Prenatal Detection, Comorbidities, and Management of Vascular Rings

Perioperative and Anesthetic Considerations in Vascular Rings and Slings

Vascular rings represent an increasingly prevalent and diverse set of congenital malformations in which the aortic arch and its primary branches encircle and constrict the esophagus and trachea. Perioperative management varies significantly based on the type of lesion, its associated comorbidities, and the compromise of adjacent structures. Multiple review articles have been published describing the scope of vascular rings and relevant concerns from a surgical perspective. This review seeks to discuss the perioperative implications and recommendations of such pathology from the perspective of an anesthesia provider.

Fetal diagnosis and management of pulmonary artery sling: A case series

OBJECTIVE

Pulmonary artery sling is a rare congenital anomaly accounting for 2% of all patients with vascular anomalies that cause airway obstruction. In the normal heart, the left (LPA) and right (RPA) pulmonary arteries arise in the intrapericardial space. However, in the pulmonary artery sling, the LPA trunk arises in the extrapericardial space from the posterior aspect of the mid RPA and courses posterior to the trachea causing tracheal compression and, at times, bronchial compression. While a full spectrum of congenital cardiac pathology can be identified before birth, only a few case reports document the prenatal diagnosis of an Left pulmonary artery sling (LPAS).

METHOD

We retrospectively identified all cases of prenatal LPAS from three Canadian fetal cardiology centers (2015-2022).

RESULTS

Using the 3-vessel-tracheal view via fetal echocardiography (FE), four fetuses from three pregnancies demonstrated abnormal origin of the LPA from RPA and echogenic trachea. In one of two affected monochorionic twins coronal imaging demonstrated a significant narrowing of the large airways consistent with significant airway obstruction.

CONCLUSION

Prenatal detection of LPAS by FE is possible and should prompt an evaluation for airway obstruction in the coronal view. Investigating associated lesions and genetic testing are recommended for informed shared decision making.

Increased Pulmonary-Aortic Interspace in Fetal Right Aortic Arch: A Matched Case-Control Study

INTRODUCTION

The prenatal detection rate of a right aortic arch (RAA) has increased with the implementation of the three-vessel view (3VV) to the second-trimester anomaly scan formed by the pulmonary artery (PA), aorta (Ao), and superior vena cava (SVC). We examined the value of measuring the distance between PA and Ao in the 3VV in cases with an RAA.

METHODS

We conducted a case-control study in which fetuses with an isolated RAA were matched to 3 healthy controls. Using 3VV images, the distances between PA, Ao, and SVC were measured and the ratio between PA to Ao (PAAo) distance and Ao to SVC (AoSVC) distance was calculated.

RESULTS

Fifty-four RAA cases and 162 matched controls were included. The mean absolute distance PAAo was 3.1 mm in cases and 1.8 mm in controls (p < 0.001), and the mean PAAo/AoSVC ratio was 2.9 and 1.4, respectively (p < 0.001). The ROC curve of PAAo/AoSVC ratio showed a cut-off point of 1.9 with sensitivity and specificity over 87% for the diagnosis of RAA.

CONCLUSIONS

The pulmonary-aortic interspace and the PAAo/AoSVC ratio were significantly larger for RAA cases as compared to controls. If an increased pulmonary-aortic interspace is observed, a PAAo/AoSVC of ≥1.9 can be helpful in the diagnosis of an RAA.

Association Between Airway Stenosis Degree and Respiratory Distress in Infants With a Vascular Ring

Background Although the number of cases of prenatally diagnosed vascular rings is increasing, some cases may remain asymptomatic, and no indicator of the appearance of dyspnea has been established. Thus, we aimed to determine the relationship between the degree of airway compression by the vascular ring on contrast-enhanced computed tomography (CT) and respiratory distress. Methods This is a retrospective study of nine patients diagnosed with vascular rings at a single hospital from July 2010 to December 2019. Data regarding the patient's clinical characteristics, such as prenatal diagnosis, vascular ring type, complicated cardiac disease, and presence or absence of surgery, were recorded. Airway assessment on contrast-enhanced CT was measured in the axial cross-section. Statistical analysis was performed using Statistical Product and Service Solutions (SPSS) (version 25.0; IBM SPSS Statistics for Windows, Armonk, NY). Results Five of the eight patients had respiratory distress. Patients with respiratory distress were less likely to have been diagnosed prenatally (p = 0.04) and had smaller stenosis degree of anteroposterior diameter (p = 0.03). Conclusion Contrast-enhanced CT is useful in patients with vascular rings. Our study suggests that the stenosis degree of the anterior-posterior diameter of the airway is related to dyspnea.

