Evaluation of left pulmonary artery sling, associated cardiovascular anomalies, and surgical outcomes using cardiovascular computed tomography angiography

Coexisting Pulmonary Artery Sling and Persistent Left Superior Vena Cava

Congenital vascular anomalies such as pulmonary artery sling and persistent left superior vena cava are rare vascular disorders. We describe a case of a patient who presented with pneumonia and was found to have a pulmonary artery sling as a potential cause of the pneumonia.

Pulmonary artery sling: An overview

Pulmonary artery sling is a rare childhood vascular tracheobronchial compression syndrome that is frequently associated with tracheal stenosis. Consequently, neonates or infants may present with critical airway obstruction if there is long segment airway narrowing and complete rings. Rapid diagnosis of this cardiac vascular malformation and evaluation of the extent and severity of airway involvement is essential to plan surgery, typically a slide tracheoplasty to relieve critical airway obstruction. Long term outcome can be excellent following surgical repair of the stenosed airway and reimplantation of the left pulmonary artery. In this review we focus on the embryology, diagnostic workup, airway investigations and management for this rare but challenging congenital condition.

Computed tomography and magnetic resonance imaging of vascular rings and other things: a pictorial review

Compression of the airway, esophagus or both by aortic and pulmonary vessels can be caused by a variety of anatomical situations. Vascular rings are the most commonly encountered entity; however, compression can also occur from less common anomalies such as a left pulmonary artery sling or innominate artery compression. Vascular rings and other vascular compression abnormalities can be challenging to visualize and image and often require advanced imaging by CT or MRI to better understand the cause and extent of compression. Atretic vascular structures, such as the ligamentum arteriosum or atretic arch, play a key role in creating a vascular ring and do not enhance with contrast agent in a typical fashion. Despite these imaging challenges, classic and useful signs can indicate the presence or absence of a vascular ring or compression.

Partial Anomalous Left Pulmonary Artery Anterior Versus Posterior Types: A Systematic Review

The aim of this study was to investigate the features of partial anomalous left pulmonary artery (PALPA) and differences between cases with posterior versus anterior a nomalous vessels in relation to the tracheobronchial tree. We hypothesized that statistical significance was dependent on the course of the anomalous vessel due to airway compression in the posterior type. This study included cases obtained from the literature (n = 33) and an institution teaching file (n = 2). Information collected: age, sex, medical history, additional anomalies, anomalous vessel course, and respiratory symptoms. Data were analyzed with independent samples t-test and Fisher’s exact test. PALPAs were more commonly anterior than posterior. Mean age: 5.3 years (SD = 12.4) for anterior and 6.8 years (SD = 18.5) for posterior (p = 0.77). Respiratory symptoms: 20% of anterior and 60% of posterior cases (p = 0.032). Tracheobronchial anomalies: 35% of anterior and 60% of posterior cases (p = 0.182). Non-cardiac and non-tracheobronchial anomalies: 30% of anterior and 47% of posterior cases (p = 0.511). Kabuki syndrome: 25% of anterior and 6.7% of posterior cases (p = 0.207). In conclusion, respiratory symptoms were the only significant difference between anterior and posterior PALPA types.

Lung volume determination by dual-source computed tomography in infants with pulmonary artery sling: a case-control study

BACKGROUND

Pulmonary artery sling (PAS) is associated with tracheal stenosis and left pulmonary artery (LPA) dysplasia in infants, both developmental abnormalities that may lead to pulmonary hypoplasia and lung volume changes. As such, we aimed to monitor the effects of tracheal stenosis and pulmonary vascular malformation on lung volumes in infants with PAS and their correlation with lung volumes in infants with PAS using dual-source computed tomography (DSCT).

METHODS

A case-control study was performed. From May 2009 to June 2017, we retrospectively enrolled patients with surgically confirmed PAS and compared them to matched normal controls (A healthy control group comprising age- and gender-matched patients with adequate imaging data was used for the comparisons.). All the patients underwent DSCT examinations. We measured and compared the diameters of the trachea, main bronchus, and main pulmonary artery (MPA) and its branches, and both lung volumes on the axial, and reconstructed CT images.

