Constrictive pericarditis.

Constrictive pericarditis (CP) is characterized by scarring and loss of elasticity of the pericardium, resulting in external impedance of cardiac filling. In the developed world, CP is most frequently encountered as a consequence of previous cardiac surgery, thoracic irradiation, viral or idiopathic causes. Tuberculosis still remains a common cause of CP in the developing world, immigrants from underdeveloped nations, and immunosuppressed patients. Clinical signs and symptoms of right heart failure coupled with risk factors for pericardial disease should raise suspicion for CP. Echocardiographic evaluation and often cardiac catheterization are essential components of accurate diagnosis of CP. Enhanced interventricular dependence, with respiratory variation in the ventricular pressures, and ventricular discordance are the pathophysiologic hallmarks of CP. Imaging findings such as increased pericardial thickness or pericardial calcification on computed tomography can be supportive, but are not necessary for the diagnosis of CP. Pericardiectomy remains the most effective therapy for symptomatic CP.