This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
[{'content': 'What is the most common cause of tricuspid regurgitation? \nSelect and explain. \nA. Coronary aery disease, B. Rheumatic hea disease, C. Dilatation of right ventricle, D. Endocarditis due to intravenous drug abuse', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Tricuspid regurgitation most commonly arise secondary to marked dilation of the tricuspid annulus from right ventricular enlargement due to pulmonary aery hypeension. Tricuspid regurgitation can also occur secondary to right ventricular enlargement from inferior wall MI, in the late stages of hea failure due to rheumatic or congenital hea disease with severe PA hypeension, as well as in ischemic and idiopathic dilated cardiomyopathies. Infarction of RV papillary muscles, tricuspid valve prolapse, carcinoid hea disease, endomyocardial fibrosis, radiation, infective endocarditis, and trauma can also produce TR. Ref: Harrisons Internal Medicine, 18th Edition, Chapter 237', 'role': 'assistant'}]