Pulse-wave Doppler distinguishes between constrictive pericarditis and chronic obstructive pulmonary disease

In patients with chronic obstructive pulmonary disease (COPD) the pulse-wave Doppler echocardiogram shows pronounced respiratory variation in superior vena caval (SVC) blood flow velocity (red arrows, panel A), which is not seen in constrictive pericarditis. In contrast, the mitral flow velocity (panel B) shows a similar respiratory variation (E wave, black arrows) in COPD and constrictive pericarditis. Recording SVC blood flow velocity is therefore a simple way to distinguish pulsus paradoxus due to constrictive pericarditis from that due to COPD.