Heart Rhythm O2 (Jun 2020)

Implantable cardioverter-defibrillator programming after first occurrence of ventricular tachycardia in the Multicenter Automatic Defibrillator Implantation Trial–Reduce Inappropriate Therapy (MADIT-RIT)Key Findings

  • Mehmet K. Aktas, MD, MBA, FHRS,
  • Amanda L. Bennett, MD,
  • Arwa Younis, MD,
  • Valentina Kutyifa, MD, PhD, FHRS,
  • Bronislava Polonsky, MS,
  • Scott McNitt, MS,
  • Wojciech Zareba, MD, PhD,
  • Spencer Rosero, MD,
  • Ilan Goldenberg, MD

Journal volume & issue
Vol. 1, no. 2
pp. 77 – 82

Abstract

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Background: Implantable cardioverter-defibrillator (ICD) programming to novel settings can reduce the risk of inappropriate therapies. Objective: The purpose of this study was to evaluate the impact of novel ICD programming after the first occurrence of ventricular tachycardia (VT). Methods: In MADIT-RIT (Multicenter Automatic Defibrillator Implantation Trial–Reduce Inappropriate Therapy) patients who experienced a first occurrence of VT, the risk of subsequent inappropriate and appropriate ICD therapies and adverse cardiovascular events by ICD programming to Arm A (conventional: VT ≥170 bpm), Arm B (high rate: VT ≥200 bpm), or Arm C (duration delay: ≥60-second delay before therapy ≥170 bpm) was determined. Results: Among 205 patients, ICD programming changes were made in 30 patients (15%) after they experienced a VT episode; 117 patients (57%) were programmed to Arm A settings and 88 patients (43%) to Arm B/C settings. At 15-month follow-up, the cumulative probability of inappropriate ICD therapy was significantly lower in Arm B/C compared to Arm A (9% vs 20%; log-rank P = .029 for overall difference). The rate of appropriate ICD therapy also was significantly lower in Arm B/C compared to Arm A (32% vs 64%; log-rank P = .001 for overall difference). Multivariate analysis showed that patients programmed to Arm B/C after the occurrence of VT had a 71% reduction (P = .02) in the risk of inappropriate ICD therapies and a 43% reduction (P = .02) in the risk of appropriate ICD therapies compared to Arm A. Conclusion: The benefit of high-rate cutoff or duration delay settings in patients with an ICD is maintained after the first occurrence of VT.

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