Appearance of the normal pericardium on coronary MR angiograms.

We evaluated the appearance of the normal pericardium on breath-hold MR images used to visualize coronary arteries. A coronary MR angiogram was obtained in 23 subjects (17 healthy volunteers and six patients with no known pericardial disease) using a breath-hold K-space segmented gradient-recalled echo sequence with fat suppression. Each coronary MR angiographic study included imaging planes equivalent to the following echocardiographic planes: four-chamber view, vertical two-chamber view, and two short-axis views (at base and mid ventricular level). The average pericardial thickness was 1.7 mm (range, 1.5-2.0 mm), and an average length of 60 mm (range, 20-110 mm) of pericardium was visualized. A significantly longer portion of the pericardium was seen in the vertical two-chamber view and the basal short-axis view than in the two other views (P < .001). Normal anatomic variations and overlapping structures and image artifacts can alter the appearance of the pericardium. Breath-hold MR imaging techniques used for coronary MR angiography allow routine, time-efficient evaluation of large portions of the pericardium.