RESULTS

There were no statistical differences in the diameters of the MPA or right pulmonary artery (RPA) between patients (N=15) and controls (N=28). The diameter of the main bronchus, the bilateral trachea and the left pulmonary artery were all smaller in the PAS group than in the control group, and significant differences were evident in the left lung volume the right lung volume, and the right-to-left lung volume ratio between the 2 groups. Pearson's correlation and linear regression analyses between the diameters of the trachea and MPA, total lung volume, ipsilateral bronchial and pulmonary artery branches, and ipsilateral lung volume ranged from 0.71 to 0.87 and 0.57 to 0.77 for the control and PAS groups, respectively.

CONCLUSIONS

Tracheal stenosis and LPA dysplasia in infants with PAS cause alterations in lung tissue morphology and physiological development, resulting in reduced bilateral lung volumes.

Pulmonary Artery Sling Associated with Stridor from Early Infancy: A Case Report

Background

Pulmonary artery sling is a rare condition in which the left pulmonary artery anomalously originates from a normally positioned right pulmonary artery. The left pulmonary artery arises anterior to the right main bronchus, courses between the trachea and esophagus then enters the left hilum. Respiratory symptoms such as wheezing, stridor, cough, and dysphasia are common in this anomaly.

Case presentation

We describe a 16-month-old male infant presenting recurrent cough, stridor, and wheezing from early infancy. He underwent computed tomography angiography, bronchoscopy, and transthoracic echocardiography, confirming the left pulmonary artery sling diagnosis. Surgical correction of pulmonary artery sling was successfully performed as a new anastomosis between the main pulmonary artery and the left pulmonary artery, as well as tracheoplasty. The infant was discharged without any complications. Follow-up after two years revealed no respiratory symptoms and feeding difficulty.

Conclusion

In the presence of chronic cough, stridor, recurrent wheezing, and other prolonged respiratory symptoms, investigation for possible detection of pulmonary artery sling is recommended.

Left Pulmonary Artery Sling: Postoperative Outcomes for Patients at a Single Center

BACKGROUND

Left pulmonary artery (LPA) sling is a rare anomaly characterized by the origin of the LPA from the right pulmonary artery with a course between the trachea and esophagus. It is often associated with airway and cardiac anomalies.

METHODS

This is a retrospective case series of consecutive patients who underwent LPA sling repair (LPASR) at a tertiary care center over a 35-year period with a focus on tracheal and/or LPA reinterventions and survival.

RESULTS

Between June 1983 and July 2018, 42 patients were identified: isolated LPASR was performed in 16 (38%), LPASR/intracardiac repair in 10 (24%), and LPASR/tracheal repair in 16 (38%). There were 5 (12%) in-hospital and 4 (10%) late deaths. Survival rates (15 years) were as follows: 100% (isolated LPASR), 65% (concomitant intracardiac repair), and 52% (concomitant tracheal surgery). Preoperative intensive care unit (ICU) hospitalization was associated with future intervention on the LPA/trachea (61%, 11/18). The median distribution of blood flow to the left lung post-index surgery was 38%. Freedom from isolated LPA intervention was 100% after isolated LPASR, 93% after LPASR/tracheal surgery, and 69% after LPASR/intracardiac repair. Freedom from isolated tracheal intervention was 92% after isolated LPASR, 73% after LPASR/tracheal surgery, and 78% after LPASR/intracardiac repair.

CONCLUSIONS

ICU hospitalization prior to index surgery may indicate the severity of associated cardiac/tracheal abnormalities as this is associated with increased morbidity and mortality. Patients who underwent LPASR/intracardiac surgery were more likely to undergo isolated LPA intervention and those who underwent LPASR/tracheal surgery were more likely to undergo isolated tracheal intervention.

