This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'Clinical finding in AV fistula is one of the following \nSelect and explain. \nA. Pericarditis, B. Sinus tachycardia, C. Cardiac arrhythmia, D. Hypothermia', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The mechanism behind bradycardia associated with Branham sign is likely similar to the reflex arc that occurs during the Bezold-Jarisch reflex. Presence of an AV fistula results in increased cardiac output because of low resistance across the AV shunt. Ref Davidson 23rd edition pg 467', 'role': 'assistant'}]