A person with mitral regurgitation and atrial fibrillation presents with syncope. On examination the person has a heart rate of 55. What is the most probable cause?
A. Digitalis toxicity
B. Incomplete heart block
C. Stroke
D. Subarachnoid Haemorrhage

Answer : Digitalis toxicity

It is probably a case of digitalis toxicity resulting in complete heart block.

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