Transient constrictive pericarditis: an elusive diagnosis.

Constrictive pericarditis (CP) is caused by reduction in the elasticity of the pericardium resulting in impaired diastolic filling of the heart. All types of CP were thought to be irreversible in the past. This led to a belief that all patients with CP should undergo pericardiectomy. However, at present, it is well established that selected patients can be treated without pericardiectomy, leading to the concept of transient CP. Clinical improvement can be spontaneous or accomplished with empirical medical therapy administered for several months. As for chronic form, transient CP may not be recognized due to the difficulty in establishing the diagnosis because of the absence of any single method that is 100% sensitive and specific. It is worth considering the possibility of transient type when constrictive physiology is detected by noninvasive methods because correct diagnosis may prevent the inflamed pericardium from becoming the chronic fibrotic type that can be associated with more serious consequences including pericardiectomy.