Congenital Absence of the Left Pericardium

A case of complete absence of the left pericardium, suspected from plain chest x-rays and proved by diagnostic left pneumothorax, has been reported. The significance of the pericardium in relation to cardiac function is discussed. Because absence of the left pericardium is a benign and relatively asymptomatic anomaly that usually requires no treatment, it behooves the clinician and radiologist to become cognizant of its presence.