Management of prenatally detected vascular rings: a United Kingdom national survey

OBJECTIVE

To investigate UK variability in prenatal and postnatal management strategy of right aortic arch and double aortic arch (RAA/DAA).

METHODS

Online surveys were sent to senior physicians (consultants) of the National Fetal Cardiology Working Group regarding prenatal diagnosis, counselling, and perinatal management of antenatally diagnosed RAA/DAA and to the British Congenital Cardiovascular Association regarding postnatal management strategies.

RESULTS

There were 28 prenatal and 90 postnatal surveys completed. Prenatally, there was consensus for potential associated chromosomal/genetic anomalies, but there was variation in the risk quoted. Confidence in defining aortic arch morphology was reported by 43% (12/28) of fetal cardiologists. There was variation in what was felt to be possible symptoms/signs of a compressive vascular ring, postnatal investigation, postnatal management, follow-up duration of asymptomatic patients, and indications for surgical intervention.

CONCLUSION

This study has highlighted important areas for future research: improving accuracy of prenatal diagnosis, clarification of potential symptoms, optimal investigation strategies, and indications for surgery.

Pediatric airway compression in aortic arch malformations: a multidisciplinary approach

Background

Aortic arch malformations (AAMs) should be suspected in the presence of persistent respiratory symptoms despite medical treatment or feeding problems at the pediatric age.

Aim

We report a descriptive cohort of patients with AAMs and the local management protocol applied.

Methods

A total of 59 patients with AAM were retrospectively reviewed. Three groups were identified: double aortic arch (DAA), group 1; complete vascular ring (non-DAA), group 2; and anomalous origin of the innominate artery (IA), group 3.

Results

Prenatal diagnosis was available for 62.7% of the patients. In all, 49.2% of children were symptomatic. There was a significantly different prevalence of respiratory symptoms within the three groups: 73.7% in group 1, 24.2% in group 2, and 100% in group 3 (p-value: <0.001). Surgery was considered in the presence of symptoms in patients with DAA and in those with reduction of the tracheal section area greater than 50%. A total of 52.5% of the patients underwent surgical repair (median age 6 months). The median follow-up interval was 21.9 months. Respiratory symptoms improved in most symptomatic patients.

Conclusions

No specific protocols are available for the management of patients with AAMs. Conservative treatment seems to be reasonable for asymptomatic patients or those with airway stenosis less than 50%. A close follow-up is necessary to identify early patients who become symptomatic.

The Impact of Prenatal Diagnosis on Clinical Outcomes of Isolated Vascular Rings From a Statewide Paediatric Cardiology Tertiary Service

BACKGROUND

Vascular rings, including right aortic arch with aberrant left subclavian artery (RAA-ALSCA), double aortic arch (DAA) and pulmonary artery sling (PAS), are congenital anomalies that may cause airway and oesophageal compression. As prenatal detection has improved, literature comparing clinical outcomes of antenatally versus postnatally diagnosed cases continues to emerge. The aim is to define a statewide tertiary paediatric institution's clinical profile and outcomes of prenatal versus postnatally diagnosed isolated vascular rings.

METHOD

A retrospective single-centre review of isolated RAA-ALSCA, DAA and PAS between 1 January 1999 and 31 December 2020 was conducted. Clinical characteristics, surgical and follow-up information were collected. Antenatal and postnatally diagnosed groups were compared.

