Isolated Systemic Arterial Supply to Normal Lung with Aneurysm Formation: A Rare Entity with An Even Rarer...

Area of Science:

• Cardiovascular Science
• Thoracic Surgery
• Radiology

Background:

• Isolated systemic arterial supply to normal lung (ISSNL) is a rare congenital lung abnormality.
• Aneurysmal dilatation of the anomalous artery is an infrequent complication of ISSNL, with only 5 prior published cases.
• The condition is thought to arise from persistent primitive aortic branches to the developing lung bud.

Observation:

• A 61-year-old man presented with a retrocardiac mass on screening chest radiograph.
• Axial imaging revealed ISSNL with aneurysmal dilatation of the aberrant artery.
• The aberrant artery shunts high-pressure systemic circulation into the low-pressure pulmonary circulation.

Findings:

• Diagnosis of ISSNL with aneurysmal dilatation can be established non-invasively using contrast-enhanced axial imaging.
• The case contributes to the limited literature on this rare complication.
• Pathogenesis, classification, and management strategies are discussed.

Implications:

• Early diagnosis of ISSNL is crucial, often incidental on screening radiographs.
• Management options include both surgical and endovascular techniques.
• Understanding this rare entity aids in refining classification and treatment of bronchovascular abnormalities.