Severe pulmonary hypertension on CXR

Severe pulmonary hypertension on CXR

Severe pulmonary hypertension on CXR: X-Ray chest PA view showing features of severe pulmonary hypertension. There is mild cardiac enlargement with prominence of the right atrial contour (RA), which is extending more to the right than usual. Main pulmonary artery is prominent (MPA) and left pulmonary artery can be seen descending within the cardiac silhouette within the left cardiac border (starting behind the main pulmonary artery), but has not been annotated here. Right pulmonary artery is also dilated (RPA). End on view of a few pulmonary arteries are also seen. Presence of end on view of multiple pulmonary arterial branches would suggest a significant left to right shunt as the cause of pulmonary hypertension. In Eisenmenger syndrome, right atrial enlargement along with features of pulmonary hypertension would indicate a pre-tricuspid shunt as the cause (atrial septal defect). In atrial septal defect with Eisenmenger syndrome, the pulmonary arterial pressures can reach supra systemic levels. Suprasystemic pulmonary arterial pressures do not occur in ventricular septal defect or patent ductus arteriosus as the large post tricuspid communication equalizes the pressures on both sides.

Multiple fibrotic strands are seen in both lower zones, these being not typical of vascular marking. These could be a sequelae of previous recurrent respiratory infections which are common in persons with large left to right shunts. Recurrent respiratory infections are more common in post tricuspid shunts, more so in infancy.

Measurements of pulmonary artery size has been suggested for diagnosing pulmonary hypertension on chest X-ray, though echocardiography would be a more accurate method [1]. They suggested right descending pulmonary artery size more than 16 mm in PA view as indicating pulmonary hypertension. Left descending pulmonary artery size of more than 18 mm in lateral view was considered suggestive of pulmonary hypertension. Combining both measurements, they could obtain 98% accuracy in the diagnosis of pulmonary hypertension.

Updated on 3rd May 2020

Reference

1. Matthay RA, Schwarz MI, Ellis JH Jr, Steele PP, Siebert PE, Durrance JR, Levin DC. Pulmonary artery hypertension in chronic obstructive pulmonary disease: determination by chest radiography. Invest Radiol. 1981 Mar-Apr;16(2):95-100.