Differentiation of tricuspid regurgitation from constrictive pericarditis: Novel criteria for diagnosis in the cardiac catheterisation laboratory

Background: Severe tricuspid regurgitation, constrictive pericarditis and restrictive cardiomyopathy can all present with signs and symptoms of right heart failure and similar haemodynamic findings of elevation and equalisation of diastolic pressures at catheterisation. Although catheterisation findings of enhancement of ventricular interaction are a reliable parameter to distinguish constrictive pericarditis from restrictive cardiomyopathy, this also may be present in severe tricuspid regurgitation. Objective: To identify unique haemodynamic parameters that differentiate severe tricuspid regurgitation from constrictive pericarditis. Methods: Haemodynamic findings from simultaneous right and left heart catheterisation of 14 patients (age 59 years; men 71%) with documented severe tricuspid regurgitation (group I) were compared with those of 14 patients with surgically proven constrictive pericarditis (group II). Results: Findings of elevated right atrial pressure, early rapid ventricular filling and expiratory equalisation of ventricular diastolic pressures were similar in both groups. Ventricular interdependence, assessed by interaction of left ventricular (LV) and right ventricular (RV) systolic pressures, was also present in both groups. Relative changes in LV and RV diastolic pressures during respiration reliably distinguished group I from group II. During inspiration, the difference between the LV and RV diastolic pressures widened in group I but narrowed in group II. The height and slope of the early rapid filling wave in RV pressure trace was accentuated during inspiration in group I but did not change in group II. Conclusions: The haemodynamic findings at cardiac catheterisation in patients with severe, symptomatic tricuspid regurgitation are similar to those of constrictive pericarditis. Careful analysis of the relationship of the LV and RV diastolic pressures during respiration can help differentiate the two entities.