Intrafamilial variability of noncompaction of the ventricular myocardium.
BACKGROUND
Noncompaction of the ventricular myocardium (NVM) is a relatively uncommon form of cardiomyopathy characterized by a highly trabeculated myocardium. This report describes the clinical and genetic evaluation of a 3-generation kindred.


METHODS
Family members were initially evaluated by 2-dimensional echocardiography. Most family members with signs of NVM were further evaluated by magnetic resonance imaging. Genetic analyses included mutational screening of the taffazin (TAZ) and alpha-dystrobrevin (DTNA) genes.


RESULTS
Eight family members had signs of NVM. Considerable interindividual variation was noted in terms of spatial distribution and severity of affected regions and ventricular dysfunction. Depending on which of 2 previously proposed quantitative diagnostic criteria were used and where ventricular myocardial measurements were taken, between 4 and 7 of these individuals had findings that were considered diagnostic. Magnetic resonance imaging served as a useful adjunct for confirming or establishing diagnoses in all 8 individuals. No mutation was found in TAZ or DTNA.


CONCLUSIONS
This kindred demonstrates the remarkably wide phenotypic spectrum that can be seen in familial cases of NVM, ranging from prenatal/neonatal lethality to a complete lack of symptoms. The fact that all 8 affected individuals either have shown improvement in ventricular function or symptoms during childhood or have been asymptomatic indicates that NVM can have a relatively benign course. The degree and nature of cardiac involvement are also quite varied, and there is a weak correlation with ventricular function and symptoms. Evaluation of families with NVM requires careful assessment that uses a combination of imaging techniques and diagnostic criteria.
Johnson
Mark T
MT
Department of Genetics, Case University, Cleveland, OH, USA.
Zhang
Shaoxiong
S
Gilkeson
Robert
R
Ameduri
Rebecca
R
Siwik
Ernest
E
Patel
Chandrakant R
CR
Chebotarev
Oleg
O
Kenton
Alexander B
AB
Bowles
Karla R
KR
Towbin
Jeffrey A
JA
Robin
Nathaniel H
NH
Brozovich
Frank
F
Hoit
Brian D
BD
D000293:Adolescent; D009202:Cardiomyopathies / Q000150:complications / Q000175:diagnosis* / Q000196:embryology / Q000235:genetics*; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D014644:Genetic Variation; D006352:Heart Ventricles; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D010641:Phenotype; D016216:Ultrasonography, Prenatal; D018754:Ventricular Dysfunction / Q000209:etiology / Q000503:physiopathology