Maternally inherited hypertrophic cardiomyopathy: a manifestation of mitochondrial DNA mutations--clinical course in two families.
In the past decade, maternally inherited disorders have been described manifesting as hypertrophic cardiomyopathy. These are primarily associated with defects in oxidative metabolism due to an alteration in mitochondrial DNA. Although the biochemistry and molecular biology is well-defined, there is little information regarding clinical presentation and course. Reported manifestations can be broad and can include myopathy, encephalopathy, stroke-like episodes, hearing loss, cardiomyopathy, multiorgan dysfunction and sudden death. Predominant or exclusive involvement of the heart is rare. We report the clinical presentations, investigations, pathologic findings, and clinical course in two families with two mitochondrial tRNA defects with exclusive cardiac involvement and demonstrable clinical heterogeneity based on the percentage of mutant tRNA.
Dipchand
A I
AI
Department of Pediatrics, The Hospital for Sick Children and the University of Toronto Faculty of Medicine, 555 University Avenue, Toronto, Ontario, Canada M5G 1X8.
Tein
I
I
Robinson
B
B
Benson
L N
LN
D000293:Adolescent; D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000097:blood / Q000175:diagnosis / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006333:Heart Failure / Q000175:diagnosis / Q000235:genetics; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D017240:Mitochondrial Myopathies / Q000150:complications / Q000235:genetics*; D017354:Point Mutation / Q000235:genetics; D012355:RNA, Transfer, Ile / Q000235:genetics; D012189:Retrospective Studies; D012729:Sex Chromosome Aberrations / Q000235:genetics; D014960:X Chromosome
D004272:DNA, Mitochondrial; D012355:RNA, Transfer, Ile