10-19-2007, 04:26 AM
A 42-year-old woman with a history of active breast cancer presents with acutely worsening dyspnea. Physical exam reveals tachycardia, hypotension, elevated jugular venous pressure, and distant heart sounds. An EKG shows electrical alternans. Pulsus paradoxus is performed and is 20 mm Hg. A chest x-ray reveals a large cardiac silhouette. A two-dimensional echocardiogram confirms a large pericardial effusion with tamponade physiology. All the following are true concerning cardiac tamponade, except:
a) Pulsus paradoxus can be seen in other conditions, such as chronic obstructive pulmonary disease (COPD).
b) Cardiac catheterization will show diastolic equilibration of pressures within the heart.
c) The most specific echocardiographic finding of tamponade is LV collapse.
d) Mechanical ventilation with positive airway pressure should be avoided in patients with tamponade, because this further reduces cardiac output.
e) Electrical alternans is an EKG beat-to-beat change in the QRS axis secondary to swinging of the heart within the fluid-filled pericardium
a) Pulsus paradoxus can be seen in other conditions, such as chronic obstructive pulmonary disease (COPD).
b) Cardiac catheterization will show diastolic equilibration of pressures within the heart.
c) The most specific echocardiographic finding of tamponade is LV collapse.
d) Mechanical ventilation with positive airway pressure should be avoided in patients with tamponade, because this further reduces cardiac output.
e) Electrical alternans is an EKG beat-to-beat change in the QRS axis secondary to swinging of the heart within the fluid-filled pericardium