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: Pediatrics
[{'content': "Which one of the following congenital hea diseases has cyanosis without cardiomeglay and/ or congestive hea failure - \nSelect and explain. \nA. Transposition of great aeries, B. Fallot's tetralogy, C. Congenital mitral regurgitaion, D. Congenital pulmonary stenosis", 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Fallot's Tetralogy Cardiomegaly and CHF do not occur in Fallot's tetrology. No Cardiomegaly o First you should know the following facts : ? i) Pressure overload to ventricles causes concentric hyperophy without dilatation. ii) Volume overload to ventricles causes hyperophy with dilatation --> Eccentric hyperophy. o Due to pulmonary stenosis, there is pressure overload to right ventricle --> Concentric hyperophy of right ventricle without dilatation - No Cardiomegaly. No CHF o The VSD of TOF is always large enough to allow free exit to the right to left shunt. Since the right ventricle is effectively decompressed by the VSD, CHF never occurs in TOF.", 'role': 'assistant'}]