Influence of Fetal Diagnosis on 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.

Evaluation of tracheal diameter and angles in fetuses with double aortic arch using prenatal ultrasound: implications for postnatal management

Objective

This study aims to analyze the value of prenatal ultrasound in the screening, diagnosis, and treatment of double aortic arch (DAA) malformations.

Methods

A retrospective analysis was conducted on 31 fetal cases with double aortic arch anomalies over a 12-year period from June 1, 2011 to June 1, 2023. The assessment included combined measurements of fetal tracheal internal diameter Z-score and DAA pinch angle, along with ultrasonographic findings, associated anomalies, genetic abnormalities, postnatal CTA images, and long-term postnatal outcomes.

Results

Of the 31 fetal double aortic arch cases, 15 were right aortic arch dominant, 2 were left aortic arch dominant, and 14 had a balanced double arch. Genetic testing was performed on 19 cases, revealing abnormalities in 2 cases, including one Turner syndrome, and one carrier of ichthyosis gene with heterozygous deletion. Out of the total cases, 29 were delivered, and 2 cases were terminated. Prenatal diagnosis accurately identified 29 cases (29/31, 93.5%), which was confirmed by postnatal pathological anatomy, echocardiography, surgery or CTA. Fetal tracheal internal diameter Z-scores were significantly smaller in the symptomatic group than in the asymptomatic group (-1.27 ± 0.49 vs -0.68 ± 0.60, P = 0.018). The area under the curve was 0.776 (95% confidence interval, 0.593-0.960) using a tracheal internal diameter z-score cutoff of -0.73 with a sensitivity of 90% and specificity of 64.7%. The double arch pinch angle was significantly smaller in the symptomatic group than in the asymptomatic group [52.50° (38.25° to 59.00°) vs 60.00° (53.50° to 70.50°), P = 0.035]. The area under the curve was 0.744 (95% confidence interval, 0.554-0.935), and the sensitivity for determining the presence or absence of symptoms was 90% when the cutoff value was 62.5°, with a specificity of 47.1%. Fifteen cases opted for surgery with favorable surgical outcome.

Conclusion

Prenatal echocardiography demonstrates good diagnostic efficacy for fetal double aortic arch. It is also essential to detect the presence of other underlying intra- and extracardiac malformations and genetic abnormalities. There is a significant difference in prenatal tracheal internal diameter Z-scores and double arch pinch angle between asymptomatic and symptomatic DAA infants. Symptomatic infants require early surgery, while asymptomatic infants should be monitored.

Implications of right aortic arch prenatal diagnosis: the multicentric nationwide ARCADE cohort

OBJECTIVES

This study aims to describe the various presentations of the prenatally diagnosed isolated right aortic arch (RAA), that is, without associated congenital heart defect and to evaluate the impact of prenatal diagnosis of isolated RAA in terms of postnatal outcome.

METHOD

In this multicentric retrospective study, from 2010 to 2019, all live births with a prenatal ultrasound diagnosis of isolated RAA were included, with a 1-year postnatal follow-up. The concordance between the different diagnostic steps (prenatal ultrasound, postnatal ultrasound and postnatal CT scan) was evaluated using Gwet's AC1 coefficient.

RESULTS

A total of 309 cases of prenatally diagnosed RAA were analysed, most of which had a left ductus arteriosus (83%). The concordance between prenatal and postnatal ultrasound diagnosis was excellent regarding the RAA type (AC1=0.97, 95% CI=(0.94 to 0.99)). The rare discrepancies mainly involved non-diagnosed or misdiagnosed double aortic arch (2%). CT scan was performed in 108 neonates (35%) and the concordance between prenatal ultrasound and postnatal CT scan was good regarding the RAA diagnosis (AC1=0.80, 95% CI=(0.69 to 0.90)) but poor regarding the distribution of brachiocephalic vessels (AC1=0.21, 95% CI=(0.06 to 0.36)). An associated genetic anomaly was sought for in half of the cases and identified in 4% of the cohort. During the first year of life, 50 (18%) infants presented with vascular ring symptoms and 24 (8%) underwent aortic arch surgery.

CONCLUSION

This multicentric nationwide cohort of 309 prenatally diagnosed isolated RAA demonstrated the reliability of prenatal screening, highlighted the rare cases of discrepancies between prenatal and postnatal diagnosis and underlined the value of CT scan to improve the postnatal follow-up.

TRIAL REGISTRATION NUMBER

NCT04029064.

Double aortic arch: a comparison of fetal cardiovascular magnetic resonance, postnatal computed tomography and surgical findings

BACKGROUND

In double aortic arch (DAA), one of the arches can demonstrate atretic portions postnatally, leading to diagnostic uncertainty due to overlap with isolated right aortic arch (RAA) variants. The main objective of this study is to demonstrate the morphological evolution of different DAA phenotypes from prenatal to postnatal life using three-dimensional (3D) fetal cardiac magnetic resonance (CMR) imaging and postnatal computed tomography (CT)/CMR imaging.

