Keywords pulmonary vein varix - rare pulmonary vascular anomaly - pulmonary vein varix
Introduction
Pulmonary venous varix is a rare pulmonary vascular anomaly. It may be congenital
or acquired and is characterized by focal aneurysmal dilatation of the pulmonary vein.
Imaging appearances mimic pulmonary arteriovenous malformation (AVM) or pulmonary
mass. As the management strategies differ, it is important to accurately diagnose
the entity.
Case Report
A 34-year-old woman with symptoms of chest pain, shortness of breath, and dry cough
of 1 month duration and with a diagnosis of pulmonary AVM on contrast-enhanced computed
tomography (CECT) of the chest was referred to our institution for further evaluation
and management. The chest pain was nonspecific. Her dyspnea progressed from grade
1 to grade 2 modified Medical Research Council dyspnea scale with no orthopnea and
paroxysmal nocturnal dyspnea. Dry cough was associated with no diurnal or postural
variation. She reported having similar symptoms intermittently during 3 years prior
to presentation. On examination, the heart rate was 110 beats/min, respiratory rate
was 22/min, blood pressure was 110/70 mm Hg, and oxygen saturation was 98% on room
air. The laboratory workup showed anemia with low hemoglobin of 8.2 g/dL. Electrocardiography
was normal. Echocardiography revealed mild pulmonary arterial hypertension. There
were no other comorbidities. CECT of the chest ([Fig. 1A ]) revealed normal caliber (21 mm) main pulmonary artery with an enhancing dilated
(16 mm) serpiginous vascular structure in the right lower lobe connecting the right
interlobar pulmonary artery and the inferior pulmonary vein ([Fig. 1B ]). The inferior pulmonary vein was dilated. To rule out a pulmonary AVM, conventional
pulmonary angiography was performed. The right pulmonary artery demonstrated a normal
course, caliber, and branching pattern ([Fig. 2A ]). There was no early opacification of the pulmonary vein or any abnormal arteriovenous
communication. The venous phase images of the right pulmonary angiography ([Fig. 2B ]) revealed a grossly dilated and tortuous anomalous right pulmonary vein representing
a “pulmonary vein varix.” The patient was treated conservatively for her symptoms
and no intervention was performed for the venous varix. A follow-up echocardiography
a year later revealed normal pulmonary artery pressures.
Fig. 1 Axial contrast-enhanced computed tomography of chest: (A ) Normal caliber of main pulmonary artery (arrow). (B ) Dilated and tortuous course of inferior pulmonary vein (arrow) noted in right lower
lobe.
Fig. 2 Selective right pulmonary angiography. (A ) Late arterial phase shows normal course, caliber, and branching pattern of right
pulmonary artery. (B ) On delayed phase, grossly dilated and tortuous right pulmonary vein (white arrow)
is seen draining into left atrium (open arrow), confirming that this is a pulmonary
vein varix.
Discussion
Pulmonary vein varix is a rare pulmonary vascular anomaly characterized by a focal
abnormal dilatation of the pulmonary vein. The incidence is not known with less than
100 cases published in the literature. There is no gender predilection, and it affects
all age groups. Pulmonary venous varix was first described by Puchet in 1843 during
the autopsy of a child who died from digestive hemorrhage and presented with multiple
multisystemic varices.[1 ] Mouquin et al reported the first angiographic description in a living patient in
1951.[2 ] Because of preferential direction of retrograde flow, the most common location of
a pulmonary vein varix is the right lower lobe followed by the left upper lobe. Pulmonary
varices are classified into three groups according to their appearance: saccular,
tortuous, and confluent.[3 ] These could be congenital or acquired (secondary to mitral valve disease, etc.).
The acquired forms are more common. The etiology of congenital form is unknown. They
are considered to develop as a collateral pathway in the presence of a pulmonary venous
stenosis or atresia.[4 ] They are usually asymptomatic. Rarely, complications such as systemic emboli caused
by the release of thrombi from the varix or, even more infrequently, hemoptysis or
hemothorax caused by rupture of the varix may occur. Onteddu et al described a case
of a pulmonary vein varix near the pulmonary hilum with an associated superior pulmonary
vein stenosis.[4 ]
On imaging, pulmonary varices may mimic AVMs, and case reports of pulmonary varices
misdiagnosed as AVMs on CT scan have been documented.[5 ] The appearance of pulmonary vein varix on CT angiography is in the form of a tortuous
vascular structure of increased caliber of a pulmonary vein that empties into the
left atrium. CT angiography is often limited by flow artifacts and filling of pulmonary
veins can be simultaneous with the arteries that may lead to an incorrect diagnosis
of a pulmonary AVM. A time-resolved magnetic resonance angiography can be used to
assess the pulmonary venous anatomy and exclude a pulmonary AVM. The gold standard
for diagnosis of pulmonary varix is pulmonary angiography. Batram and Strickland reported
specific criteria to diagnose pulmonary venous varix on angiography[2: ] normal pulmonary arteries, no evidence of pulmonary arteriovenous fistula, simultaneous
appearance of varicose veins and normal pulmonary veins, varicose veins draining into
the left atrium, prolonged emptying of varicose veins compared with normal veins,
and dilated and tortuous varicose veins are central, near the hilum, with normal peripheral
veins.
The differential diagnosis of pulmonary varices includes other conditions with dilatation
of the pulmonary veins, such as the hepatopulmonary and scimitar syndromes. Management
of pulmonary vein varix includes observation in asymptomatic individuals and treating
associated comorbidities. Resection is considered if the size of varix increases or
if the patient is symptomatic.