Relationship between a Tracheal and Left Pulmonary Artery Stenosis Index and the Prognosis of Pulmonary Artery Sling with Tracheal Stenosis

Pulmonary artery sling is a rare congenital pulmonary vascular malformation, often associated with tracheal or bronchial stenosis. Surgical treatment of pulmonary artery sling with tracheal stenosis (T) has a high risk of death and a relatively poor prognosis. This study explored the relationship between the T and left pulmonary artery stenosis (P) ratio and the effects of surgery for pulmonary artery sling with tracheal stenosis. Patients undergoing surgery for pulmonary artery sling in our center from January 2010 to December 2018 were retrospectively analyzed. Routine cardiac-enhanced computed tomography (CT) was performed preoperatively, and the P and T diameters were measured on the CT image. The T/P ratio was then calculated and analyzed. Thirty cases of pulmonary artery sling combined with tracheal stenosis were operated under cardiopulmonary bypass. The mean age at operation was 13.8 ± 13.6 months (1.2-57.1 months, Q1-Q3: 5-17 months), and the mean body weight was 8.8 ± 3.5 kg (3.8-17.3 kg, Q1-Q3: 5.8-11.5 kg). Twenty-three patients survived, and seven died, with an overall survival rate of 76.7%. Twenty-four patients underwent left pulmonary artery re-implantation, six patients underwent simultaneous left pulmonary artery re-implantation and slide tracheoplasty, and patients with intracardiac malformations (ventricular septal defect (n = 6) and atrial septal defect (n = 4)) underwent concurrent repair of the intracardiac defect. All cases had different degrees of tracheal stenosis, and the most narrowed trachea occurred with compression by the left pulmonary artery sling. The T/P ratio in the tracheoplasty group was significantly higher than that in the non-tracheoplasty group. The mortality rate in the T/P ≤ 1.15 group was significantly lower than that in the T/P > 1.15 group. Pulmonary artery sling treatment has a high risk of death. Left pulmonary artery re-implantation is an effective and safe surgical method for treating pulmonary artery sling, and slide tracheoplasty is an effective surgical method to correct tracheal stenosis. Children with T > 78.4% should receive active intervention for the tracheal stenosis, and these children have a considerable postoperative survival rate. The T/P ratio can be used to compare the relative superiority of the two compressions. A T/P ratio > 1.15 can be used as a reference index for intervention in tracheal stenosis and is a risk factor for postoperative death.

A rare association of left pulmonary artery sling with Scimitar syndrome: Recurrent wheezing and respiratory distress in a pediatric patient

Congenital anomalies of the heart and great vessels may lead to localized recurrent pulmonary infections through different mechanisms. Pulmonary artery sling (left pulmonary artery originating from the right pulmonary artery) and Scimitar syndrome are rare causes of wheezing in infants. An 18-month-old female infant with left pulmonary artery sling, Scimitar syndrome, and an anomalous connection of left pulmonary veins to the left atrium was admitted to our clinic. She successfully underwent transcatheter embolization using the Vascular Plug-II on the anomalous systemic arterial supply and repair of pulmonary arterial sling and Scimitar anomaly via a median sternotomy. In conclusion, diagnosis of left pulmonary arterial sling accompanied by abnormalities can be missed in some cases using echocardiography. It may be necessary to conduct more advanced imaging methods before deciding the treatment method to be performed in these patients.

Vascular ring and sling in a fetus who developed esophageal and airway compression after birth

Vascular ring and sling are congenital anomalies of the vascular structure in the thorax with a prevalence of 2.4/10,000 live births. Double aortic arch (DAA), right aortic arch with left ductus arteriosus and aberrant left subclavian artery (RAA-ALSA), and pulmonary artery sling (PAS) are the three common types of vascular ring and sling. These anomalies can be isolated or accompanied by intracardiac malformation. The presence of both vascular ring and PAS is extremely rare. Here, we report a fetus who was prenatally diagnosed with PAS and RAA-ALS, and developed symptoms due to esophageal and airway compression after birth.

