DIAGNOSTIC ASPECTS

Pericardial syndromes

The diagnosis of acute pericarditis relies on clinical findings, ECG changes, and echocardiography (table 1).^2,3 Chronic pericardial inflammation includes effusive, adhesive, and constrictive forms, lasting three months or more. Recurrent pericarditis may be intermittent (symptom-free interval without treatment) or incessant (discontinuation of anti-inflammatory treatment always ensures a relapse).

Pericardial effusion occurs as transudate (hydropericardium), exudate, pyopericardium or haemopericardium, or a mixture of these. Large effusions generally indicate more serious disease and are common with neoplasia, tuberculosis, hypercholesterolaemia, uraemic pericarditis, myxoedema, and parasitoses.^2,4 Patients can be asymptomatic if effusion develops slowly. Many pregnant women develop a minimal to moderate clinically silent hydropericardium by the third trimester. Fetal pericardial fluid can be detected by echocardiography after 20 weeks’ gestation and is normally 2 mm or less in depth. More fluid should raise questions of hydrops fetalis, Rh disease, hypoalbuminaemia, and immunopathy or maternally transmitted mycoplasmal or other infections, and neoplasia.³

Echocardiography reveals the size of effusions: (1) small (echo-free space in diastole < 10 mm); (2) moderate (at least ⩾ 10 mm posteriorly); (3) large (⩾ 20 mm); or (4) very large (⩾ 20 mm with compression of the heart).² Presence of fibrin, clot, tumour, air, and calcium can also be detected. Pericardial effusion must be differentiated from pleural fluid, ascites, atelectasis, or epicardial fat. Transoesophageal echocardiography is useful in loculated pericardial effusions, intrapericardial clots, metastases, and pericardial thickening. …