Nontraumatic Pericardiophrenic Defect with Tamponade

A 2-year-old boy with multiple congenital anomalies, including bilateral club feet, arthrogryposis, and multilevel aortic coarctation and aneurysms, presented with acute abdominal pain, vomiting, abdominal distention, and lethargy. An unusual intraluminal air collection projecting over the left heart was seen on the chest radiograph. Echocardiography showed a structurally normal heart with a small concentric pericardial effusion and an echogenic mass posterior to the left ventricle (Fig. 1). There were echo-free spaces and cavitations evident within the mass. In addition, the left atrium was compressed, and there was respiratory variability of mitral valve inflow seen on spectral Doppler echocardiography, which suggested borderline tamponade. Urgent computed tomography of the chest and abdomen confirmed the presence of dilated loops of bowel within the pericardial space (Fig. 2). On computed tomography, there was a diaphragmatic defect posterior to the left lobe of the liver, rather than anterior, as would be expected with a Morgagni hernia. Fig. 1 Four-chamber echocardiographic view shows concentric pericardial effusion with an echogenic mass posterior to the left ventricle. Fig. 2 An oblique coronal reconstruction of a computed tomogram shows the pericardial effusion with dilated loops of bowel within the pericardial space. The patient was subsequently taken to the operating room, where he was noted to have a dilated transverse colon and several loops of small intestine herniating through a diaphragmatic defect that was anterior and just to the left of the esophageal hiatus. Inspection of the bowel revealed no areas of frank ischemia or necrosis. The bowel was easily reduced through the diaphragmatic defect, and the defect was closed primarily with pledgeted sutures. In this patient, the diagnosis of distal aortic coarctation with multiple regions of aortic narrowing in combination with aortic aneurysms was suspected antenatally. At several days of age, he underwent diagnostic cardiac catheterization, which confirmed severe coarctation of the upper abdominal aorta just below the level of the diaphragm, with multiple aneurysmal dilations distal to the coarctation. At 3 weeks of age, he underwent an uncomplicated interventional cardiac catheterization, during which 5 overlapping intravascular stents were placed in the abdominal aorta. The most proximal stent was in the distal thoracic aorta at the level of the diaphragm.