Cardiac tamponade Cardiac tamponade is a clinical diagnosis with key physical (elevated venous pressure, pulsus paradoxus, hypotension) and echocardiographic (chamber collapses, abnormal venous flows, exaggerated respiratory variation in venous and cardiac flows, and vena caval plethora) findings. Echocardiographic findings suggestive of pericardial tamponade include: inferior vena cava (IVC) plethora, diastolic blunting of hepatic vein forward flow, respiratory inflow variation across the trisc