An 84-year-old man was brought to the emergency department as he complained about high blood pressure and acute onset of diffuse facial paresthesia. Examination A series of ECGs revealed a changing conduction rhythm from new first-degree atrioventricular (AV) block with left bundle branch block (LBBB), to first-degree AV block without LBBB. Clinical features Symptomatic bradycardia The cardiologists identified a characteristic, evolving conduction block arrhythmia. Sclerotic fibro-fatty degeneration of the Bundle of His and Purkinje fibers, increasing AV delay with age.

Similar presentation noted post 40 years age. What is this rare conduction disorder called? Source: The American journal of emergency medicine The answer is posted in the comment section below!