RESULTS

Out of 123 cases diagnosed with isolated vascular rings, 98 (79.7%) cases had RAA-ALSCA, 21 (17.1%) with DAA, 4 (3.3%) with PAS. The antenatal detection rate was 73.6% in the past decade; 20.3% had a genetic disorder, of which 48% had 22q11.21 microdeletion. Of prenatally diagnosed cases, 31.3% developed symptoms, commonly stridor and dysphagia, at a median age of 2.0 months (IQR 0.0-3.0), compared to a median age of diagnosis for the postnatal cohort of 9 months (IQR 1.0-40.7). Postnatally diagnosed cases were more likely to present with symptoms, primarily respiratory distress, than prenatally diagnosed cases (p=0.006). Fifty-nine (59) cases (50% antenatally diagnosed) required vascular ring division; 6.8% had residual symptoms following surgery.

DISCUSSION

Antenatal diagnosis has improved and leads to better parental awareness and more timely, appropriate intervention. Postnatally diagnosed patients were older, more likely to be symptomatic, underwent more investigations and were commenced on more medications for symptom management prior to diagnosis. One in five cases of isolated vascular ring anomalies carried a genetic diagnosis, which has important implications on prenatal counselling and genetic testing.

Vascular ring: prenatal diagnosis and prognostic management based on sequential cross-sectional scanning by ultrasound

BACKGROUND

In terms of embryonic origin, vascular ring is a congenital anomaly in which the aortic arch and its branches completely or incompletely encircle and compress the trachea or esophagus. Early and accurate diagnosis of a vascular ring is the key to treatment. Prenatal diagnosis mainly relies on fetal echocardiography, but the rate of missed diagnosis and misdiagnosis is still very high, and the prognosis has not been evaluated. The aim of this study was to investigate the accuracy of prenatal diagnosis and to evaluate the prognosis semi-quantitatively according to the shape of the ring and the distance between the vessel and the trachea.

METHODS

From 2019 to 2021, 37,875 fetuses underwent prenatal ultrasound examination in our center. All fetal cardiac examinations were performed using the fetal echocardiography method proposed by the American Institute of Ultrasound in Medicine (AIUM) combined with dynamic sequential cross-sectional observation (SCS). For SCS, the standard abdominal section was taken as the initial section, and the probe was moved cephalically along the long axis of the body until the superior mediastinum had disappeared. If a vascular ring was found, the shape of the ring and the distance of the branch to the airway were observed. The distance relationship with the airway was divided into three grades: I-III; the closer the distance, the lower the grade. The vascular rings were monitored every 4 weeks before birth. All were monitored before surgery or 1 year after birth.

RESULTS

A total of 418 cases of vascular rings were detected. There was no missed diagnoses or misdiagnoses by SCS. The vessels formed different shaped rings according to their origin and route. Grade I, "" and "O" rings have a poor prognosis and are associated with the highest risk of respiratory symptoms.

CONCLUSIONS

SCS can accurately diagnose vascular rings before delivery, evaluate the shape and size of the rings to conduct prenatal monitoring of children until birth, which plays a guiding role in airway compression after birth.

Short-term outcome after the prenatal diagnosis of right aortic arch

OBJECTIVES

To determine the proportion of children that require surgery in the first year of life and thereafter in order to improve the counseling of parents with a fetus with a right aortic arch (RAA).

METHODS

Fetuses diagnosed with isolated RAA, defined as the absence of intra- or extracardiac anomalies, between 2007 and 2021 were extracted from the prospective registry PRECOR.

RESULTS

In total, 110 fetuses were included, 92 with a prenatal diagnosis of RAA and 18 with double aortic arch (DAA). The prevalence of 22q11 deletion syndrome was 5.5%. Six pregnancies were terminated and five cases were false-positive; therefore, the follow-up consisted of 99 neonates. Surgery was performed in 10 infants (10%) in the first year of life. In total, 25 (25%) children had surgery at a mean age of 17 months. Eight of these 25 (32%) had a DAA. Only one child, with a DAA, required surgery in the first week of life due to obstructive stridor.

