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Pericardial constriction: uncommon patterns

Constrictive pericarditis can be defined as a syndrome (or syndromes) resulting from compression of the heart caused by rigid, thickened, and frequently fused pericardial membranes. This syndrome was known about more than three centuries ago, but more recently its clinical spectrum has changed in two ways. Firstly, from the aetiologic point of view, there has been an increase in the number of cases of constrictive pericarditis secondary to chest radiation and cardiac surgery. In particular, cardiac surgery has emerged as an important cause of constrictive pericarditis, representing up to 18–29% of cases in some series,1,2 although its prevalence is only 0.2–0.3% following coronary artery bypass grafting or valvar surgery. Secondly, the haemodynamic spectrum has been expanded with other forms of constriction. In this paper we will first comment on the classical syndrome of chronic constrictive pericarditis, and then describe the other less known syndromes of cardiac constriction. Finally, some aetiological considerations will be discussed.

Chronic constrictive pericarditis is caused by a rigid, shell-like pericardial scar that restricts ventricular filling to earlier diastole. The clinical picture includes chronic fatigue and dyspnoea, neck vein distension with a brisk diastolic collapse (“y”) of the jugular venous pulse, pericardial knock, enlarged liver, ascites, peripheral oedema, and pleural effusion. Arterial pulsus paradoxus is usually absent. Atrial fibrillation is present in half of the patients. Constrictive pericarditis should be suspected in all patients with findings suggestive of right heart failure or ascites; diagnosis is usually not difficult provided there is an adequate index of suspicion. Diagnosis should be based on a triad of: a suggestive clinical syndrome; demonstration of …