The Prevalence of Fabry Disease Among Turkish Patients with Non-Obstructive Hypertrophic Cardiomyopathy: Insights from a Screening Study.

Aims: Fabry disease is an X-linked lysosomal storage disorder due to a deficiency of the α-galactosidase A enzyme. Cardiac involvement is present in over 60% of adult cases of Fabry disease. Hypertrophic cardiomyopathy without left ventricular outflow tract obstruction is the most common phenotype. The aim of the study was to screen adult patients with hypertrophic cardiomyopathy without left ventricular outflow tract.

Methods: A total of 80 patients between the ages of 18 and 65 years old, were referred to a tertiary center for trans-thoracic echocardiography for various clinical indications. They were investigated for the presence of idiopathic left ventricular hypertrophy without resting or dynamic left ventricular outflow tract obstruction. Plasma α-galactosidase A enzyme activity and α-galactosidase GLA gene mutations were investigated.

Results: The mean age was 41.5±12.7 years and 66.25% of patients were males. The mean echocardiographic parameters were as follows: left ventricular ejection fraction 60.7±7.4%, interventricular septum thickness 18.2±4.4 mm, left ventricular posterior wall 13.5±2.1 mm, left ventricular end-diastolic diameter 47.4±6.2 mm, left ventricular end-systolic diameter 27.8±6.5 mm, and left ventricular mass index 171.05±48.5 g/m². Hemizygous mutations associated with Fabry disease were detected in two male patients (2.50% of the screened population): NM_000169.2:c.334C>T(p.Arg112Cys), NM_000169.2:c.902G>A(p.Arg301Gln).

Conclusion: Fabry disease should be considered in the differential diagnosis in a highly selected patient population with unexplained left ventricular hypertrophy. The cardiologist may play an important role in the screening and diagnosis of the disease.