Left ventricular noncompaction cardiomyopathy and short QT syndrome due to primary carnitine deficiency

Ann Noninvasive Electrocardiol. 2023 Nov;28(6):e13077. doi: 10.1111/anec.13077. Epub 2023 Sep 1.

Abstract

We report the case of a 13-year-old female patient presenting with presyncope and palpitations. Her electrocardiogram revealed an abbreviation of the rate-corrected QT interval with imaging showing significant left ventricular dysfunction. Carnitine levels were measured as part of her diagnostic workup, discovering a rare, reversible cause of short QT syndrome (SQTS) and associated cardiomyopathy-primary carnitine deficiency (PCD) caused by a homozygous mutation in the SLC22A5 gene, leading to an in-frame deletion mutation (NP_003051.1:p.Phe23del) affecting the organic cation transporter 2 (OCTN2) protein. Following the treatment with oral carnitine supplementation, her QT interval returned to within the normal range with significant improvement in left ventricular function.

Keywords: cardiomyopathy; carnitine deficiency; short QT syndrome.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Arrhythmias, Cardiac*
  • Cardiomyopathies* / complications
  • Cardiomyopathies* / diagnostic imaging
  • Cardiomyopathies* / genetics
  • Carnitine / deficiency*
  • Carnitine / genetics
  • Carnitine / therapeutic use
  • Electrocardiography
  • Female
  • Humans
  • Hyperammonemia*
  • Muscular Diseases*
  • Mutation
  • Organic Cation Transport Proteins* / genetics
  • Solute Carrier Family 22 Member 5 / genetics
  • Syndrome

Substances

  • Organic Cation Transport Proteins
  • Solute Carrier Family 22 Member 5
  • Carnitine
  • SLC22A5 protein, human

Supplementary concepts

  • Systemic carnitine deficiency
  • Short Qt Syndrome