IDIOPATHIC ENLARGEMENT OF RIGHT ATRIUM - REPORT OF 4 CASES

The case summaries of 4 patients with idiopathic enlargement of the right atrium are reported, 1 of whom had a giant diverticulum of the atrium requiring surgical resection. The reports of 8 similar patients have been clearly documented in the literature. These patients are usually asymptomatic, and attention is drawn to this condition by an abnormal cardiac silhouette on the roentgenogram of the chest. Atrial fibrillation is a frequent complication. Although usually a benign condition, idiopathic right atrial enlargement can lead to intrapericardial compression, venous congestion and spontaneous intra-atrial thrombus formation. Pulmonary embolization is a potential complication, but has not yet been reported to occur. Surgical resection is indicated in the presence of marked right atrial enlargement complicated by atrial fibrillation, venous congestion, evident thrombus formation, or signs of pulmonary embolization. © 1969.