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Published on: March 12, 2013
Pathogenic Variants in NKX2-5 Associated With Familial Atrial Septal Defect and Conduction System Disease
Varun Srivatsav1, Andrea Guerin2, Hoshiar Abdollah1
1Division of Cardiology, Department of Medicine, Queen's University, Kingston, Ontario, Canada.
Background:
Most atrial septal defects (ASDs) occur sporadically, but familial cases can occur and carry a 10% risk of transmission to offspring.
Case Summary:
We describe a 3-generation family with autosomal dominant secundum ASD and conduction system disease related to a novel NKX2-5 variant (c.300del; p.Asp101Thrfs∗75). The index patient, a 58-year-old woman with prior ASD repair and mitral valve replacement, presented with chronotropic incompetence, atrial fibrillation, left bundle branch block, and prolonged pauses, leading to pacemaker implantation. Her mother had an ASD, atrial fibrillation, left bundle branch block, and pulmonary arterial hypertension. The proband's daughter also had an ASD. Genetic testing revealed a novel NKX2-5 pathogenic variant in all 3 patients.
Review Summary:
The combination of an ASD and conduction system disease represents the most common phenotype in patients with pathogenic NKX2-5 variants.
Take-Home Message:
A thorough family history and genetic testing are needed when evaluating patients with ASD and concurrent conduction system abnormalities.
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