CONCLUSIONS

Children with a prenatally diagnosed RAA are at a low risk of acute respiratory postnatal problems. Delivery in a hospital with neonatal intensive care and pediatric cardiothoracic facilities seems only indicated in cases with suspected DAA. Expectant parents should be informed that presently 25% of the children need elective surgery and only incidentally due to acute respiratory distress.

Prenatal Diagnosis of Vascular Ring: Evaluation of Fetal Diagnosis and Postnatal Outcomes

BACKGROUND

The impact of fetal echocardiography on the diagnosis and outcomes of vascular ring has not been well examined. We hypothesized that prenatal detection of vascular ring has improved over time and that prenatal diagnosis of vascular ring is associated with earlier intervention and favorable outcomes.

METHODS

This is a single-center, retrospective study of the evolution and outcomes of prenatal diagnosis of vascular ring from 2000 to 2020. We compared clinical presentation, timing of surgical intervention, and outcomes between the prenatally and postnatally diagnosed cases during the same study period.

RESULTS

A total of 170 patients were included: 50 with prenatal and 120 with postnatal diagnosis of vascular ring. Prenatal diagnoses included 42 patients (84%) with right aortic arch (RAA), aberrant left subclavian artery (ALSCA), and a left-sided ductus arteriosus and eight (16%) patients with double aortic arch (DAA). The postnatal cohort consisted mainly of 90 patients (75%) with DAA and 22 (18%) with RAA-ALSCA. None of the postnatally diagnosed cases had undergone a fetal echocardiogram. Numbers (percentage) of prenatally diagnosed cases of vascular ring compared with the postnatal cases improved from 4/31 (13%), to 10/29 (34%), to 14/25 (56%), and to 22/35 (69%), respectively, during 2000-2005, 2005-10, 2010-15, and 2015-20 (P = .032). Vascular ring was an isolated abnormality in 84% and 85% of the prenatal and postnatal cohorts, respectively. Compared with the prenatal cohort, postnatally diagnosed patients with an isolated vascular ring were more frequently symptomatic (66% vs 48%, P < .03) and underwent cross-sectional imaging (69% vs 44%, P = .009) and surgery more frequently (79% vs 48%, P = .003). Surgery was performed at a later patient age (18 [2-147] months vs 4.8 [0.5-42] months, P = .01) and was more often associated with residual symptoms (27/81 [33%] vs 1/20 [5%], P = .01) in the postnatal cohort than in the prenatal cohort.

CONCLUSIONS

The diagnosis of vascular ring by fetal echocardiography has improved over time. A significantly higher incidence of RAA-ALSCA in the prenatal compared with the postnatal cohort suggests that patients with this form of vascular ring often do not present to medical attention with significant symptoms postnatally. Prenatal diagnosis of vascular ring was associated with a lower incidence of symptoms, less frequent use of cross-sectional imaging, earlier age at surgical intervention, and lower likelihood of residual symptoms.

Vascular rings

Vascular rings are congenital aortic arch anomalies that lead to compression of the trachea or esophagus. The goal of this review is to summarize our current recommendations for the management of patients with a diagnosis of a vascular ring. We review the history, classification methods, and epidemiology of the various types of vascular rings. We then propose a management strategy for the relatively new paradigm of fetal diagnosis, including the management of asymptomatic vascular rings. Finally, we finish with a review of the operative techniques and outcomes for the four main categories of vascular rings.

Right aortic arch forming a true vascular ring: a clinical review

OBJECTIVES

This review aims at presenting and summarizing the current state of literature on the presentation and surgical management of a right-sided aortic arch with a left-sided ligamentum forming a complete vascular ring around the oesophagus and trachea.

METHODS

A systematic database search for appropriate literature was conducted on PubMed/MEDLINE. Articles were considered relevant when providing details on the presentation, diagnosis and surgical treatment of this specific congenital arch anomaly in human beings.

