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Utilizing Percutaneous Ventricular Assist Devices in Acute Myocardial Infarction Complicated by Cardiogenic Shock
06:10

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Published on: June 12, 2021

Prognostic impact of inappropriate defibrillator shocks in a population cohort

Marc William Deyell1, Anzhen Qi, Santabhanu Chakrabarti

  • 1Heart Rhythm Services, Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada. mdeyell@providencehealth.bc.ca

Heart (British Cardiac Society)
|March 8, 2013
PubMed

Insights

Inappropriate implantable cardioverter-defibrillator (ICD) shocks were not linked to increased mortality or heart transplantation in a large patient cohort. This study suggests inappropriate ICD shocks may not lead to adverse clinical outcomes, even in high-risk patients.

Area of Science:

  • Cardiology
  • Medical Devices
  • Clinical Outcomes Research

Background:

  • Limited data exists on the clinical impact of inappropriate implantable cardioverter-defibrillator (ICD) shocks.
  • Understanding these associations is crucial for patient management and device programming.

Purpose of the Study:

  • To investigate the relationship between inappropriate ICD shocks and mortality or heart transplantation.
  • To analyze this association in a large cohort of patients receiving ICDs.

Main Methods:

  • A retrospective cohort study included 1698 patients who underwent ICD implantation between 1998 and 2008.
  • Multivariable Cox regression with time-dependent covariates was used to assess the risk of death and heart transplantation.
  • Appropriate and inappropriate ICD therapies were analyzed as independent factors.

Main Results:

  • Over a median follow-up of 30 months, 14.5% of patients died and 2.5% underwent heart transplantation.
  • Inappropriate ICD shocks were not associated with increased mortality or heart transplantation (adjusted HR=0.97, p=0.873).
  • Appropriate shocks, however, were significantly associated with adverse outcomes (adjusted HR=3.11, p<0.001).

Conclusions:

  • Inappropriate ICD shocks did not correlate with increased mortality or heart transplantation in this cohort.
  • This finding held true even for patients with severely impaired left ventricular function (ejection fraction <30%).
  • The results challenge the assumption that inappropriate ICD shocks directly lead to adverse clinical outcomes.
Abstract

Keywords:
Arrhythmias

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