Phenotype, outcomes and natural history of early-stage non-ischaemic cardiomyopathy

Eur J Heart Fail. 2023 Nov;25(11):2050-2059. doi: 10.1002/ejhf.3037. Epub 2023 Oct 11.

Abstract

Aims: To characterize the phenotype, clinical outcomes and rate of disease progression in patients with early-stage non-ischaemic cardiomyopathy (early-NICM).

Methods and results: We conducted a prospective observational cohort study of patients with early-NICM assessed by late gadolinium enhancement cardiovascular magnetic resonance (CMR). Cases were classified into the following subgroups: isolated left ventricular dilatation (early-NICM H-/D+), non-dilated left ventricular cardiomyopathy (early-NICM H+/D-), or early dilated cardiomyopathy (early-NICM H+/D+). Clinical follow-up for major adverse cardiovascular events (MACE) included non-fatal life-threatening arrhythmia, unplanned cardiovascular hospitalization or cardiovascular death. A subset of patients (n = 119) underwent a second CMR to assess changes in cardiac structure and function. Of 254 patients with early-NICM (median age 46 years [interquartile range 36-58], 94 [37%] women, median left ventricular ejection fraction [LVEF] 55% [52-59]), myocardial fibrosis was present in 65 (26%). There was no difference in the prevalence of fibrosis between subgroups (p = 0.90), however fibrosis mass was lowest in early-NICM H-/D+, higher in early-NICM H+/D- and highest in early-NICM H+/D+ (p = 0.03). Over a median follow-up of 7.9 (5.5-10.0) years, 28 patients (11%) experienced MACE. Non-sustained ventricular tachycardia (hazard ratio [HR] 5.1, 95% confidence interval [CI] 2.36-11.00, p < 0.001), myocardial fibrosis (HR 3.77, 95% CI 1.73-8.20, p < 0.001) and diabetes mellitus (HR 5.12, 95% CI 1.73-15.18, p = 0.003) were associated with MACE in a multivariable model. Only 8% of patients progressed from early-NICM to dilated cardiomyopathy with LVEF <50% over a median of 16 (11-34) months.

Conclusion: Early-NICM is not benign. Fibrosis develops early in the phenotypic course. In-depth characterization enhances risk stratification and might aid clinical management.

Keywords: Fibrosis; Non-ischaemic cardiomyopathy; Risk stratification.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Cardiomyopathies* / diagnosis
  • Cardiomyopathies* / epidemiology
  • Cardiomyopathy, Dilated* / diagnosis
  • Cardiomyopathy, Dilated* / epidemiology
  • Contrast Media
  • Female
  • Fibrosis
  • Gadolinium
  • Heart Failure*
  • Humans
  • Magnetic Resonance Imaging, Cine / methods
  • Male
  • Middle Aged
  • Myocardial Ischemia*
  • Prospective Studies
  • Stroke Volume
  • Ventricular Function, Left

Substances

  • Contrast Media
  • Gadolinium