A lung cyst harbouring a congenital pulmonary varix

Abstract

A non-smoker man in his second decade presented to a medical centre with intermittent haemoptysis over 2 years. The haemoptysis was infrequent initially to be ignored, but later, the episodes increased in amount and frequency. Routine blood tests including coagulation profile showed normal results. The chest radiography and echocardiography were normal. The contrast-enhanced CT scan of the chest showed a cystic lesion with intracystic abnormality and surrounding ground-glass opacity in the left upper lobe. The CT pulmonary angiography and invasive pulmonary angiography showed the abnormality to be a dilated pulmonary vessel draining into the left atrium, thereby confirming the diagnosis of congenital pulmonary varix contained within a lung cyst. The patient underwent a successful lobectomy following which he experienced no further haemoptysis.

Background

A pulmonary varix, also known as a pulmonary vein aneurysm, is an abnormal dilatation of the pulmonary vein. It is a very rare finding. However, the disease has been reported more commonly in the recent era due to advancements in imaging. Pulmonary varix can be congenital or acquired secondary to mitral valve disease. Congenital pulmonary varix is detected commonly as an incidental finding in an asymptomatic patient but rarely haemoptysis, cough or other complications may be seen. It may be confused with lung mass or pulmonary arterio-venous malformation (PAVM) on routine chest imaging. Pulmonary angiography is the gold standard test for confirmatory diagnosis. Here, we report a case of congenital pulmonary varix within a lung cyst presenting with recurrent massive haemoptysis that was successfully managed with lobectomy. To the best of our knowledge, only one case has been reported in literature with similar radiologic presentation. We report this case to highlight the unusual clinical and radiologic presentation of this disease.

Case presentation

An otherwise healthy man in his second decade presented to the pulmonology outpatient department with complaints of intermittent haemoptysis for 2 years. The haemoptysis initially occurred 2–3 times a month with scanty amounts of blood but progressively the episodes increased in frequency (5–6 times a month) and severity (100 to 200 mL) for the last few months. He had no other symptoms like cough, chest pain, shortness of breath, joint pain or bleeding from other sites. He had no addictions or any occupational exposures. There were no other comorbidities. The family histories were insignificant. He was vitally stable, and the systemic examination was normal.

Investigations

Routine blood investigations including the coagulation profile and urine examination were all within normal limits. The chest radiograph (figure 1) and two-dimensional echocardiography were normal. The contrast-enhanced CT of the chest revealed a thin-walled cystic lesion in the posterior segment of the left upper lobe with a nodular density along the cyst wall bulging into the cavity with surrounding ground-glass opacities. The intracystic abnormality was also found to be continuous with an adjacent pulmonary vessel (figure 2). A bronchoscopy was performed with bronchoalveolar lavage from the left upper lobe. The lavage fluid was negative for acid-fast bacilli, gene-Xpert, bacterial and fungal cultures. The lavage fluid malignant cytology was also negative.

Figure 1.

Chest radiograph showing bilateral normal lung parenchyma.

Figure 2.

Contrast enhanced CT scan (wide window settings, maximum intensity projection) showing a thin-walled cystic lesion with a nodular density along its wall (arrow) with surrounding ground-glass opacities in the posterior segment of the left upper lobe in the sagittal (figure 2A) and coronal (figure 2B) sections.

Differential diagnosis

Based on CT scan findings, a differential of PAVM versus pulmonary varix was kept. To identify the exact source of bleeding, CT pulmonary angiography was performed. On CT pulmonary angiography, the intracystic abnormality was found to be an abnormal focally dilated pulmonary vessel draining into the left atrium (figure 3), suggesting its pulmonary venous origin. The invasive pulmonary angiography (IPA) was also performed to confirm the bleeding source. The arterial phase and lung parenchymal phase of the IPA were unremarkable, ruling out the pulmonary arterial source. However, in the venous phase, there was an abnormal dilatation of the pulmonary vessel draining into the left atrium, confirming its venous origin. There was a delayed contrast emptying from the dilated pulmonary vein compared with the normal pulmonary veins (video 1). The diagnosis of congenital pulmonary varix within a cyst was made based on CT pulmonary angiography and IPA findings.

Figure 3.

CT pulmonary angiography coronal section showing the intracystic nodule (arrow) traced to an adjacent pulmonary vessel draining into the left atrium.

Video 1. Invasive pulmonary angiography showing the characteristic features of pulmonary varix.

bcr-2023-259511supp001.mp4 ^{(668.9KB, mp4)}

DOI: 10.1136/bcr-2023-259511.video01

Treatment

Since the patient was symptomatic with recurrent haemoptysis, he was referred for surgery. The patient underwent a left upper lobectomy with an uneventful postoperative period.

Outcome and follow-up

After the surgery, the patient is on follow-up for 1 year without any further episodes of haemoptysis.

Discussion

Pulmonary varix refers to an abnormal localised dilatation of a segment of a pulmonary vein. It is typically diagnosed when the vein’s diameter exceeds 50% of its resting size.¹ It is an extremely rare condition. There is no gender or age predilection.² It can be either congenital or acquired. During embryogenesis, at the transition from splanchnic venous drainage to pulmonary venous drainage, aberrant development is hypothesised to be the cause of congenital pulmonary varix.^{3 4} The acquired cases are caused by reflux and pulmonary venous hypertension secondary to mitral valve disease such as mitral stenosis or regurgitation and rarely hepatic cirrhosis.⁵ Our patient most likely had congenital aetiology as no underlying cardiac abnormality was found.

