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': 'Indication for aoic stenting is: March 2008 \nSelect and explain. \nA. Acute aoic occlusion, B. Aoic dissection, C. Rheumatic aoitis, D. Tetralogy of fallot', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. B: Aoic dissection Indications for Aoic stenting: Abdominal aoic aneurysm -Stent are available for patients with descending thoracic aoic aneurysms that are at least 2 Times greater than the adjacent aoa. Fuhermore, sufficient aoa of normal dimensions must be present on either side of the aneurysm (so-called landing zones) for the stent graft to adhere to the aoic walls. Focal penetrating ulcer: Patients with focal penetrating ulcers in their thoracic aoa are another group in which stent may prove beneficial because these patients have defined, limited areas of their thoracic aoa where a loss in the integrity of the endothelium leads to potentially life-threatening rupture. Aoic dissection', 'role': 'assistant'}]