METHODS

Three-dimensional fetal CMR was undertaken in fetuses with suspected DAA over a 6-year period (January 2016-January 2022). All cases with surgical confirmation of DAA were retrospectively studied and morphology on fetal CMR was compared to postnatal CT/CMR and surgical findings.

RESULTS

Thirty-four fetuses with surgically confirmed DAA underwent fetal CMR. The RAA was dominant in 32/34 (94%). Postnatal CT/CMR was undertaken at a median age of 3.3 months (interquartile range 2.0-3.9) demonstrating DAA with patency of both arches in 10/34 (29%), with 7 showing signs of coarctation of the left aortic arch (LAA). The LAA isthmus was not present on CT/CMR in 22/34 (65%), and the transverse arch between left carotid and left subclavian artery was not present in 2 cases.

CONCLUSION

Fetal CMR provides novel insights into perinatal evolution of DAA. The smaller LAA can develop coarctation or atresia related to postnatal constriction of the arterial duct, making diagnosis of DAA challenging with contrast-enhanced CT/CMR. This highlights the potentially important role for prenatal 3D vascular imaging and might improve the interpretation of postnatal imaging.

Narrowing Down the Symptomatology of Isolated Vascular Rings in Children

Vascular rings may cause respiratory or gastrointestinal symptoms due to compression of the trachea and/or esophagus. Advances in imaging have enabled early detection in asymptomatic patients posing new management dilemmas. Surgery is expected to relieve symptoms, although this has not been well studied. We sought to evaluate the presence and pattern of symptoms associated with vascular rings before surgical intervention and to detail symptom resolution after surgery. A 10-year retrospective review of patients diagnosed with an isolated vascular ring was performed between January 2010 and December 2019. 100 patients were identified; 35 double aortic arch (DAA) and 65 right aortic arch and left ligamentum arteriosum (RALL). 73 patients were symptomatic on presentation; 47 had respiratory, 5 had gastrointestinal, and 21 had both types of symptoms. Surgical repair was performed in 75 patients; 74 were symptomatic. Respiratory symptoms were more likely in patients with preoperative tracheal narrowing (p < 0.001). Moderate-severe respiratory symptoms led to surgery in RALL patients (OR 10.6, p = 0.0001). DAA patients were more likely to undergo surgery (p < 0.001) irrespective of symptom severity. At a median post-surgical follow-up of 4 months, there was a significant reduction in symptom burden (p < 0.001), except for asthma symptoms (p = 0.131). Symptom resolution was not dependent on the vascular ring anatomy (p = 0.331) or the age at operation (p = 0.158). Vascular rings are typically accompanied by respiratory symptoms and less commonly GI symptoms, both of which resolve in most patients after surgery. Those who present predominantly with asthma-like symptoms may not achieve resolution after surgery.

Outcomes of Surgical Repair of Aberrant Subclavian Arteries in Adults

BACKGROUND

Symptoms, imaging characteristics, and early and midterm surgical outcomes for aberrant subclavian arteries (ASCA) are not well defined in the adult population.

METHODS

A single-institution retrospective review was conducted of adults undergoing surgical repair of ASCA and descending aorta origin/Kommerell diverticulum (KD) from January 1, 2002, to December 31, 2021. Symptom improvement and differences in imaging characteristics between anatomic groups and the number of symptoms were assessed.

RESULTS

Mean age was 46 ± 17 years. There were 23 of 37 left aortic arches with right ASCA (62%) and 14 of 37 right aortic arches with left ASCA (38%). Of these, 31 of 37 (84%) were symptomatic, and 19 of 37 (51%) had KD size/growth meeting criteria for surgical repair. KD aortic origin diameter was larger in more symptomatic patients: 20.60 mm (interquartile range [IQR], 16.42-30.68 mm) in patients with ≥3 symptoms vs 22.05 mm (IQR, 17.52-24.21 mm) for 2 symptoms vs 13.72 mm (IQR, 12.70-15.95 mm) for 1 symptom (P = .018). Aortic replacement was required in 22 of 37 (59%). There were no early deaths. Complications occurred in 11 of 37 (30%): vocal cord dysfunction (4 of 37 [11%]), chylothorax (3 of 37 [8%]), Horner syndrome (2 of 37 [5%]), spinal deficit (2 of 37 [5%]), stroke (1 of 37 [3%]), and temporary dialysis requirement (1 of 37 [3%]). Over a median follow-up of 2.3 years (IQR, 0.8-3.9 years), there was 1 endovascular reintervention and no reoperations. Dysphagia and shortness of breath resolved in 92% and 89%, respectively, whereas gastroesophageal reflux persisted in 47%.

