Summary

Pleural effusion is a common finding after coronary bypass graft surgery. Rarely, patients may develop loculated effusions, which may potentially lead to cardiac chamber compression. We report a rare case of loculated right pleural effusion (LRPE) that resulted in right atrial compression, leading to cardiac tamponade physiology, which resolved completely after emergent surgical drainage of the pleural effusion. This case underscores the need for early implementation of echocardiography in the postoperative management of hemodynamically unstable patients following cardiac surgery.