Asymptomatic Chronic Large Pericardial Effusions: To Drain or to Observe?

Pericardial effusions, especially large ones, have traditionally been regarded with concern by clinicians due to the sometimes unpredictable development of life-threatening cardiac tamponade. In the European Society of Cardiology Guidelines on pericardial diseases, the simplified algorithm for pericardial effusion triage and management recommends pericardial drainage in cases of cardiac tamponade and/or suspicion of bacterial or neoplastic etiology. In the presence of acute pericarditis, empiric anti-inflammatory treatment should be given, while when a specific indication known to be associated with pericardial effusion is found, then treatment of the underlying cause is indicated. Notably, the most challenging subgroup of patients includes those with large, asymptomatic, C-reactive-protein-negative, idiopathic effusions. In the latter subjects, pericardial drainage is proposed in cases of chronic effusions (lasting more than three months). However, this recommendation is based on scant data stemming from small-sized non-randomized studies. Nevertheless, recent evidence in a larger cohort of patients pointed out that a watchful waiting strategy is a safe option in terms of complication-free survival. This review summarizes the contemporary evidence on this challenging topic and provides recommendations for tailoring individual patient treatments.