Most of the patients with pulmonary varix are asymptomatic and detected incidentally. Sometimes symptoms like haemoptysis, cough, and complications such as dysphagia and middle lobe syndrome due to compression of adjacent structures may occur.⁶ Patients may experience the symptoms of mitral insufficiency or mitral stenosis in acquired cases. The congenital pulmonary varix may rarely be associated with other congenital cardiovascular malformations like coarctation of the aorta, patent ductus, pulmonary vein stenosis, ventricular septal defects, etc.⁷ Other presentations in the form of a mediastinal mass,⁸ haemothorax from varix rupture and cerebral infarction due to embolic stroke⁶ have also been reported.

Radiologic imaging plays a vital role in the diagnosis of pulmonary varix. Radiologically, the most common presentations are mass-like lesions⁹ that may or may not be evident in the routine chest radiograph. The contrast-enhanced CT can help in the vascular association of the lesion. The PAVM is the closest differential of pulmonary varix as both have similar clinic-radiologic presentation. The PAVM presents as a mass-like lesion with a feeder pulmonary artery branch and a drainer pulmonary vein branch. However, the pulmonary varix continues with the pulmonary vein branch terminating to the left atrium without direct communication with the pulmonary artery branch.² Since there is capillary shunting in PAVM, a large PAVM can manifest with hypoxaemia in contrast to pulmonary varix. It is important to differentiate the two as their management differs. The PAVM requires treatment even if asymptomatic, whereas asymptomatic pulmonary varix does not require intervention. It is difficult to differentiate the two based on contrast-enhanced CT alone. CT pulmonary angiography allows accurate delineation of arterial and venous anatomy.²

Recently, with the advancement in CT imaging techniques, the diagnosis of pulmonary varix has been possible with non-invasive imaging too. The 3D and 4D CT reconstruction images can visualise the dynamics of pulmonary blood flow in the arterial and venous phases and thus are expected to distinguish pulmonary varix from PAVM.¹⁰ However, these techniques are limited by wide availability.

Pulmonary angiography remains the gold standard for the diagnosis of congenital pulmonary varix. Pulmonary angiography gives accurate information on the dynamics of pulmonary blood flow, thus helping to differentiate from PAVM. The confirmatory diagnosis of pulmonary varix requires the presence of five characteristic features in the pulmonary angiogram as described by Bartram et al: (1) a normal pulmonary arterial tree during the arterial phase; (2) the veins supplying the varix are seen in the venous phase and varix fills at the same pace as the normal pulmonary veins¹¹; (3) the left atrium receives varix’s direct drainage; (4) varix empties the contrast material more slowly compared with other veins; and (5) varicosity affects only the proximal portion of the vein while the peripheral part is normal.^{2 12} Three morphological types of pulmonary varix are known: saccular, tortuous and confluent, which can be distinguished by pulmonary angiography. The saccular type is the most common.^{3 13} Our patient had all five characteristics of pulmonary angiography and was diagnosed with a saccular type of pulmonary varix.

Our patient had an unusual radiologic manifestation of pulmonary varix within a lung cyst. The surrounding ground glassing in our patient was likely due to active haemoptysis. To the best of our knowledge, only one such case has been reported on the varix within cyst by Park et al.¹⁴ Their patient was asymptomatic and was incidentally detected during workup for pneumonia. The association of congenital pulmonary varix within a cyst could be related to a developmental defect. Since most of the patients with congenital pulmonary varix are asymptomatic, they may be underdiagnosed. Thus, similar radiologic presentation of intracystic pulmonary varix may also be underreported.

The treatment of pulmonary varix depends on the underlying cause and degree of symptoms. Acquired pulmonary varix due to mitral valve insufficiency may resolve after correction of the valvular disease.¹⁵ For congenital asymptomatic pulmonary varix, close follow-up and monitoring without intervention are preferred. Earlier reports have shown that such patients remain stable without symptoms for 4–5 years of follow-up.⁴ The symptomatic cases and those with a high risk of complications require treatment. Treatment modalities include transcatheter coil embolisation or surgery in the form of wedge resection or lobectomy. The coil embolisation is difficult because of the difficulty in endovascular access to the left atrium and pulmonary venous system. Most frequently, interatrial transseptal puncture from the right atrium is used with the Brockenbrough technique.¹⁶ Surgery remains the treatment of choice when the aneurysm is progressively increasing¹⁷ or if the patient has recurrent or massive bouts of haemoptysis.¹⁸ Our patient was managed with lobectomy because of recurrent massive haemoptysis. Also, lobectomy proved effective as the patient remained asymptomatic on follow-up visits.

Patient’s perspective.

I was suffering from blood in sputum for quite a long time and it affected my day-to-day activities. I was reluctant at first to seek medical help. But as the problem increased, I got admitted and had to undergo a series of tests. Surgery was advised as an option by my doctor. I had to undergo it despite my fears as I wanted to get better. After my surgery, I am now able to carry out my work without any difficulties and fear of blood when I cough every time.

Learning points.

• Pulmonary varix or pulmonary vein aneurysm is usually asymptomatic but can rarely present with recurrent massive haemoptysis, a mass lesion or an embolic stroke.

• Pulmonary varix needs to be differentiated from pulmonary arteriovenous malformation because their management is different despite a similar clinicoradiologic presentation.

• Pulmonary angiography is the gold standard for the diagnosis of pulmonary varix. 3D and 4D reconstruction of CECT images can help in non-invasive diagnosis.

• The pulmonary angiographic findings of the normal pulmonary arterial tree, varix filling during the venous phase, delayed emptying, drainage into the left atrium and proximal pulmonary vein involvement clinch the diagnosis of pulmonary varix.

• Treatment of asymptomatic pulmonary varix is course observation. Symptomatic patients require correction of underlying cardiac pathology, coil embolisation or surgery based on the aetiology and severity.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).