has been developed in order to prevent rate smoothing‐induced underdetection. The efficacy of BTR is not known. The aim of this study was to assess the effectiveness of BTR in preventing VT underdetection due to rate smoothing. Methods and Results: Two ICD models (TELIGEN and VITALITY AVT, Boston Scientific, St. Paul, MN, USA) bearing identical rate smoothing algorithms were connected to a VT simulator. Devices were programmed similarly except for the BTR feature that exists in TELIGEN only. The detection performance of both devices was tested using varying combinations of AV delay, rate smoothing down, and upper rate limit and compared between the two models. VT underdetection (delay or nondetection) occurred during pacing in 62% of the VT episodes with VITALITY AVT. In TELIGEN, all simulated VT episodes were detected appropriately as soon as their rates exceeded the programmed VT detection rate. Detection tended to be affected by higher upper rate, longer AV delays, and more aggressive rate smoothing. Conclusion: The BTR algorithm effectively counteracts VT detection delay caused by the interaction of rate smoothing with VT detection parameters, thus enabling safe use of the rate smoothing feature. (PACE 2012; 1–6)