Cardiomyopathy in children with mitochondrial disease; clinical course and cardiological findings

Eur Heart J. 2003 Feb;24(3):280-8. doi: 10.1016/s0195-668x(02)00387-1.


Aims: To determine the frequency of cardiomyopathy in children with mitochondrial disease and describe their clinical course, prognosis and cardiological manifestations.

Methods and results: Of 301 children with CNS and neuromuscular disease referred to our institution in 1984 to 1999, 101 had mitochondrial disease. Seventeen patients had cardiomyopathy, diagnosed by echo-Doppler investigations, all of the hypertrophic, non-obstructive type. The onset of symptomatic mitochondrial disease ranged from birth to 10 years of age. Eight children had cytochrome-c oxidase deficiency, while the remaining nine had various defects. Cardiomyopathy was diagnosed from birth to 27 years. Left ventricular posterior wall and septal thickness were both increased: z-scores +4.6+/-2.6 and +4.3+/-1.6 (mean+/-SD), respectively. The left ventricular diastolic diameter z-score, +1.3+/-3.4, and fractional shortening, 24+/-13%, displayed marked variations. Nine patients developed heart failure. Eleven patients with cardiomyopathy died, including all eight with cytochrome-c oxidase deficiency, and one patient underwent a heart transplantation. Mortality in children with mitochondrial disease was higher in those with cardiomyopathy (71%) than those without (26%) (P<0.001).

Conclusions: In children with mitochondrial disease, cardiomyopathy was common (17%) and was associated with increased mortality. The prognosis for children with cytochrome-c oxidase deficiency and cardiomyopathy appeared to be particularly unfavorable.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Cardiomyopathy, Hypertrophic / etiology*
  • Cardiomyopathy, Hypertrophic / pathology
  • Child
  • Child, Preschool
  • Echocardiography, Doppler / methods
  • Electrocardiography / methods
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Mitochondrial Diseases / complications*
  • Mitochondrial Diseases / pathology
  • Prognosis
  • Survival Analysis