Evaluation of cardiac and respiratory involvement in sarcoglycanopathies

Sarcoglycanopathies constitute a subgroup of limb-girdle recessive muscular dystrophies due to defects in sarcoglycan complex that comprises five dist inct transmembrane proteins called alpha-, beta-, gamma-, delta- and epsilo n -sarcoglycans. As it is well known that sarcoglycans are expressed both i n heart and in skeletal muscles and a complete deficiency in delta -sarcogl ycan is the cause of the Syrian hamster BIO.14 cardiomyopathy, we studied c ardiac and respiratory involvement in 20 patients with sarcoglycanopathies by clinical, electrocardiographic, echocardiographic, scintigraphic and spi rometric assessments. A normal heart function was found in 31.3% of all pat ients; a preclinical cardiomyopathy in 43.7%: an arrhythmogenic cardiomyopa thy in 6.3% and initial signs of dilated cardiomyopathy in 18.7%. In one pa tient the data were examined retrospectively. No correlation was found betw een cardiac and skeletal muscle involvement. With reference to the type of sarcoglycanopathy, signs of hypoxic myocardial damage occurred in beta-, ga mma- and delta -sarcoglycanopathies, while initial signs of a dilated cardi omyopathy in gamma- and delta -sarcoglycanopathies were found. A normal res piratory function was observed in 23.5% of all patients, a mild impairment in 35.4%, a moderate impairment in 29.4%, and a severe impairment in 11.7%. (C) 2001 Elsevier Science B.V, All rights reserved.