[Unilateral left agenesis of the pericardium. Contribution of cardiac imaging].

The authors report a case of congenital absence of the left pericardium in a pauci-symptomatic young woman. Indirect signs in favour of this diagnosis were elicited on chest X-ray (levoposition of the heart, convex left heart border). An associated congenital heart lesion was excluded by Doppler echocardiography. Computed tomography and MRI showed the right pericardium to be present but the left pericardium (not always visible in normal subjects) and the pre-aortic recess (present in all normal subjects) were absent. Abnormal presence of lung tissue between the aorta and pulmonary artery, and also between the pulmonary artery and left auricle was, however, confirmed. Nevertheless, these investigations did not enable the authors to define the exact extent of the pericardial defect. Finally, the indirect signs of levocardioposition were the main diagnostic markers of congenital absence of the left pericardium which did not require surgery in this particular case.