Tracheal development after left pulmonary artery reimplantation: an individual study

Pulmonary artery sling (PA sling) often presents as a life-threatening condition requiring urgent surgical correction. We reported 32 cases of PA sling in children who were followed up postoperatively in the past 6 years. All patients with PA slings who were admitted to the hospital from January 2012 to December 2017 and underwent surgery were retrospectively analyzed. The mean age of the 32 patients at repair was 16.97 months (range, 15 days to 128 months). Six patients required ventilator assistance for respiratory failure. All children underwent left pulmonary artery (LPA) reimplantation (n = 32), and 3 patients needed reimplantation slide tracheoplasty (n = 3) due to ventilation weaning failure. Four patients died, 27 patients survived until discharge, and 18 patients were followed up. Pulmonary computed tomography imaging and echocardiography were performed in 18 patients who were followed up. After LPA reimplantation, the tracheal carina area was significantly enlarged compared to that preoperation (p = 0.0002). In this follow-up cohort study, 75% of the patients who underwent LPA reimplantation survived until discharge. The survivors had subsequently well-developed pulmonary arteries and tracheas.

A rare constellation of eventration of right diaphragm, severe right lung hypoplasia, and LPA sling

Left pulmonary artery sling (LPAS) is a rare congenital cardiac anomaly and is commonly associated with complete tracheal rings and various degrees of tracheobronchial compression. We present a very rare association of LPAS and congenital eventration of right hemidiaphragm in this case report.

A Case of Pulmonary Artery Sling Anomaly with Tracheal Stenosis and Management of Difficult Airway

Pulmonary artery sling is a rare congenital vascular abnormality, where the left pulmonary artery originates from the right pulmonary artery, passes between trachea, and esophagus and reaching the left hilum. Cough, wheezing, and difficulty in feeding are three major symptoms. Untreated pulmonary sling carries high morbidity and mortality, most of which is due to the airway and other associated anomalies. Herein, we reported a 40-day-old male infant who admitted to the pediatric intensive care unit with progressive respiratory distress and diagnosed with left pulmonary sling with tracheal stenosis. We discussed the diagnosis and management of pulmonary artery sling and present the successful use of laryngeal mask in difficult airway management.

Early Diagnosis of Left Pulmonary Artery Sling During First Week of Life in a Term Baby Boy: A Case Report

Pulmonary artery sling is a rare cause of neonatal respiratory distress. Most patients with pulmonary artery sling present in early infancy with stridor and signs of respiratory distress. Diagnosis of pulmonary artery sling, like other vascular ring anomalies, can be made using various imaging modalities, and management encompasses urgent surgical repair as a definitive treatment. This is the first paper to report a successfully managed case of an early detected left pulmonary artery sling during the first week of life in a term male patient and to evaluate the diagnostic characteristics in alliance with it. CAse REports (CARE) guidelines were followed for reporting our case. In brief, a case of full-term baby boy was born by normal vaginal delivery and shortly after birth, the baby started to have respiratory distress not improving on O₂. Chest X-ray revealed right upper lobe atelectasis which persisted despite mechanical ventilation and antibiotics. A thoracic CT scan showed developmental malformation of left main pulmonary artery, confirming the diagnosis of "left pulmonary artery sling." The baby was immediately operated. One week later, chest X-ray showed gradual improvement and the baby was discharged home with no postoperative complications. Hence, we suggest that pulmonary artery sling should be suspected in any neonate with respiratory distress and unilateral lung field opacification. The fact that there are only very few reports on this disease raises a need to establish and implement well-defined guidelines and criteria for early diagnosis and management of pulmonary artery sling among newborns.

Double vascular ring: a case report of double aortic arch and concurrent pulmonary artery sling

BACKGROUND

Double aortic arch (DAA) and pulmonary artery sling (PAS) are vascular ring formations that present in neonates and infants with symptoms of respiratory stenosis.

CASE SUMMARY

The patient was a girl with suspected ventricular septal defect (VSD), right aortic arch (AA), left patent ductus arteriosus, and bilateral superior vena cava (SVC) on foetal echography in the first day of life. The girl was delivered at 40 weeks and 4 days of gestation. Ventricular septal defect, DAA, coarctation of the left AA, and bilateral SVC were diagnosed. Contrast-enhanced computed tomography at Day 16 revealed PAS with concurrent anomalous tracheal branching in addition to DAA. The right A2 segmental artery, which supplies the right upper pulmonary artery, showed abnormal branching from the left pulmonary artery (LPA). At 3 months of age, VSD patching, left AA resection distal to the root of the left subclavian artery, arterial ligament dissection, and LPA replacement were performed.

