Point-of-Care Diagnosis of Cardiac Tamponade Identified by the Flow Velocity Paradoxus

The presentation of cardiac tamponade is a spectrum from occult to extreme. The clinical history, physical exam, electrocardiogram, and radiographic findings of tamponade have poor sensitivities and even worse specificities. We use a clinical scenario to demonstrate how point-of-care cardiac ultrasound can diagnose impending cardiac tamponade in a clinically stable patient. The ultrasound finding we recommend is the flow velocity paradoxus, in which respiratory variation causes significant changes in transvalvular inflow velocities, which are exaggerated when tamponade is present. The management of a pericardial effusion depends on its physiologic effect, and point-of-care ultrasound directly measures that effect and expedites patient care.