RESULTS

Affected patients present with respiratory and/or oesophageal difficulties due to tracheoesophageal compression. Conservative treatment might be reasonable in asymptomatic or mildly symptomatic cases; however, once moderate-to-severe symptoms develop, surgical intervention is definitely indicated. Surgery is commonly performed through a left thoracotomy or median sternotomy and includes the division of the left ductal ligamentum; if a Kommerell's diverticulum is present that is >1.5 times the diameter of the subclavian artery, then concomitant resection of the large diverticulum and translocation of the aberrant left subclavian artery is also conducted. Postoperative morbidity and mortality are low and are rather related to concomitant intracardiac and extracardiac anomalies than to the procedure itself. In a majority of patients, full resolution of symptoms is seen within months to years from the surgery. Nevertheless, there is also a subset of patients who remain with some tracheobronchial narrowing, sometimes even requiring reintervention during follow-up due to persisting or recurring symptoms.

CONCLUSIONS

Overall, the surgical management of a right aortic arch forming a true vascular ring in infancy, childhood and adulthood seems relatively safe and effective in providing symptomatic relief despite some persistent tracheobronchial and/or oesophageal narrowing in some cases.

Morphology of vascular ring arch anomalies influences prognosis and management

OBJECTIVE

This study aimed to explore the anatomical features of aortic arch anomalies associated with vascular rings, hoping to identify those which may increase the risk of symptomatic presentation and surgical intervention.

METHODS

This was a retrospective observational study at a single cardiac unit. Individuals diagnosed with an aortic arch anomaly, either isolated or non-isolated, between June 2014 and September 2018 were included. The morphology of the aortic arch was established via analysis of postnatal echocardiography, CT or MRI scans. CT and magnetic resonance studies were evaluated for the presence of a Kommerell diverticulum in those with aberrant vessels. Case notes were reviewed for relevant clinical data.

RESULTS

Of those with aberrant subclavian arteries, 24/79 (30.4%) were shown to have a Kommerell diverticulum. Additional forms of congenital heart disease were present in 133/227 (58.6%) individuals. Surgical division of the vascular ring was performed in 30/227 (13.2%), most commonly in the setting of a double aortic arch (70.8%). In those with aberrant subclavian arteries, no children without a Kommerell diverticulum were referred for surgery. In those with a Kommerell diverticulum confirmed on imaging, 11/24 underwent surgery.

CONCLUSION

Individuals with a double aortic arch, or an aberrant subclavian artery arising from a Kommerell diverticulum, have the highest requirement for surgical intervention, especially in isolated anomalies. These individuals should remain under monitoring. The subjective nature of symptoms remains problematic. Longitudinal research is required further to understand the natural history of vascular rings and how it links to morphology.

Prenatal diagnosis of complete vascular ring using high-definition flow render mode and spatiotemporal image correlation

Vascular rings (VRs) are defined as congenital abnormalities of the aortic arch and its branches. VR can form a ring that may compress the esophagus and trachea, which likely result in feeding difficulties and respiratory distress. Physicians performing fetal echocardiography are knowledgeable about VRS and can provide this information to pediatric cardiothoracic surgeons. However, VRs are rare and can be missed. The three vessels and trachea (3VT) view used to diagnose VRs has been reported in the literature multiple times but in a small series. We diagnosed three cases of VRs using high-definition (HD) flow render mode and spatiotemporal image correlation (STIC). The composition of the VRs and vessel connections were shown more intuitively. This article reports our experience of the following related cases. In addition, postnatal imaging features of VRs were also evaluated.

Influence of Fetal Diagnosis on Management of Vascular Rings

BACKGROUND

There has been an increasing frequency of fetal diagnosis of vascular rings. We compared management strategies and outcomes of infants with fetal diagnosis to those with postnatal diagnosis to inform recommendations regarding optimal management.

METHODS

Retrospective review was performed of vascular ring operations from 1/2000 to 6/2019. Standard demographic data (preoperative clinical status, timing of diagnosis, cross-sectional imaging, operative and perioperative details, and clinical outcomes) were collected. Statistical analysis was performed to compare characteristics and outcomes of fetal versus postnatal diagnosis.