DISCUSSION

Pulmonary artery sling coexists with anomalous branching of the trachea and abnormal branching of the right pulmonary artery (RPA). Our patient had an extremely rare case of DAA concurrent with PAS and presented with anomalous tracheal and RPA branching. We were concerned that increased pulmonary blood flow caused by the VSD would exacerbate tracheal displacement. Radical surgery at 3 months of age resulted in good postoperative progress.

A rare association of left pulmonary artery sling with right pulmonary hypoplasia and total anomalous pulmonary venous connection

We present the second reported case of left pulmonary artery sling with dextrocardia, right pulmonary hypoplasia, and total pulmonary venous connection in a fetus. This case highlights the importance of the determination of pulmonary artery arrangement by fetal echocardiography if right pulmonary hypoplasia and/or congenital heart disease is suspected.

Quantified evaluation of tracheal compression in pediatric complex congenital vascular ring by computed tomography

Clinically, early diagnosis and treatment is important for survival of pediatric with vascular ring (VR) associated with congenital heart disease (CHD), and accurate evaluation of VR is a prerequisite for repair surgical. The study aimed to assess the quantitative characteristics of tracheal compression in pediatrics with VR and CHD using dual-source computed tomography (DSCT), and further provided effective information for surgical decisions. A total of 49 VR patients with CHD and 56 controls were enrolled. The tracheal quantitative measurements (short diameter, long diameter, tracheal area and tracheal length) were obtained, and the degree of tracheal compression was assessed. Our results indicated that VR associated with CHD may cause more serious and complex symptoms, and the greater tracheal compression were found on DSCT when more severe symptoms were present (r = 0.84). The degree of tracheal compression was significantly different within the VR group between those with and without surgery (P = 0.002). Finally, there were good agreement among (1-long diameter ratio), (1-short diameter ratio) and (1-area ratio) in patients and controls, respectively. This study indicated that DSCT enables provides accurate quantitative tracheal compression information for VR pediatrics associated with CHD, and evaluation of the degree of tracheal compression by 1-area ratio may contribute to the repair surgical of VR.

Clinical and imaging features of pulmonary artery sling: The experience in one major medical center

This case series describes echocardiographic and computed tomography angiographic (CTA) characteristics, clinical features, diagnosis, and treatment in 15 patients of Pulmonary artery sling (PAS). Echocardiography is effective in diagnosing PAS, when the main pulmonary artery extends to the right pulmonary artery directly with the left pulmonary artery arising from the right pulmonary artery. CTA, clearly demonstrating the position and extent of trachea compression, the anatomy of PAS and the spatial relationships among the PAS, trachea and the esophagus, is necessary for the final diagnosis. Clinical presentations are caused by the compression of the tracheobronchial tree rather than the PAS itself. Left pulmonary artery reimplantation is the treatment of choice.

Congenital pulmonary vascular anomalies

Congenital pulmonary vascular anomalies are typically found in infancy or early childhood however, some may remain silent and present in adult patients. Anomalies may be separated into anatomic categories based on involvement of the pulmonary arteries, pulmonary veins or both with or without involvement of the lung parenchyma. Association with congenital heart disease and other syndromes is very common. Computed tomography (CT) and magnetic resonance imaging (MRI) are both invaluable at assessment of these anomalies allowing for both diagnosis and detailed treatment planning. This article will focus primarily on the use of CT, as the high resolution evaluation of the lung parenchyma is also important in many of these conditions. In young patients especially, rapid heart rate and concerns of radiation exposure are important considerations when performing CT. This article will discuss scan techniques as well as clinical diagnostic considerations and basic endovascular treatment of congenital pulmonary vascular anomalies.