Intrapericardial "negative" cannon waves during atrioventricular dissociation in large pericardial effusion

Interpretation of cardiac pathophysiology from pressure waveform analysis: pericardial compressive hemodynamics, Part II

Constrictive physiology characteristically alters atrial and ventricular waveforms. Normal pressure and flow responses to inspiration are blocked or reversed. The impairment of early diastolic filling is the common feature of restrictive myocardial, as well as diseased pericardial, processes. Low pressure tamponade can limit cardiac output, but may be difficult to detect by clinical signs alone. Examination of the pressure waveforms may provide clues to the diagnosis of constrictive physiology in these patients.