A 55 year-old man underwent internal fixation of fractured femur after a motorcar accident and massive bleeding 24 hours ago. He was stable after the surgery and his urine output was normal after he received intravenous fluids. Now he complains of substernal chest pain and shortness of breath. On examination, His temperature is 98.8 F, Pulse is 110/min, blood pressure is 160/100 mmHg and his respiratory rate is 24/min. There is no jugular vein distention. His extremities have established pulses bilaterally and good perfusion. Auscultation reveals harsh systolic murmur across the precordium and crackles on both lung bases. ECG shows sinus tachycardia with delayed precordial transition and no other changes. Laboratory tests including cardiac enzymes are all normal. What is the most likely diagnosis? A - Acute myocardial infarction B - Left bundle branch block C - Septic shock D - Hypertrophic cardiomyopathy E - Pericardial effusion Answer