CONCLUSIONS

The KD aortic origin diameter correlates with the number of symptoms, and surgical repair of ASCA and descending aorta origin/KD effectively relieves symptoms, with low rates of reintervention. Given the operative complexity, surgical repair should be performed in patients meeting size criteria or with significant dysphagia or shortness of breath symptoms.

Post-operative Outcomes for Vascular Rings: A Systematic Review and Meta-analysis

OBJECTIVES

Vascular rings may cause tracheal and/or oesophageal compression. For many patients, symptoms/signs have been present for a long period before diagnosis. However, in the era of prenatal diagnosis, some units advocate universal early surgery. The risks and efficacy of surgery must be known to adequately counsel for the operation. This meta-analysis sought to define the morbidity and mortality associated with surgical correction, and persistent post-operative symptoms.

METHODS

PubMed, Cochrane Library and CINAHL databases were searched for studies that described the outcome of patients undergoing surgery for a double or right aortic arch (DAA or RAA). Non-comparative and random effects model-based meta-analyses were conducted to calculate the pooled rates of mortality, surgical complications, reintervention, and persistent follow-up symptoms.

RESULTS

Nineteen eligible studies were included comprising 18 studies describing outcomes for DAA surgery and 15 for RAA surgery. For DAA surgery, overall mortality rate was 0% [95% confidence interval (CI) 0.0-1.0], post-surgical complication rate 18% [95% CI: 12.0-23.0], prevalence of reintervention 3% [95% CI: 1.0-5.0] and prevalence of symptoms at last follow-up was 33% [95% CI: 17.0-52.0]. For RAA surgery, overall pooled mortality was 0% [95% CI: 0.0-0.0], prevalence of post-surgical complications was 15% [95% CI: 8.0-23.0], reintervention rate was 2% [95% CI: 0.0-4.0], prevalence of symptoms at last follow-up was 40% [95% CI: 26.0-55.0].

CONCLUSIONS

While surgery to correct a vascular ring is safe, the rate of persistent symptoms is high and further strategies must be sought to reduce this burden.

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.

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.

Evaluation of the trachea in fetuses with double aortic arch using prenatal ultrasound: a retrospective cohort study

BACKGROUND

Double aortic arch is the most common form of complete vascular ring. The trachea and/or esophagus could be compressed by the complete vascular ring, which may lead to early respiratory and/or esophageal symptoms in children with double aortic arch. Accurate prenatal assessment of tracheal compression could provide relevant information for perinatal clinical management of double aortic arch and emergency treatment of infants with double aortic arch. The fetal trachea is filled with amniotic fluid and can be clearly visualized with prenatal ultrasound. Previous studies reported the use of prenatal ultrasound to measure the tracheal internal diameters in normal fetuses and showed a linear correlation between the fetal tracheal internal diameters and gestational age. However, to the best of our knowledge, few studies have quantitatively evaluated tracheal compression in fetuses with double aortic arch using ultrasound.

OBJECTIVE

This study aimed to evaluate the tracheal compression caused by the vascular ring in fetuses with double aortic arch using prenatal ultrasound and to analyze the relationship between tracheal compression and postnatal clinical symptoms.

STUDY DESIGN

The data of fetuses with double aortic arch diagnosed with prenatal ultrasound at 2 institutions from January 2011 to April 2021 were retrospectively analyzed. Singleton pregnancies with normal fetuses as the control group were prospectively recruited. The tracheal compression-evaluated by comparing the tracheal internal diameter z scores against the gestational age-was assessed in fetuses with double aortic arch and in normal fetuses. The live-born infants with double aortic arch were divided into symptomatic and asymptomatic groups for the comparison of z scores. The receiver operating characteristic curve for the tracheal internal diameter z score cutoffs and prediction of symptomatic infants with double aortic arch was plotted. Intraobserver and interobserver agreements were investigated.

RESULTS

A total of 26 fetuses with double aortic arch were diagnosed, and 14 fetuses (53.8%) with double aortic arch were delivered alive. Among the 14 live-born infants, 7 (50.0%) were symptomatic, whereas 7 (50.0%) were asymptomatic. The tracheal internal diameter z scores were significantly lower in the double aortic arch group than in the normal groups (-0.62±1.36 vs 0.00±0.78; P<.001). The tracheal internal diameter z scores were significantly lower in the symptomatic group than in the asymptomatic group (-1.42±0.92 vs -0.49±0.96; P=.018). The area under the curve was 0.878 (95% confidence interval, 0.689-1.000). Using a tracheal internal diameter z scores cutoff of -1.21, the sensitivity was 71%, and the specificity was close to 100%. The intraclass correlation coefficients of interobserver and intraobserver agreements were 0.987 (95% confidence interval, 0.980-0.992) and 0.975 (95% confidence interval, 0.955-0.987), respectively.

