Primary Systemic Carnitine Deficiency Complicated With Severe Cardiomyopathy: A Case Report

Figures

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  FIGURE 1. Transthoracic color‐Doppler echocardiography at admission (November 2, 2024). Two representative views showing a markedly dilated left atrium and left ventricle, thickened mitral‐valve leaflets, and a mosaic systolic color jet consistent with severe mitral regurgitation.

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  FIGURE 2. Twenty‐four‐hour Holter monitoring during hospitalization. Heart‐rate trends, ST‐segment analysis and heart‐rate‐variability (HRV) parameters. The first recording (hospital Day 8) showed sinus tachycardia (average heart rate 100 beats/min), diffuse ST‐segment depression and reduced HRV (SDNN 120 ms, rMSSD 49 ms, pNN50 18.7%); the repeat recording (hospital Day 18) showed a lower average heart rate (79 beats/min), resolution of ST‐segment shifts and improved HRV (SDNN 193 ms, rMSSD 81 ms, pNN50 37.6%). Holter monitoring was used to screen for occult arrhythmias and to track autonomic functional recovery during treatment of severe cardiomyopathy.

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  FIGURE 3. Genetic findings of the trio. (a) Family pedigree. The proband (II‐1, arrow) carries SLC22A5 NM_003060.4 c.338G>A (p.Cys113Tyr) in homozygous state (filled symbol, affected), whereas her father (I‐1) and mother (I‐2) are each heterozygous carriers (half‐filled symbols), consistent with autosomal‐recessive inheritance; blue text indicates carriage (+) or absence (−) of the maternally inherited chr3q29 duplication (mat). (b) Chromosome 3 copy‐number plots obtained by low‐pass whole‐genome sequencing for the proband, father and mother, showing the 3q29 duplication (seq[hg19]dup(3) (q29), chr3:G.197665483_197855472dup; approximately 190 kb; copy number = 3) in the proband and mother and its absence in the father, confirming maternal inheritance. VUS, variant of uncertain significance.