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': 'A 58-year-old man is undergoing cardiac catheterization for evaluation of chest pain symptoms. He is worried about the risks, and as part of obtaining informed consent, you advise him about the risks and benefits of the procedure. Which of the following aspects of angiography is true? \nSelect and explain. \nA. it is contraindicated in the presence of cyanosis, B. it is considered noninvasive, C. it is generally performed with cardiopulmonary bypass, D. it may cause renal failure', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Contrast media used in cardiac catheterization may result in renal impairment. The group at highest risk includes diabetics with renal disease and those with preexisting renal failure. Good hydration is essential. Other manifestations of contrast media include nausea and vomiting (common), and anaphylactoid reactions characterized by low-grade fever, hives, itching, angioedema, bronchospasm, and even shock. Side effects are reduced with the use of new low osmolality contrast media.', 'role': 'assistant'}]