CONCLUSION

The clinical symptoms in infants with double aortic arch were associated with prenatal tracheal compression, which can be prenatally evaluated using ultrasound. If fetuses are diagnosed with double aortic arch, prenatal surveillance of the tracheal internal diameters and comparison with z score reference ranges could provide pertinent information that would aid perinatal clinical management.

Isolated Vascular Rings Are Common Cardiovascular Malformations

OBJECTIVE

We investigated the prevalence of isolated vascular rings in the general population of Southern Nevada.

METHODS

We identified those prenatally and postnatally diagnosed with an isolated vascular ring between January 2014 and December 2021. We included only those with vascular or ligamentous structures completely encircling the trachea and esophagus. To investigate the prevalence of isolated vascular rings, we included only those with situs solitus, levocardia, and no significant intracardiac malformations.

RESULTS

We identified 112 patients. Of the 112, 66 (59%) were female. There were approximately 211,000 total live births in Southern Nevada for the study period, for an overall prevalence of 5.3 isolated vascular rings per 10 000 live births. However, for the years 2014 to 2017, the average prevalence figure was 3.5 per 10 000 live births, and for the years 2018 to 2021, the average prevalence figure was 7.1 (range 6.5-8.0) per 10 000 live births. Simultaneously, the prenatal detection rate rose from 66% to 86%.

CONCLUSIONS

Isolated vascular rings are common cardiovascular malformations. As prenatal detection rates in the Southern Nevada general population approach 90%, the prevalence figures for isolated vascular rings appear to asymptote at about 7 per 10 000 live births.

Contemporary surgical outcome and symptomatic relief following vascular ring surgery in children: effect of prenatal diagnosis

OBJECTIVES

Our goal was to describe postoperative complications and outcomes in a large contemporary cohort of children with an isolated double aortic arch (DAA) or a right aortic arch (RAA) with left arterial ligament and to assess the impact of foetal diagnosis on outcomes.

METHODS

We performed a retrospective analysis of all patients who underwent surgery for DAA or RAA with left arterial ligament between 2005 and 2019.

RESULTS

A total of 132 children were operated on for a DAA (n = 77) or a RAA (n = 55). Prenatal diagnosis was made in 100/132 (75.8%). Median age at surgery for DAA was 5.0 (1.7-13.3) months and for RAA was 13.9 (6.4-20.1) months. There was no difference in the age at surgery between the prenatal and postnatal cases (8.6 [4.0-15.6] vs 5.4 months [1.8-17.7]; P = 0.37). No surgical deaths occurred. Vocal cord palsy was the most common complication, occurring in 12/132 (9%): of these, 11 resolved spontaneously and 1 required a temporary tracheostomy. Logistic regression demonstrated that older age at operation was the only predictor for a postoperative complication (P = 0.02). Overall, 21/67 (31%) of prenatally detected, symptomatic cases reported residual symptoms/signs 1 year after surgery compared to 18/28 (64%) of postnatally detected cases. Postnatal diagnosis was associated with persistent postoperative symptoms/signs [P = 0.006, odds ratio = 3.9 (95% confidence interval 1.5-9.4)].

CONCLUSIONS

Surgery to relieve a vascular ring resolves trache-oesophageal compressive symptoms in most cases, but parents/patients should be aware that symptoms/signs may persist in the first postoperative year despite effective release of the vascular ring. Earlier surgery and prenatal diagnosis may improve outcomes.

Fetal echocardiographic markers to differentiate between a right and double aortic arch

OBJECTIVES

To describe the fetal echocardiographic features of a double aortic arch (DAA) and secondly, to assess the performance of these features to differentiate between a right aortic arch with left duct (RAA-LD) in a blinded cohort of vascular rings.

METHODS

Review of records to identify surgically confirmed cases of DAA diagnosed prenatally from 2014 to 2018 (cohort-A). Prenatal echocardiograms were reviewed and the segments of the aortic arches anterior and posterior to the trachea, aortic isthmuses and the presence/absence of the Z-sign were described. The utility of these markers were assessed in a separate cohort (B) of fetuses with surgically confirmed cases of DAA or RAA-LD.

RESULTS

Cohort-A comprised 34 cases with DAA; there was a dominant RAA in 32/34 (94%) and balanced left aortic arch (LAA) and RAA in two cases. The proximal LAA was seen in 29/34 (85%), distal LAA in 15/34 (44%) and the LAA aortic isthmus in 4/34 (12%). The "Z" configuration was present in 29/34 (85%) cases. The most predictive marker for DAA in cohort-B was the Z-sign (sensitivity: 100%, specificity: 81%).

CONCLUSION

The "Z" sign is a useful differentiator between RAA-LD and DAA. The absence of visualization of the left aortic isthmus does not preclude the presence of a DAA.

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.