1. Dr. Natasha Larocque PGY2, Diagnostic Radiology McMaster University
Case of the Month
Dr. Natasha Larocque
PGY2, Diagnostic Radiology
McMaster University

2. Case Presentation
70 year old female presents to the ED with increased SOB, pleuritic chest pain and an elevated D-dimer
Patient has a known history of left upper lobe hemorrhage that was embolized in 2003
No previous imaging available

3. Findings No evidence of pulmonary embolism
There is aplasia of the left main pulmonary artery

4. Findings No evidence of pulmonary embolism
There is aplasia of the left main pulmonary artery

5. Findings No evidence of pulmonary embolism
There is aplasia of the left main pulmonary artery

6. Findings
Aplasia of the left main pulmonary artery results in decreased left lung volume

7. Unilateral Pulmonary Artery Atresia Incidence and Embryology
Prevalence ~ 1/
Male=female
Right > left
Due to a malformation of the 6th aortic arch
Image courtesy of Medicowesome

8. Unilateral Pulmonary Artery Atresia Clinical Presentation
Variable
Asymptomatic
Chest pain/SOB
Recurrent chest infections
Pulmonary hypertension
Hemoptysis
Pleural effusion
High altitude pulmonary edema

9. Unilateral Pulmonary Artery Atresia Associations
Other cardiac anomalies (60%)
ASD, VSD, coarctation, right-sided aortic arch, tetralogy of Fallot, truncus arteriosus
Occur in isolation (40%)

10. Unilateral Pulmonary Artery Atresia X-ray Findings
Absent PA shadow on the affected side
Findings related to volume loss of the affected hemithorax
Cardiomediastinal displacement
Ipsilateral elevated hemidiaphragm
Contralateral compensatory hyperinflation of the hemithorax
CXR for the same patient

11. Unilateral Pulmonary Artery Atresia CT Pulmonary Angiogram
Mainstay for diagnosis
Abrupt termination of a pulmonary artery
Parenchymal findings include
Bronchiectasis
Mosaic attenuation of both lungs due to altered perfusion

12. Unilateral Pulmonary Artery Atresia Complications
Hemoptysis
Bronchiectasis
Pulmonary hypertension
Greatest morbidity

13. Unilateral Pulmonary Artery Atresia Treatment
Surgical
Pneumonectomy and surgical revascularization for recurrent hemoptysis/infections IR
Selective embolization of bronchial/systemic collaterals for patients with massive hemoptysis
Pharmacological
For concomitant pulmonary hypertension

14. References
Steiropoulous, P., Archontogeorgis, K., Tzouvelekis, A., Ntolios, P., Chatzistefanou, A. & Bouros, D. (2013). Unilateral pulmonary artery agenesis: A Case Series. Hippokratia, 17(1):73-76.
Lelegianni, M. & Weerakkody, Y. (2017). Unilateral pulmonary artery atresia. Radiopedia, available from: