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: Pharmacology
[{'content': 'Nitrates decrease myocardial oxygen consumption by all of the following mechanisms except - \nSelect and explain. \nA. By increasing the left ventricular end diastolic pressure, B. By direct reduction of oxygen consumption of the myocardial cell, C. By dilation of the capacitance vessels, D. By decreasing the size of hea', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., By increasing the left ventricular end diastolic pressure o Nitratets dilate veins (capacitance) vessels and decrease venous return (preload)o This results in decreased end diastolic pressure and left ventricular size (not increased), which ultimately leads to decreased oxygen consumption.", 'role': 'assistant'}]