Should I be concerned about a pulmonary artery measuring 4.2 cm?

My CT chest with contrast report, pulmonary arteries within the pulmonary trunk measuring up to 4.2 cm in diameter bifurcation. Is this something I should be concerned with?

Submitted by Sandra from Texas on 04/08/2017

The main pulmonary artery before bifurcation usually measures approximately 3 cm or less, or less than the corresponding size of the thoracic aorta at the same level. The question submitted did not provide information regarding the reason of the CT scan.

There are various cause of enlargement of the main pulmonary artery.

(1). From the heart, such as heart failure (due to reduction in the squeeze of the heart, or increase in stiffness of the heart); communication between the left side right side of the heart, leading to increase in flow through the pulmonary artery; valvular regurgitation (leaking) … to name a few causes

(2). From the lungs, such as underlying chronic lung disease (emphysema); and various causes leading to pulmonary hypertension

(3). Other cause, such as sleep apnea, could also cause a mild dilation of the pulmonary artery.

One should discuss the findings of the enlarged pulmonary artery with the ordering physician and / or the physician who interpreted the report, to confirm that there is actual enlargement of the pulmonary artery.

As this is a CT scan, other information including the lungs fields, should have been imaged. In addition, if the CT scan is performed with contrast, there could be other clues to explain why the pulmonary artery is enlarged.