Is left ventricular hypertrabeculation/ noncompaction a cardiac manifestation of Fabry's disease?

Some types of hypertrophic cardiomyopathy are due to cardiac Fabry's disease. Since left ventricular hypertrabeculation/noncompaction (LVHT) is regarded a subtype of hypertrophic cardiomyopathy, we looked for the alpha-galactosidase levels in blood leukocytes of LVHT patients.

Included were male patients in whom LVHT was diagnosed between June 1995 and September 2002. Echocardiographic criteria for LVHT were 1) >3 trabeculations protruding from the left ventricular wall, apically to the papillary muscles, visible in 1 image plane, and 2) intertrabecular spaces perfused from the ventricular cavity, as visualised on colour Doppler imaging. Trabeculations were defined as structures with the same echogenicity as the myocardium and moving synchronously with the ventricular contractions. Excluded were patients with known neuromuscular disorders. All patients were asked for systemic manifestations of Fabry's disease and blood tests were taken. The alpha-galactosidase-A activity was determined by means of an established fluorometric assay in blood leukocytes.

Forty-one patients were invited and 26 accepted the invitation. The remaining patients had died (n=5), lived abroad (n=5) or were unwilling (n=5). Among the 26 patients, aged 28-78 years, who followed the invitation, one had renal failure due to renal shrinkage and one had suffered from a stroke 3 years previously. Leukocyte alpha-galactosidase levels ranged from 70 to 188 nM/mg Prot/h (normal: > or =42 nM/mg Prot/h). In none of the patients was the alpha-galactosidase level reduced.

LVHT does not seem to be a manifestation of cardiac Fabry's disease. To definitively exclude Fabry's disease, however, endomyocardial biopsy is required.