Naxos syndrome is associated with which form of cardiomyopathy?

Naxos syndrome is associated with which form of cardiomyopathy?

• A. Hypertrophic cardiomyopathy
• B. Dilated cardiomyopathy (DCM)
• C. Restrictive cardiomyopathy
• D. Arrhythmogenic right ventricular cardiomyopathy

Answer: (B)

Naxos syndrome is a form of arrhythmogenic cardiomyopathy, specifically affecting the right ventricle. It arises from mutations in desmosomal proteins (most classically plakoglobin/JUP) and presents with woolly hair and palmoplantar keratoderma along with fibrofatty replacement of the right ventricular myocardium. This disease leads to ventricular arrhythmias and a risk of sudden death, which is the hallmark feature of ARVC. The other cardiomyopathy types don’t fit this pattern. Hypertrophic cardiomyopathy involves thickened heart muscle, not the fibrofatty degeneration of the right ventricle. Restrictive cardiomyopathy is characterized by stiff ventricles with diastolic dysfunction. Dilated cardiomyopathy features dilation and systolic dysfunction, typically without the characteristic skin findings or right-ventricular fibrofatty replacement. (There is a related condition, Carvajal syndrome, due to desmoplakin mutations, which can have left-sided predominant disease, but classic Naxos is ARVC.)

Naxos syndrome is a form of arrhythmogenic cardiomyopathy, specifically affecting the right ventricle. It arises from mutations in desmosomal proteins (most classically plakoglobin/JUP) and presents with woolly hair and palmoplantar keratoderma along with fibrofatty replacement of the right ventricular myocardium. This disease leads to ventricular arrhythmias and a risk of sudden death, which is the hallmark feature of ARVC.

The other cardiomyopathy types don’t fit this pattern. Hypertrophic cardiomyopathy involves thickened heart muscle, not the fibrofatty degeneration of the right ventricle. Restrictive cardiomyopathy is characterized by stiff ventricles with diastolic dysfunction. Dilated cardiomyopathy features dilation and systolic dysfunction, typically without the characteristic skin findings or right-ventricular fibrofatty replacement. (There is a related condition, Carvajal syndrome, due to desmoplakin mutations, which can have left-sided predominant disease, but classic Naxos is ARVC.)