Figure 1
Chest X-ray
Chest radiograph reveals overinflation of the left lung, herniation of the left upper lobe across the midline and compression of the right lung
Tetralogy of fallot with absent pulmonary valve syndrome
SectionPaediatric radiology
Case TypeClinical Cases
Authors
Rosario Matos M, Calder A.
Great Ormond Street Hospital For Children, London, UK
Connected authors
4 days, male
Clinical History
A neonate with known tetralogy of Fallot (TOF) presented with pulmonary insufficiency and cyanosis. The child was under mechanical ventilation.
Imaging Findings
The chest radioraph (Fig.1) performed at day 3 of life revealed overinflation of the left lung, herniation of the left upper lobe across the midline and compression of the right lung.
The child was then examined with prospective gated contrast enhanced cardiac CT. This demonstrated a perimembranous VSD (Fig.2), right ventricular hypertrophy and a small, thickened pulmonary artery annulus, in keeping with known tetralogy of Fallot.
The main pulmonary artery (diameter of approximately 1.9cm) and proximal branch pulmonary arteries to the hila were massively dilated with rapid tapering of the lobar arteries (Figs. 3 and 4).
The left and right main bronchi appeared completely collapsed as they passed behind the dilated pulmonary arteries (Figs. 5 and 6).
There was marked overinflation of the left lung and partial collapse of the right lower lobe and right upper lobe with some relative overinflation of the right middle lobe (Fig.7).
The child was then examined with prospective gated contrast enhanced cardiac CT. This demonstrated a perimembranous VSD (Fig.2), right ventricular hypertrophy and a small, thickened pulmonary artery annulus, in keeping with known tetralogy of Fallot.
The main pulmonary artery (diameter of approximately 1.9cm) and proximal branch pulmonary arteries to the hila were massively dilated with rapid tapering of the lobar arteries (Figs. 3 and 4).
The left and right main bronchi appeared completely collapsed as they passed behind the dilated pulmonary arteries (Figs. 5 and 6).
There was marked overinflation of the left lung and partial collapse of the right lower lobe and right upper lobe with some relative overinflation of the right middle lobe (Fig.7).
Discussion
TOF with absent pulmonary valve syndrome (APVS) is a rare variant of TOF, comprising 3-6% of infants with this congenital cardiopathy. TOF-APVS is characterised by typical TOF features (ventricular septal defect, aortic over-ride, variable degrees of pulmonary stenosis and right ventricular hypertrophy). There is aneurysmal dilatation of the pulmonary arteries, which compresses the central airways leading to the development of tracheomalacia and bronchomalacia [1, 2].
40 to 50% of children present with respiratory symptoms that range from stridor to severe respiratory compromise requiring mechanical ventilation [1].
The chest radiograph may show pulmonary overinflation related to air-trapping, cardiomegaly due to ventricular outflow tract dilatation and grossly dilated aneurismal proximal pulmonary arteries [1, 3].
Ecocardiography is the gold standard examination for the anatomical evaluation of TOF patients in general, though it lacks the assessment of airways [1].
MRI permits the evaluation of congenital heart disease (CHD) without using ionising radiation or exogenous contrast media. It allows cardiac and respiratory gating that reduce artefacts caused by respiration and cardiac pulsation. Furthermore, MRI can provide a wealth of functional data [4, 5]. MRI is usually the modality of choice for cross-sectional evaluation of CHD. However, MRI is poor at depicting the airways and lung parenchyma and MSCT offers an alternative imaging modality in evaluation of congenital heart disease associated with air compromise, such as double aortic arch, left pulmonary artery sling and TOF-APVS.
MSCT, which can also be gated, allows good image quality and minimised artefacts caused by respiration and cardiac pulsation. MSCT obtains isotropic volume data and allows production of high-quality two-and three-dimensional multiplanar reformatted images. Volume rendered images accurately delineate the features inherent to TOF-APVS and evaluate the degree and location of airway compromise [2, 6, 7].
Surgical treatment of TOF-APVS consists of 1) removal of the main pulmonary artery and posterior reconstruction with homograft placement/direct placement of a valved bifurcated pulmonary homograft or 2) performing a LeCompte manoeuvre, which is the transposition of the pulmonary artery anteriorly to the aorta [1]. In this case, a Lecompte manoevre and reduction arterioplasty were done five days after this CT. The child made slow but steady progress post-operatively, and was eventually discharged home 6 weeks following his operation.
Although the outcome for children born with CHD has improved dramatically over the past decade, infants with TOF-APVS presenting with respiratory symptoms early in life suffer significant morbidity and mortality due to airway disease [1].
40 to 50% of children present with respiratory symptoms that range from stridor to severe respiratory compromise requiring mechanical ventilation [1].
The chest radiograph may show pulmonary overinflation related to air-trapping, cardiomegaly due to ventricular outflow tract dilatation and grossly dilated aneurismal proximal pulmonary arteries [1, 3].
Ecocardiography is the gold standard examination for the anatomical evaluation of TOF patients in general, though it lacks the assessment of airways [1].
