Andersen-Tawil Syndrome Presenting with Complete Heart Block

Area of Science:

• Neurology
• Cardiology
• Genetics

Background:

• Andersen-Tawil syndrome (ATS) is a rare autosomal dominant neuromuscular disorder.
• It is caused by mutations in the KCNJ2 gene.
• The classical phenotype includes periodic paralysis, cardiac conduction abnormalities, and dysmorphic features.

Observation:

• Cardiac involvement in ATS ranges from mild abnormalities to life-threatening events like ventricular tachyarrhythmias.
• This report details the first documented case of advanced atrioventricular (AV) block in a patient with ATS.
• Subtle dysmorphic features and predominant neurological symptoms can mask the cardiac manifestations of ATS.

Findings:

• Mutations in KCNJ2 gene are linked to Andersen-Tawil syndrome.
• Advanced atrioventricular (AV) block represents a severe cardiac manifestation of ATS.
• Clinical factors can delay the diagnosis of ATS, particularly when cardiac symptoms are not the primary presentation.

Implications:

• Recognizing advanced AV block as a potential manifestation of ATS is critical for timely intervention.
• Increased awareness of ATS's diverse clinical spectrum can improve diagnostic accuracy.
• Further research into KCNJ2 mutations and their cardiac effects may reveal new therapeutic targets for ATS.