Improved Risk Stratification for Ventricular Arrhythmias and Sudden Death in Patients With Nonischemic Dilated Cardiomyopathy

J Am Coll Cardiol. 2021 Jun 15;77(23):2890-2905. doi: 10.1016/j.jacc.2021.04.030.

Abstract

Background: Risk stratification for ventricular arrhythmias (VA) and sudden death in nonischemic dilated cardiomyopathy (DCM) remains suboptimal.

Objectives: The goal of this study was to provide an improved risk stratification algorithm for VA and sudden death in DCM.

Methods: This was a retrospective cohort study of consecutive patients with DCM who underwent cardiac magnetic resonance with late gadolinium enhancement (LGE) at 2 tertiary referral centers. The combined arrhythmic endpoint included appropriate implantable cardioverter-defibrillator therapies, sustained ventricular tachycardia, resuscitated cardiac arrest, and sudden death.

Results: In 1,165 patients with a median follow-up of 36 months, LGE was an independent and strong predictor of the arrhythmic endpoint (hazard ratio: 9.7; p < 0.001). This association was consistent across all strata of left ventricular ejection fraction (LVEF). Epicardial LGE, transmural LGE, and combined septal and free-wall LGE were all associated with heightened risk. A simple algorithm combining LGE and 3 LVEF strata (i.e., ≤20%, 21% to 35%, >35%) was significantly superior to LVEF with the 35% cutoff (Harrell's C statistic: 0.8 vs. 0.69; area under the curve: 0.82 vs. 0.7; p < 0.001) and reclassified the arrhythmic risk of 34% of patients with DCM. LGE-negative patients with LVEF 21% to 35% had low risk (annual event rate 0.7%), whereas those with high-risk LGE distributions and LVEF >35% had significantly higher risk (annual event rate 3%; p = 0.007).

Conclusions: In a large cohort of patients with DCM, LGE was found to be a significant, consistent, and strong predictor of VA or sudden death. Specific high-risk LGE distributions were identified. A new clinical algorithm integrating LGE and LVEF significantly improved the risk stratification for VA and sudden death, with relevant implications for implantable cardioverter-defibrillator allocation.

Keywords: cardiac magnetic resonance; late gadolinium enhancement; nonischemic dilated cardiomyopathy; sudden death; ventricular arrhythmias.

Publication types

  • Multicenter Study
  • Observational Study

MeSH terms

  • Aged
  • Cardiomyopathy, Dilated / complications*
  • Cardiomyopathy, Dilated / diagnosis
  • Cardiomyopathy, Dilated / mortality
  • Death, Sudden, Cardiac / epidemiology*
  • Death, Sudden, Cardiac / etiology*
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Magnetic Resonance Imaging, Cine
  • Male
  • Middle Aged
  • Myocardium / pathology
  • Retrospective Studies
  • Risk Assessment / methods*
  • Risk Factors
  • Spain / epidemiology
  • Survival Rate / trends
  • Tachycardia, Ventricular / diagnosis
  • Tachycardia, Ventricular / etiology*
  • Tachycardia, Ventricular / mortality
  • United Kingdom / epidemiology