TEMPORAL TRENDS IN LEFT ATRIAL FUNCTION IN PATIENTS WITH FABRY DISEASE

Abstract

Fabry disease is a lysosomal storage disorder that results in deposition of glycolipids in various tissues including the left atrium (LA). Reduced LA function in patients with Fabry disease may represent an early sign of disease progression prior to the development of left ventricular hypertrophy (LVH). However, long-term trends in LA function over time and the temporal relationship between LA function and LVH have not been previously described. We retrospectively assessed the trends in LA function—measured by the LA emptying fraction (LAEF)—in 15 patients with Fabry disease followed at a tertiary care clinic who underwent annual surveillance echocardiography over a 10-year period. Trends were analyzed by linear regression and the estimated LAEF at the beginning and end of the study period were compared to reference standards from a normal healthy population. Patients with reduced LAEF were compared to those with preserved LAEF with respect to clinical and echo characteristics.Of the 15 patients included in the study, 10 (67%) were female and the median age was 42 years (range 26-65 years). Thirteen patients (87%) received enzyme replacement therapy (ERT): 10 (67%) initiated therapy within one year of the first echo. LVH was found in nine patients (60%) on the first echo and 11 patients (73%) on the final echo. LAEF was reduced in five patients (33%): one improved from reduced to normal, two remained reduced, and two progressed from normal to reduced. Notably, reduced LAEF was only found in patients with established LVH who were receiving ERT. Reduced LA function occurred in one-third of patients with Fabry disease in our cohort and was limited to patients who already developed LVH and were receiving ERT. Our findings suggest that LVH, rather than an inherent atrial myopathy, is the predominant cause of LA impairment in patients with Fabry disease.