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: Surgery
Gangrene of intestine is seen in all the following conditions, except - 
Select and explain. 
A. Tricuspid Valve Endocarditis, B. Shock, C. Mesenteric Aery Thrombosis, D. Volvulus
A: Tricuspid Valve Endocarditis
Answer: A: Tricuspid Valve Endocarditis 
Explanation: Ans. is 'a' i.e., Tricuspid valve Endocarditis Tricuspid valve endocardilis would produce emboli, that would not be able to reach the intestine due to pulmonary filteration. They will be trapped in the pulmonary circulation and would not reach systemic circulation. Mesenteric aery thrombosis & volvulus would occlude the mesenteric vascular supply resulting in ischemia and gangrene of intestine. Shock causes non-occlusive ischemia & gangrene of intestine.