MRI permits the evaluation of congenital heart disease (CHD) without using ionising radiation or exogenous contrast media. It allows cardiac and respiratory gating that reduce artefacts caused by respiration and cardiac pulsation. Furthermore, MRI can provide a wealth of functional data [4, 5]. MRI is usually the modality of choice for cross-sectional evaluation of CHD. However, MRI is poor at depicting the airways and lung parenchyma and MSCT offers an alternative imaging modality in evaluation of congenital heart disease associated with air compromise, such as double aortic arch, left pulmonary artery sling and TOF-APVS.
MSCT, which can also be gated, allows good image quality and minimised artefacts caused by respiration and cardiac pulsation. MSCT obtains isotropic volume data and allows production of high-quality two-and three-dimensional multiplanar reformatted images. Volume rendered images accurately delineate the features inherent to TOF-APVS and evaluate the degree and location of airway compromise [2, 6, 7].
Surgical treatment of TOF-APVS consists of 1) removal of the main pulmonary artery and posterior reconstruction with homograft placement/direct placement of a valved bifurcated pulmonary homograft or 2) performing a LeCompte manoeuvre, which is the transposition of the pulmonary artery anteriorly to the aorta [1]. In this case, a Lecompte manoevre and reduction arterioplasty were done five days after this CT. The child made slow but steady progress post-operatively, and was eventually discharged home 6 weeks following his operation.
Although the outcome for children born with CHD has improved dramatically over the past decade, infants with TOF-APVS presenting with respiratory symptoms early in life suffer significant morbidity and mortality due to airway disease [1].
Differential Diagnosis List
Tetralogy of Fallot with absent pulmonary valve syndrome
Rudhe syndrome
Pulmonary artery sling
Congenital pulmonary valve insufficiency
Final Diagnosis
Tetralogy of Fallot with absent pulmonary valve syndrome
References
[1] Kirshbom PM, Kogon BE (2004) Tetralogy of Fallot with Absent Pulmonary Valve Syndrome. Semin Thorac Cardiovas Surg Pediatr Card Surg Annu 7:65-71 (PMID: 15283354)
[2] Chen P, Ladino-Torres M (2010) Newborn with tetralogy of Fallot and absent pulmonary valve. Pediatr Radiol 40:87 (PMID: 21042795)
[3] Owens CM, Rees P, Elliot M, Shaw D (1994) Chest Radiographic Changes of the Absent Pulmonary Valve Syndrome. Br J Radiol 67:248-51 (PMID: 8130996)
[4] Frank H, Salzer U, Popow C, Stiglbauer R, Wolleneck G, Imhof H (1996) Magnetic Resonance Imaging for Absent Pulmonary Valve Syndrome. Pediatr Cardiol 17:35-39 (PMID: 8778699)
[5] Taragin BH, Berdon WE, Printz B (2006) MRI assessment of bronchial compression in absent pulmonary valve syndrome and review of the syndrome. Pediatr Radiol 36:71-5 (PMID: 16283289)
[6] Goo HW, Park IS, Ko JK, Kim YH, Seo DM, Yun TJ, Park JJ, Yoon CH (2003) CT of Congenital Heart Disease: Normal Anatomy and Typical Pathologic Conditions. RadioGraphics 23:147-165 (PMID: 14557509)
[7] Choo KS, Lee HD, Ban JE, Sung SC, Chang YH, Kim CW, Lee TH, Kim S, Kim KI (2006) Evaluation of obstructive airway lesions in complex congenital heart disease using composite volume-rendered images. Pediatr Radiol 36:219–223 (PMID: 16391927)
Case information
| URL: | https://www.eurorad.org/case/9207 |
| DOI: | 10.1594/EURORAD/CASE.9207 |
| ISSN: | 1563-4086 |
Figure 2
CT
Volume rendered CT image shows marked dilatation of the pulmonary trunk and right and left pulmonary arteries.
Figure 3
CT
Axial image of gated contrast enhanced cardiac CT (mediastinal window): The left and right main bronchi appeared collapsed (arrowheads).
Figure 4
CT
Volume rendered CT image with air algorithm confirms collapse of the main bronchi.
Figure 5
CT
Axial image of gated contrast enhanced cardiac CT (lung window) shows marked overinflation of the left lung and partial collapse of the right lower lobe.
Figure 6
CT
Axial image of gated contrast enhanced cardiac CT showing marked dilatation of the pulmonary trunk and right and left pulmonary arteries. There is compression of the trachea.
Figure 7
CT
Axial image of gated contrast enhanced cardiac CT showing mesocardia due to left lung overinflation, perimembranous VSD (arrow) and right ventricular hypertrophy
Chest X-ray
Chest radiograph reveals overinflation of the left lung, herniation of the left upper lobe across the midline and compression of the right lung
CT
Volume rendered CT image shows marked dilatation of the pulmonary trunk and right and left pulmonary arteries.
CT
Axial image of gated contrast enhanced cardiac CT (mediastinal window): The left and right main bronchi appeared collapsed (arrowheads).
CT
Volume rendered CT image with air algorithm confirms collapse of the main bronchi.
CT
Axial image of gated contrast enhanced cardiac CT (lung window) shows marked overinflation of the left lung and partial collapse of the right lower lobe.
CT
Axial image of gated contrast enhanced cardiac CT showing marked dilatation of the pulmonary trunk and right and left pulmonary arteries. There is compression of the trachea.
CT
Axial image of gated contrast enhanced cardiac CT showing mesocardia due to left lung overinflation, perimembranous VSD (arrow) and right ventricular hypertrophy