Q; 42 year old female is admitted to ICU due to Mobitz type II second degree AV block. Patient initially presented to ED with cough and fever, but admitted to ICU after astute nurse in ED noted possible AV block on monitor, later confirmed by EKG. You were unable to identify any cause of AV block from her present or family history, list of medications or physical examination. Name few disease processes which should be of your concern?


Answer:

• Amyloidosis 
• Sarcoidosis
• Lyme disease 
• Endocarditis with abscess formation
• Hyperkalemia 
• Hypervagotonia

It may be of interest to know that, in patients under 60 years of age who present with otherwise unexplained or previously undetected heart block, cardiac sarcoidosis has been identified in up to 35 percent of patients.


References:

1. Nery PB, Beanlands RS, Nair GM, et al. Atrioventricular block as the initial manifestation of cardiac sarcoidosis in middle-aged adults. J Cardiovasc Electrophysiol 2014; 25:875. 

2. Takaya Y, Kusano KF, Nakamura K, Ito H. Outcomes in patients with high-degree atrioventricular block as the initial manifestation of cardiac sarcoidosis. Am J Cardiol 2015; 115:505. 

Birnie DH, Sauer WH, Bogun F, et al. HRS expert consensus statement on the diagnosis and management of arrhythmias associated with cardiac sarcoidosis. Heart Rhythm 2014; 11:1305.