Q- A 55-year-old man underwent internal fixation of a 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 (LBBB)
C- Septic shock
D- Hypertrophic cardiomyopathy
E- Pericardial effusion
Answer:
- The patient presents with substernal chest pain, shortness of breath, and signs of cardiac tamponade, including tachycardia, elevated blood pressure, and crackles on both lung bases.
- The harsh systolic murmur across the precordium is indicative of a pericardial friction rub, a classic finding in pericardial effusion.
- The delayed precordial transition on the ECG is consistent with the presence of a pericardial effusion.
- Given the recent history of trauma and surgery, the patient is at risk of developing a hemorrhagic pericardial effusion, which can lead to cardiac tamponade.
- Acute myocardial infarction is less likely as the patient has no significant ECG changes and normal cardiac enzymes. Left bundle branch block (LBBB) would typically present with specific ECG changes. Septic shock typically presents with hypotension and signs of systemic infection, which are not prominent in this case. Hypertrophic cardiomyopathy is less likely given the acute presentation and absence of characteristic findings.
The correct answer is E
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