Fabry Disease with Pacemaker Implantation as the Initial Event

Prevalence and predictors of bradyarrhythmias requiring Permanent Pacing in patients with Anderson-Fabry disease

Bradyarrhythmias are an established red flag for storage cardiac conditions including Anderson-Fabry disease (AFD). The prevalence of bradyarrhythmias requiring a pacemaker (PM) and their timing in AFD is unresolved. We evaluated prevalence and predictors of PM requirement in a large AFD cohort, investigating the occurrence of bradyarrhythmias as initial versus late manifestation. We retrospectively evaluated 82 consecutive AFD patients referred to our multidisciplinary referral centre from 1994 to 2020 with a median follow up of 6.9 years, identifying those requiring pacing. Univariable analysis was performed to identify cardiac features associated with PM implantantion. Five of 82 (6%) AFD patients required PM implantation (5/39, i.e. 13% of those with cardiac involvement), always in the context of advanced cardiomyopathy. In none, bradyarrhythmias were the presenting feature. Indications included sick sinus syndrome in 3 patients, advanced atrio-ventricular block in 2 patients. QRS prolongation during follow up strongly correlated with the onset of bradyarrhythmias. Severe bradyarrhythmias are relatively frequent in patients with AFD cardiomyopathy, but do not represent a mode of presentation, occurring late in the disease course and always in the context of advanced cardiac involvement. Monitoring QRS variations over time may help to identify patients requiring pacing. This article is protected by copyright. All rights reserved.

A morphological classification of the fat particles found in the urinary sediment of patients with Fabry disease

OBJECTIVES

The search in the urinary sediment (U-sed) of fat particles with peculiar morphology is a simple and inexpensive tool for the diagnosis of Fabry disease (FD) nephropathy. In this study we investigated the morphology of a high number of such fat particles with the aim to obtain a morphological classification to be used for their identification.

METHODS

Study of the morphology of fat particles in the U-sed of a cohort of FD patients using: bright field plus phase contrast microscopy (BF + PC), polarized light microscopy (POL), and transmission electron microscopy (TEM). Comparison of these results with those obtained for the fat particles seen in the U-sed of a control group (CG) of patients with non-FD glomerulopathies.

RESULTS

FD: 18 U-sed from six patients (three samples/patient) were prospectively investigated and 506 fat particles identified. With BF + PC, these were classified in eight morphological categories (seven of which were confirmed by TEM), and with POL in 10 others. CG: eight U-sed from eight patients were investigated and 281 fat particles identified. These fell into four BF + PC morphological categories and into eight POL categories. While some categories were significantly more frequent in FD others were more frequent in the CG.

CONCLUSIONS

Our study demonstrates that 1. The morphology of fat particles found in the U-sed of FD patients is much wider and complex than that described so far 2. Several significant differences exist in the morphology of such fat particles between FD and CG patients.