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Competing risks in patients with primary prevention implantable cardioverter-defibrillators: Global Electrical

Jonathan W Waks1, Kazi T Haq2, Christine Tompkins3

  • 1Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center, Boston, Massachusetts.

Heart Rhythm
|March 8, 2021
PubMed

Insights

Global electrical heterogeneity (GEH) predicts appropriate ICD therapies in heart failure patients. Spatial ventricular gradient (SVG) direction and magnitude, and QRS-T angle are key indicators for sudden cardiac death risk.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Heart Failure Management

Background:

  • Global electrical heterogeneity (GEH) is linked to sudden cardiac death in the general population.
  • The role of GEH in predicting outcomes for heart failure patients receiving primary prevention (PP) implantable cardioverter-defibrillators (ICDs) remains unclear.

Purpose of the Study:

  • To determine if GEH is associated with sustained ventricular tachycardia/ventricular fibrillation (VT/VF) leading to appropriate ICD therapies in heart failure patients with PP ICDs.

Main Methods:

  • A multicenter retrospective cohort study analyzed 2668 patients.
  • GEH was assessed using spatial ventricular gradient (SVG) direction and magnitude, QRS-T angle, and sum absolute QRST integral from preimplant ECGs.
  • Survival analysis compared associations with appropriate ICD therapies versus all-cause death.

Main Results:

  • Adjusted analyses revealed SVG elevation, SVG azimuth, SVG magnitude, and QRS-T angle were independently associated with appropriate ICD therapies.
  • SVG magnitude showed a protective association (HR 0.75).
  • Sum absolute QRST integral demonstrated differential associations based on cardiomyopathy type (interaction P = .022).

Conclusions:

  • GEH is an independent predictor of appropriate ICD therapies in patients with PP ICDs.
  • The spatial orientation of the SVG vector differs between patients experiencing VT/VF and those with other outcomes.
Abstract

Keywords:
Competing riskGlobal electrical heterogeneityHeart failureImplantable cardioverter-defibrillatorsVentricular tachycardia/Ventricular fibrillation

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