P313Echocardiographic findings in cardiac sodium channel alpha-subunit gene mutation carriers.


    loading  Checking for direct PDF access through Ovid

Abstract

Background and aims: Mutations in the human cardiac sodium channel alpha-subunit gene (SCN5A) are involved in the pathophysiology of cardiac arrhythmias (Brugada syndrome (BS), Long QT syndrome (LQTS), cardiac conduction defects and idiopathic ventricular fibrillation), cardiomyopathies (dilated cardiomyopathy (DCM) and left ventricular non-compaction (LVNC) and other cardiac structural abnormalities. We aim to evaluate echocardiographic findings in carriers of SCN5A variants.Methods: Sequencing of SCN5A gene was performed in 103 patients diagnosed with BS (93.89%), LQTS (8. 8%) and cardiac arrest or ventricular arrhythmias in (3. 3%). SCN5A mutations/variants (3 families G1743R and 1 family each R27H, S524Y, R620H, V728I, E901K, E1032K, E1151stop and N1443S) were identified in 11 unrelated probands after excluding known polymorphisms. Echocardiographic findings from both probands and relatives from these 11 families were analysed. Echocardiograms from carriers (34. 65%) and non-carriers (18.35%) were compared.Results: 52 individuals (ind.) from 11 different families (mean 4.7 ind. per family) comprised the study population. Reason for SCN5A study was BS in 9 families (39 ind.), cardiac arrest in 1 (5 ind.) and ventricular arrhythmias in 1 (8 ind.). 12 (23%) ind. had echocardiographic abnormalities. 3 ind. had DCM (all from the same family, all carriers), 3 had left ventricular hypertrophy (from 3 different families, all carriers of SCN5A mutations, 2 with G1743R, 1 with E901K), 2 had left ventricular hypertrabeculation (both from same family and carriers of the same mutation S524Y), 1 had right ventricular dilatation (carrier of G1743R), 4 had significant valvular disease (3 aortic regurgitation and 1 tricuspid regurgitation, 3 of them carriers). 2 out of the 3 patients with aortic regurgitation had significant aortic and left ventricular dilatation (both carriers of R620H). 1 non-carrier had subaortic membrane and another non-carrier had anterior scar from an old myocardial infarction. 10 (26%) of carriers had echocardiographic abnormalities versus 2 (11%) non-carriers (p=0.1).Conclusions: Echocardiographic abnormalities seems to be particularly frequent in SCN5A carriers. Chamber dilatation, left venticular hypertrophy, left ventricular non-compaction and valvular disease have been demonstrated in our series. Larger and multicentre registries are needed to appropriately address this observation.

    loading  Loading Related Articles