Background: Conventional cardiac catheterization criteria for the diagnosis of constrictive pericarditis (CP) rely on equalization of intracardiac pressures and have many recognized limitations. Recently, Doppler echocardiographic methods have been used to examine dynamic respiratory changes of increased ventricular interdependence and dissociation of intrathoracic and intracardiac pressures for the diagnosis of CP. These pathophysiological features may be best delineated by cardiac catheterization. Therefore, we studied the accuracy of these dynamic respiratory changes in left ventricular and right ventricular pressure for the diagnosis of CP at cardiac catheterization.
Methods and results: High-fidelity manometric catheters and respirometry were used to study 36 patients: 15 patients with surgically proven CP (group 1) and 21 patients with other causes of heart failure (group 2). Conventional cardiac catheterization variables used to establish the diagnosis of CP lacked sensitivity and specificity and failed to distinguish between these groups. However, the finding of discordance between right ventricular and left ventricular pressures during inspiration, a sign of increased ventricular interdependence, accurately distinguished patients in group 1 from those in group 2 (P < .05).
Conclusions: Examination of dynamic respiratory changes indicating increased ventricular interdependence may be helpful in the diagnosis of CP in the cardiac catheterization laboratory.