Copyright © 1998 by the European Society of Cardiology.
A clinical, echocardiographic and genetic characterization of a Danish kindred with familial amyloid transthyretin methionine 111 linked cardiomyopathy
a Department of Cardiology, Bispebjerg Hospital, University of Copenhagen
b Department of Medicine B, Division of Cardiology, Rigshospitalet, University of Copenhagen, Denmark
c Department of Rheumatology, University Hospital of Tromsø Norway
accepted October 30, 1997
Aims
To identify carriers and non-carriers of the mutant transthyretin methionine 111 linked familial amyloid disease, to detect early signs of the restrictive cardiomyopathy and other clinical manifestations characteristic of this inheritable disease
Methods and Results
Out of 125 living family members 99 were available for clinical, echocardiographic and genetic examination. Twenty-five family members were heterozygous carriers of the mutant transthyretin methionine 111 genotype, while 74 were non-carriers. Among the 25 carriers, none had overt clinical signs of heart disease. Eight carriers, all above the age of 35, showed echo-cardiographic abnormalities suggestive of developing or manifest restrictive cardiomyopathy. Three had biopsy-verified transthyretin-related amyloid cardiomyopathy. None of the 15 carriers in the younger age group exhibited aberrant echocardiographic patterns. Nine carriers had carpal tunnel syndrome as opposed to none of the non-carriers.
Conclusion
For early detection of familial amyloid cardiomyopathy, echocardiography is the investigation of choice. The first sign is diastolic dysfunction detected as an abnormal relaxation pattern. The appearance of echo-cardiographic aberrations solely in the older age group suggests that the cardiomyopathy is a late onset disease. Carpal tunnel syndrome appears to be the earliest presenting clinical symptom. A curative treatment seems to be an early liver transplantation.
Key Words: Amyloid cardiomyopathy hereditary transthyretin echocardiography
f1 Correspondence: I. Hastrup Svendsen, MD, Department of Cardiology, Bispebjerg Hospital, University of Copenhagen, DK-2400 Copenhagen, Denmark.