A 42-year-old man comes to the emergency department due to fatigue, chest pain, and shortness of breath for the past 5 days. He has had difficulty falling asleep at night due to chest discomfort. The patient had a "bad case of the flu" 3 weeks ago and still has a persistent cough. He is otherwise healthy and has no other medical problems. He has a 20-pack-year smoking history and drinks 3 or 4 beers on weekends.
Blood pressure is 92/54 mm Hg and pulse is 112/min. Blood pressure decreases to 75/42 mm Hg during inspiration. Jugular venous pressure is estimated at 16 cm H₂O. There are minimal crackles present at both lung bases. Heart sounds are faint on cardiac auscultation. Lower extremities are cool with feeble pulses.
Chest x-ray is shown in the exhibit.
An echocardiogram in this patient would most likely show which of the following?

Question

A 42-year-old man comes to the emergency department due to fatigue, chest pain, and shortness of breath for the past 5 days. He has had difficulty falling asleep at night due to chest discomfort. The patient had a "bad case of the flu" 3 weeks ago and still has a persistent cough. He is otherwise healthy and has no other medical problems. He has a 20-pack-year smoking history and drinks 3 or 4 beers on weekends.
Blood pressure is 92/54 mm Hg and pulse is 112/min. Blood pressure decreases to 75/42 mm Hg during inspiration. Jugular venous pressure is estimated at 16 cm H₂O. There are minimal crackles present at both lung bases. Heart sounds are faint on cardiac auscultation. Lower extremities are cool with feeble pulses.
Chest x-ray is shown in the exhibit.

An echocardiogram in this patient would most likely show which of the following?

Quizplus · Accepted Answer

This patient's clinical presentation is consistent with viral pericarditis complicated by pericardial effusion and subacute cardiac tamponade. He has many of the classic clinical features of cardiac tamponade (including muffled heart sounds, hypotension with pulsus paradoxus, and elevated jugular venous pressure), and chest x-ray reveals classic "water bottle" heart indicating pericardial effusion. Transthoracic echocardiogram is useful for determining the size of the pericardial effusion and for identifying early signs of cardiac tamponade before overt hemodynamic collapse occurs. Accumulation of fluid in the pericardial cavity leads to an increase in intrapericardial pressure, and collapse of right-sided cardiac chambers occurs when the pressure within these cardiac chambers is exceeded. The right atrium has the lowest pressure of all cardiac chambers; therefore, right atrial collapse during end diastole is the earliest and most sensitive sign of cardiac tamponade. Right ventricular diastolic collapse is less sensitive than right atrial diastolic collapse, but is highly specific for the presence of cardiac tamponade. right atrial collapse (Choice A) Dynamic left ventricular outflow obstruction is seen in hypertrophic cardiomyopathy, for which pulsus paradoxus is not an expected finding. (Choice B) Global left ventricular hypokinesis is seen in patients with idiopathic cardiomyopathy, and can also occur in acute or subacute viral myocarditis. However, this patient has minimal pulmonary crackles, muffled heart sounds, and pulsus paradoxus, suggesting cardiac tamponade. The left ventricle is usually hyperkinetic in patients with cardiac tamponade. (Choice C) The left ventricle is more muscular and has higher cavity pressure than the right-sided heart chambers; as a result, left ventricular chamber collapse is seen in only a minority of patients with cardiac tamponade. When present, the finding is highly specific for tamponade. (Choice E) Right ventricular dilation and free wall hypokinesia with sparing of the apex (McConnell sign) can occur in patients with acute pulmonary embolism, with one study demonstrating 77% sensitivity and 94% specificity. Acute pulmonary embolism is less likely in this patient given the muffled heart sounds and "water bottle" sign on chest x-ray. McConnell sign Educational objective: Right atrial collapse during end diastole is the earliest and most sensitive echocardiographic sign of cardiac tamponade. Right ventricular diastolic collapse is less sensitive than right atrial diastolic collapse but is highly specific for cardiac tamponade. __________ References: Frequency and significance of chamber collapses during cardiac tamponade. (http://www.ncbi.nlm.nih.gov/pubmed/2330872) Hydrodynamic compression of the right atrium: a new echocardiographic sign of cardiac tamponade. (http://www.ncbi.nlm.nih.gov/pubmed/6861307)

A 42-Year-Old Man Comes to the Emergency Department Due to Fatigue