Bilateral wandering inferior pulmonary veins

Clinical History

50 y/o woman. No medical history of interest.
Chest X-ray performed because of a year-long retrosternal intermittent, non-irradiated pain.

Imaging Findings

- Chest X-ray: Tubular curved opacities over bilateral lower pulmonary zones.

- Enhanced chest CT: Both inferior pulmonary veins are enlarged and follow an anomalous, tortuous peripheral course. The lower left pulmonary vein drainage includes part of the lingula. All the pulmonary veins drain into the left atrial appendage, with no abnormalities in location and number of ostia. Neither airway nor arterial tree show any pathology.

Discussion

The typical anatomy (found in 70% of patients) [1] consists of four pulmonary veins, two draining each lung. The right superior pulmonary vein drains the upper and middle lobes; the left superior vein drains the lingula and left upper lobe and both inferior veins drain each lower lobe. They course in the intersegmental septa (unlike the pulmonary arteries) and drain separately into the left atrial appendage, passing anterior and inferior to the pulmonary arteries.

Meandering pulmonary vein was first described by Goodman et al (1972) [2]. It consists of an abnormal course of a pulmonary vein, following a peripheral and tortuous route, with a subsequent normal drainage into the left atrial appendage. It doesn't associate any other vascular, cardiac or lung anomalies.

It is considered an anatomical variant, included into the group of congenital anomalies of the pulmonary venous drainage [3].
There are very few case reports of this entity, and only one [4] describing a bilateral form.

It is usually an incidental finding on an imaging test performed for other reasons. Patients remain asymptomatic.

In chest X-ray we can see a curved vascular shadow with a peripheral path, which may be confused with the appearance of a Scimitar syndrome when it courses through the right lower lobe, along the right cardiac border [5]. When bilateral, as in our case, we will see this over both hemithoraces.

Enhanced CT is the technique that will allow us to make the diagnosis in most of cases. We can see the anomalous vein as a dilated, curved vascular structure with a peripheral course and also demonstrate its normal drainage into the left atrial appendage and the absence of other vascular or parenchymal anomalies.

Bilateral meandering inferior pulmonary veins are considered an anatomical variant with no associated complications [6] that doesn't require any follow-up.

This is a rarely described entity with the bilateral form being even rarer. In the literature there are a few old case reports lacking high resolution images with up-to date imaging techniques. Familiarity with this rare anatomic variant of inferior pulmonary veins will allow Radiologists to reliably distinguish it from other congenital vascular diseases that might require further investigation with additional imaging.

Differential Diagnosis List

Final Diagnosis

Bilateral meandering inferior pulmonary veins

URL:	https://www.eurorad.org/case/13810
DOI:	10.1594/EURORAD/CASE.13810
ISSN:	1563-4086