Inheritance: X-linked
Gene affected: GLA on Xq22.1
Enzyme affected: alpha-galactosidase A
Features of the cardiomyopathy:
(1) left ventricular hypertrophy (usually concentric, occasionally asymmetric)
(2) variable right ventricular hypertrophy
(3) repolarization abnormalities
(4) left ventricular systolic and diastolic dysfunction
(5) associated with dyspnea, angina, palpitations and/or syncope
The cardiomyopathy tends to progress with age. Males tend to be symptomatic at a younger age but both men and women may be affected.
Other cardiac abnormalities include:
(1) disorders of the conduction system with arrhythmias
(2) valvular dysfunction
(3) coronary artery disease
(4) peripheral arterial disease
A male can be diagnosed by measuring alpha-galactosidase A activity in peripheral blood leukocytes. Identifying a female carrier may require GLA gene sequencing or identification of a known familial mutation since enzyme activity within leukocytes is often normal.
