[Differential characteristics of primary acute pericarditis and severe pericardial effusion without tamponade]

The aim or our study was to evaluate the main clinical and etiological features or primary acute pericarditis with severe pericardial effusion without cardiac tamponade. Our experience included 35 patients with this problem diagnosed in the last 5 years. Patients with a previous potential etiology for acute pericarditis were excluded. The diagnostic protocol identified a specific etiology in 20% of patients, the most frequent being idiopathic forms. Patients with severe pericardial effusion without cardiac tamponade who had a favourable clinical outcome on nonsteroidal antiinflammatory drugs therapy presented a lower proportion of specific etiology than those with a poor response to this therapy (8% versus 45%; p = 0.03). An exhaustive etiological investigation, including diagnostic pericardiocentesis should be reserved for these patients with unfavourable response to antiinflammatory drug therapy.