Importance of newer cardiac magnetic resonance-based risk markers for sudden death prevention in hypertrophic cardiomyopathy: An international multicenter study

Heart Rhythm. 2022 May;19(5):782-789. doi: 10.1016/j.hrthm.2021.12.017. Epub 2021 Dec 18.


Background: The sudden death (SD) risk stratification algorithm in hypertrophic cardiomyopathy (HCM) has evolved, underscored recently by novel cardiac magnetic resonance (CMR)-based risk markers (left ventricular apical aneurysm, extensive late gadolinium enhancement, and end-stage disease with systolic dysfunction) incorporated into the 2020 American Heart Association (AHA)/American College of Cardiology (ACC) HCM guidelines.

Objective: The purpose of this study was to assess the specific impact of newer, predominantly CMR-based risk markers in a large multicenter HCM population that underwent primary prevention implantable cardioverter-defibrillator (ICD) implants.

Methods: Longitudinal study of 1149 consecutive HCM patients from 6 North American and European HCM centers prospectively judged to be at high SD risk based on ≥1 AHA/ACC individual risk markers and prophylactically implanted with an ICD was performed. European Society of Cardiology (ESC) risk score was retrospectively analyzed with respect to the known clinical outcome.

Results: Of 1149 patients with an ICD, 162 (14%) experienced device therapy terminating ventricular tachycardia/ventricular fibrillation 4.6 ± 4.2 years after implant. CMR-based markers solely or in combination led to ICD implantation in 49 of the 162 patients (30%) experiencing device therapy. Particularly low ESC scores (<4%/5 years) would have excluded an ESC ICD recommendation for 67 patients who nevertheless experienced appropriate ICD therapy, including 26 with the CMR-based risk markers not part of the ESC formula.

Conclusion: Identification and incorporation of novel guideline-supported CMR-based risk markers enhance selection of HCM patients for SD prevention with ICDs. Absence of CMR-based markers from the ESC risk score accounts, in part, for it not identifying many HCM patients with SD events. These data support inclusion of CMR as a routine part of HCM patient evaluation and risk stratification.

Keywords: Cardiac magnetic resonance imaging; Hypertrophic cardiomyopathy; Implantable cardioverter-defibrillator; Risk stratification; Sudden death.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cardiomyopathy, Hypertrophic* / complications
  • Cardiomyopathy, Hypertrophic* / diagnosis
  • Cardiomyopathy, Hypertrophic* / therapy
  • Contrast Media
  • Death, Sudden, Cardiac / epidemiology
  • Death, Sudden, Cardiac / etiology
  • Death, Sudden, Cardiac / prevention & control
  • Defibrillators, Implantable* / adverse effects
  • Gadolinium
  • Humans
  • Longitudinal Studies
  • Magnetic Resonance Spectroscopy
  • Primary Prevention / methods
  • Retrospective Studies
  • Risk Assessment / methods
  • Risk Factors
  • Ventricular Fibrillation / etiology


  • Contrast Media
  • Gadolinium