RESULTS

There were 190 patients, with 15% (n=29) diagnosed prenatally. Anatomic variants were: double aortic arch (n=66, 14 fetal diagnosis), right aortic arch, aberrant left subclavian artery (n=94, 12 fetal diagnosis), circumflex aorta (n=7, 1 fetal diagnosis), and pulmonary artery sling (n=19, 2 fetal diagnoses). Increasing frequency of fetal diagnosis was noted in the past 10 years. In 2012 1/9 (11%) patients had a fetal diagnosis, in 2018 8/11 (72%) had a fetal diagnosis (p<0.001). Patients with a fetal diagnosis were significantly younger at the time of surgery (13.1 months [20.6] vs. 24.0 months [87.0], p=0.029). There was no difference in postoperative complications or length-of-stay (3 days [1] for fetal diagnosis vs. 4 days [3] for postnatal diagnosis, p=0.50).

CONCLUSIONS

Fetal diagnosis leads to the potential for expectant management of vascular ring patients. This has resulted in earlier time of intervention with no increase in postoperative morbidity. This may lead to improved long-term outcomes and potentially alter the natural history for these children.

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.

Outcomes of Surgical Repair of Vascular Rings and Slings in Children: A Word for the Asymptomatic

Vascular rings (VRs) are rare aortic arch anomalies that may present with a wide variety of symptoms related to esophageal and/or airway compression. We reviewed our surgical experience in both symptomatic and asymptomatic children. All children (n = 58) who underwent surgical repair of VRs or slings (mean age 27.4 ± 45.60 months; 36 males [62%]) between March 2000 and April 2020 were included. The most common anatomic variant was a right aortic arch (RAA) with aberrant left subclavian artery (ALSCA) (n = 29; 50%). Kommerell's diverticulum was present in 23 of these patients (79%). The second most common variant was a double aortic arch (n = 22; 38%), followed by pulmonary artery sling (n = 4; 6%), RAA with mirror image branching and left ligamentum arteriosum (n = 3; 5.2%), and left aortic arch (LAA) with aberrant right subclavian artery (n = 1; 1.7%). One patient had a double ring with pulmonary artery sling and RAA with ALSCA. Symptoms were present in 42 patients (72%). Left lateral thoracotomy was the approach in 50 patients (86%), while sternotomy was used in 8 (14%). Symptomatic improvement occurred in the majority of symptomatic patients (93%). There was one perioperative mortality (1.7%) in the symptomatic group which was non-VR related. Morbidities included recurrent laryngeal nerve injury in three patients (5.2%) and transient chylothorax in two (3.4%). Persistence/recurrence of symptoms resulted in one early and one late reoperation. The mean follow-up was 3 ± 5 years. In the current era, VR repair in children including asymptomatic ones can be performed with excellent results. We recommend complete repair of RAA with aberrant LSCA by resection of Kommerell's diverticulum and translocation of the ALSCA to avoid recurrence.

Congenital malformations potentially affecting respiratory function: multidisciplinary approach and follow-up

Background and aim.

Congenital malformations such as oesophageal atresia (OA) and tracheoesophageal fistula (TOF), congenital pulmonary airway malformations (CPAMs), congenital diaphragmatic hernia (CDH) and vascular rings (VRs) can affect lung development and respiratory function. This observational study describes our multidisciplinary approach and respiratory follow-up of children with such congenital malformations.

Methods.

Clinical data of children followed at the Pediatric Respiratory Unit of Parma University Hospital (Italy) between January 2015 and January 2020 were collected.

Results.

Twenty-three patients with congenital malformation affecting lung development were identified. Almost half of our patients were diagnosed with fetal ultrasound. Children attended the clinic at a mean age of 3 (3.7) years and follow-up visits were scheduled every 6 months average. More than half of our patients were hospitalized for lower respiratory tract infections. Six out of 9 children able to perform spirometry showed anomalies in lung function. Chest physiotherapy was recommended especially in children with OA.

Conclusions.

Children with congenital malformations affecting lung development are at risk of short and long-term respiratory complications, especially in the first years of life. OA was the malformation more associated to respiratory problems. Multidisciplinary approach and appropriate personalized follow-up are recommended for the best management of these children. (www.actabiomedica.it)