Alström syndrome: cardiac magnetic resonance findings

Abstract

Background: Alström Syndrome (ALMS) is an extremely rare multiorgan disease caused by mutations in ALMS1. Dilated cardiomyopathy (DCM) is a common finding but only one series has been investigated by Cardiac Magnetic Resonance (CMR).

Methods: Eight genetically proven ALMS patients (ages 11-41) underwent CMR performed by standard cine steady state, T1, T2 and late gadolinium enhancement (LGE) sequences. Ejection fraction (EF), Diastolic Volume (EDV) and Systolic Volume normalized for body surface area (ESV), and mass indices were determined, as well as EDV/Mass ratio, an index expressing the adequacy of cardiac mass to heart volume. Regional fibrosis was assessed by LGE; diffuse fibrosis was measured by a TI scout sequence acquired at 5, 10 and 15 min after gadolinium by comparing inversion time values (TI) at null time in ALMS and control group.

Results: In one patient severe DCM was present with diffuse LGE. There were seven cases without clinical DCM. In these patients, EF was at lower normal limits or slightly reduced and ESV index increased; six patients had decreased mass index and EDV/Mass ratio. Mild regional non ischemic fibrosis was detected by LGE in three cases; diffuse fibrosis was observed in all cases, as demonstrated by shorter TI values in ALMS in comparison with controls (5 min: 152 ± 12 vs 186 ± 16, p 0.0002; 10 min: 175 ± 8 vs 204 ± 18, p 0.0012; 15 min: 193 ± 9 vs 224 ± 16, p 0.0002).

Conclusions: Cardiac involvement in ALMS is characterized by progressive DCM, associated with systolic dysfunction, myocardial fibrosis and reduced myocardial mass.

Keywords: ALMS1; Alström Syndrome; Cardiac Magnetic Resonance; Dilated cardiomyopathy; Fibrosis.