Congenital internal mammary artery-to-pulmonary artery fistulas: a case report

Transpleural systemic artery-to-pulmonary artery communications in the absence of chronic inflammatory lung disease. A case series and review of the literature

AIM

To describe the causes and computed tomography (CT) and angiographic appearances of transpleural systemic artery-to-pulmonary artery shunts in patients without chronic inflammatory lung disease and determine their best management.

MATERIALS AND METHODS

All patients referred to a tertiary referral unit between January 2009 and January 2020 in whom a diagnosis of a systemic-to-pulmonary artery communication without underlying chronic inflammatory lung disease was subsequently made have been included in this report. Medical records and imaging findings were reviewed retrospectively.

RESULTS

Ten patients (male: female ratio = 7:3; median age 42 years [range 22-70 years]) with systemic artery-to-pulmonary artery shunts without chronic inflammatory lung disease were identified. Five were misdiagnosed as having a pulmonary arteriovenous malformation and had been referred for embolisation. In six patients, there was either a history of accidental or iatrogenic thoracic trauma or of inflammatory disease involving the pleura, and in two patients, in whom a previous medical history could not be obtained, there were CT features suggesting previous pleural inflammatory disease. Two shunts were thought to be congenital. All individuals were asymptomatic other than one with localised thoracic discomfort that dated from the time of surgery. All patients were managed conservatively and have remained well with a median follow-up of 4.5 years (range 1-11.3 years).

CONCLUSIONS

Localised transpleural systemic artery-to-pulmonary artery shunts in the absence of chronic inflammatory lung disease are usually related to previous thoracic trauma/intervention or abdominal or pulmonary sepsis involving a pleural or diaphragmatic surface. Congenital shunts are rare. The present study and much of the literature supports conservative management.

Unusual Pulmonary Arterial Filling Defect caused by Systemic to Pulmonary Shunt in the Setting of Chronic Lung Disease Demonstrated by Dynamic 4D CTA

Even though pulmonary embolism is by far the most common cause of filling defect in the pulmonary arterial system, other less common etiologies should be considered especially in the setting of atypical clinical scenario or unusual imaging findings. Unusual pattern of filling defect in the pulmonary artery in the setting of chronic inflammatory/fibrotic parenchymal lung disease should raise the concern for systemic to pulmonary artery shunt. This diagnosis is typically made by conventional angiography. Dynamic 4D CT angiography however can be a safe, noninvasive and effective alternative tool for making such a diagnosis. It has the added value of multiplanar reconstruction capabilities and providing detailed anatomy which can be vital for interventional radiologists when planning their approach for possible intervention. We present 2 cases of such shunts, and illustrate the demonstration of these shunts by using dynamic 4D CT angiography.

Embolization of multiple systemic artery to pulmonary artery fistula with recurrent hemoptysis

Herein, we report a case of multiple systemic arteries to pulmonary artery fistulas without any underlying causes, presenting recurrent hemoptysis. Transcatheter embolization was successfully performed several times on multiple systemic feeding arteries. Multiple systemic arteries to pulmonary fistulas can be a source of uncontrolled bleeding, and embolization may be a reasonable therapeutic option to control the bleeding.