Diffuse myocardial fibrosis by T1 mapping is associated with heart failure in pediatric primary dilated cardiomyopathy

Int J Cardiol. 2021 Jun 15:333:219-225. doi: 10.1016/j.ijcard.2021.03.023. Epub 2021 Mar 16.

Abstract

Background: In adult cardiomyopathy (CM), diffuse myocardial fibrosis is associated with adverse clinical outcome. However, its relevance in pediatric patients remains relatively unknown. The study aimed to evaluate myocardial extracellular volume (ECV) reflecting diffuse myocardial fibrosis with cardiovascular magnetic resonance (CMR) T1 mapping, and to analyze correlations with clinical and functional data in children and adolescents with different CM phenotypes.

Methods: Patients with primary dilated (DCM), hypertrophic (HCM) or left ventricular non-compaction CM (LVNC) were prospectively enrolled and compared with healthy controls. Study participants underwent standardized CMR with modified Look-Locker Inversion recovery (MOLLI) T1 mapping.

Results: In total, 33 patients (median age 12.0 years; DCM: n = 10, HCM: n = 13; LVNC: n = 10) and 7 controls (14.5 years) were included. DCM: ECV was higher than in controls (38.1 ± 7.5% vs. 27.2 ± 3.6%; p = 0.014). Patients with elevated ECV were younger than those with normal values (p = 0.044). ECV correlated with N-terminal pro brain natriuretic peptide (r = 0.66, p = 0.038), left ventricular ejection fraction (r = -0.63, p = 0.053), and stroke volume of left (r = -0.75, p = 0.013) and right ventricle (r = -0.67, p = 0.033). During a median follow-up of 25.3 months, 3 patients underwent heart transplantation (HTx), and 2 were listed for HTx. All 5 patients had elevated ECV.

Hcm/lvnc: ECV was within normal range in HCM (25.5 ± 4.5%) and LVNC (29.6 ± 4.2), and was not related with clinical and/or functional parameters.

Conclusions: Our results indicate an increased burden of diffuse myocardial fibrosis in relation with younger age in pediatric DCM. ECV was associated with clinical and biventricular functional markers of heart failure in DCM.

Keywords: Cardiomyopathy; Cardiovascular magnetic resonance; Extracellular volume; Fibrosis; Heart failure; Pediatric.

MeSH terms

  • Adolescent
  • Adult
  • Cardiomyopathies* / pathology
  • Cardiomyopathy, Dilated* / diagnostic imaging
  • Cardiomyopathy, Dilated* / pathology
  • Case-Control Studies
  • Child
  • Contrast Media
  • Fibrosis
  • Heart Failure* / pathology
  • Humans
  • Magnetic Resonance Imaging, Cine
  • Myocardium / pathology
  • Predictive Value of Tests
  • Stroke Volume
  • Ventricular Function, Left

Substances

  • Contrast Media