Sudden Cardiac Arrest and Takotsubo-Like Cardiomyopathy as the Initial Presentation of Primary Carnitine Deficiency.

backgroundPrimary carnitine deficiency (PCD) is a rare yet treatable disorder of the carnitine cycle causing defective fatty acid oxidation. PCD presents with considerable phenotypic variability, including sudden cardiac death as the initial manifestation. CASE SUMMARY: An 18-year-old female born in India presented with a ventricular fibrillation cardiac arrest. Cardiac evaluation was notable for normal anatomy, nonspecific repolarization changes on electrocardiogram, and cardiac magnetic resonance image showing a Takotsubo-like cardiomyopathy phenotype. Genetic testing identified a homozygous pathogenic variant in SLC22A5 (c.43G>T; p.Gly15Trp) consistent with autosomal recessive PCD. Confirmatory testing demonstrated severely reduced total carnitine levels, which normalized after carnitine supplementation. DISCUSSION: PCD is a rare metabolic condition which can manifest with malignant ventricular arrhythmias. While PCD is routinely detected via the newborn metabolic screen, it should be considered in individuals with cardiac abnormalities who were born internationally. TAKE-HOME MESSAGE: This case highlights malignant ventricular arrhythmia as an initial presentation of PCD.