Recurrent Coarctation After Neonatal Univentricular and Biventricular Norwood-Type Arch Reconstruction

The Society of Thoracic Surgeons Clinical Practice Guidelines on the Management of Neonates and Infants With Coarctation

BACKGROUND

Although coarctation of the aorta without concomitant intracardiac pathology is relatively common, there is lack of guidance regarding aspects of its management in neonates and infants.

METHODS

A panel of experienced congenital cardiac surgeons, cardiologists, and intensivists was created, and key questions related to the management of isolated coarctation in neonates and infants were formed using the PICO (Patients/Population, Intervention, Comparison/Control, Outcome) Framework. A literature search was then performed for each question. Practice guidelines were developed with classification of recommendation and level of evidence using a modified Delphi method.

RESULTS

For neonates and infants with isolated coarctation, surgery is indicated in the absence of obvious surgical contraindications. For patients with risk factors for surgery, medical management before intervention is reasonable. For those stable off prostaglandin E1, the threshold for intervention remains unclear. Thoracotomy is indicated when arch hypoplasia is not present. Sternotomy is preferable when arch hypoplasia is present that cannot be adequately addressed through a thoracotomy. Sternotomy may also be considered in the presence of a bovine aortic arch. Antegrade cerebral perfusion may be reasonable when the repair is performed through a sternotomy. Extended end-to-end, arch advancement, and patch augmentation are all reasonable techniques.

CONCLUSIONS

Surgery remains the standard of care for the management of isolated coarctation in neonates and infants. Depending on degree and location, arch hypoplasia may require a sternotomy approach as opposed to a thoracotomy approach. Significant opportunities remain to better delineate management in these patients.

Associations of Home Monitoring Data to Interventional Catheterization for Infants with Recurrent Coarctation of the Aorta and Hypoplastic Left Heart Syndrome

The post-Norwood interstage period for infants with hypoplastic left heart syndrome is a high-risk time with 10-20% of infants having a complication of recurrent coarctation of the aorta (RCoA). Many interstage programs utilize mobile applications allowing caregivers to submit home physiologic data and videos to the clinical team. This study aimed to investigate if caregiver-entered data resulted in earlier identification of patients requiring interventional catheterization for RCoA. Retrospective home monitoring data were extracted from five high-volume Children's High Acuity Monitoring Program®-affiliated centers (defined as contributing > 20 patients to the registry) between 2014 and 2021 after IRB approval. Demographics and caregiver-recorded data evaluated include weight, heart rate (HR), oxygen saturation (SpO2), video recordings, and 'red flag' concerns prior to interstage readmissions. 27% (44/161) of infants required interventional catheterization for RCoA. In the 7 days prior to readmission, associations with higher odds of RCoA included (mean bootstrap coefficient, [90% CI]) increased number of total recorded videos (1.65, [1.07-2.62]) and days of recorded video (1.62, [1.03-2.59]); increased number of total recorded weights (1.66, [1.09-2.70]) and days of weights (1.56, [1.02-2.44]); increasing mean SpO2 (1.55, [1.02-2.44]); and increased variation and range of HR (1.59, [1.04-2.51]) and (1.71, [1.10-2.80]), respectively. Interstage patients with RCoA had increased caregiver-entered home monitoring data including weight and video recordings, as well as changes in HR and SpO2trends. Identifying these items by home monitoring teams may be beneficial in clinical decision-making for evaluation of RCoA in this high-risk population.

Association of Interstage Monitoring Era and Likelihood of Hemodynamic Compromise at Intervention for Recoarctation Following the Norwood Operation

Background Intensive monitoring has been associated with a lower death rate between the Norwood operation and superior cavopulmonary connection, possibly due to early identification and effective treatment of residual anatomic lesions like recoarctation before lasting harm occurs. Methods and Results Neonates undergoing a Norwood operation and receiving interstage care at a single center between January 1, 2005, and September 18, 2020, were studied. In those with recoarctation, we evaluated association of era ([1] preinterstage monitoring, [2] a transitional phase, [3] current era) and likelihood of hemodynamic compromise (progression to moderate or greater ventricular dysfunction/atrioventricular valve regurgitation, initiation/escalation of vasoactive/respiratory support, cardiac arrest preceding catheterization, or interstage death with recoarctation on autopsy). We also analyzed whether era was associated with technical success of transcatheter recoarctation interventions, major adverse events, and transplant-free survival. A total of 483 subjects were studied, with 22% (n=106) treated for recoarctation during the interstage period. Number of catheterizations per Norwood increased (P=0.005) over the interstage eras, with no significant change in the proportion of subjects with recoarctation (P=0.36). In parallel, there was a lower likelihood of hemodynamic compromise in subjects with recoarctation that was not statistically significant (P=0.06), with a significant difference in the proportion with ventricular dysfunction at intervention (P=0.002). Rates of technical success, procedural major adverse events, and transplant-free survival did not differ (P>0.05). Conclusions Periods with interstage monitoring were associated with increased referral for catheterization but also reduced likelihood of ventricular dysfunction (and a suggestion of lower likelihood of hemodynamic compromise) in subjects with recoarctation. Further study is needed to guide optimal interstage care of this vulnerable population.

Procedural Characteristics and Outcomes of Transcatheter Interventions for Aortic Coarctation: A Report From the IMPACT Registry

Background

Although surgical repair was the traditional first-line treatment for native coarctation of the aorta (CoA), balloon angioplasty (BA) and stenting are now increasingly being performed. We aimed to determine the practice patterns and acute outcomes of transcatheter interventions for native coarctation in the largest multicenter registry for congenital catheterization.

Methods

CoA interventions from the IMPACT (IMproving Pediatric and Adult Congenital Treatment) National Cardiovascular Data Registry were analyzed. The procedure choice and acute outcomes were compared among patients with no prior interventions on the aortic isthmus (native CoA). Procedural success was defined as no major adverse events (MAEs) and a final peak gradient of <20 mm Hg and optimal outcome as no MAEs and a final gradient of <10 mm Hg.

Results

Over the 8-year study period, 5928 CoA procedures were performed, of which 1187 were performed in patients with native CoA. In this group, stenting was performed in more then half of children aged >1 year and >90% of those aged >8 years. Procedural success was achieved in >90% of stenting procedures but in only 69% of BAs. Stent implantation was associated with a higher likelihood of optimal gradient (<10 mm Hg) after adjustment for age and baseline characteristics. MAEs were most common in children aged <1 year (14%), occurred in 2% to 2.5% of those aged 1 to 18 years and in 6.6% of adults (P < .001), and were more likely after BA than after stenting (odds ratio, 0.5; 95% CI, 0.28-0.9; unadjusted P = .02).

Conclusions

Catheter interventions for native coarctation are performed safely in older children and adults, with a high degree of immediate procedural success, particularly with stenting.

Incidence of and Risk Factors for Aortic Arch Interventions After the Comprehensive Stage II Procedure for Hypoplastic Left Heart Syndrome

Minimal data exist about the incidence and risk factors for arch intervention after comprehensive stage II (CSII). Goal of this study was to document incidence of arch interventions after CSII and determine if any differences existed between those who underwent an arch intervention (aiCSII) versus those did not have an intervention. Single-center retrospective chart review of all hypoplastic left heart syndrome patients who underwent a CSII between 6/1/2005 and 2/1/2020 was performed. Univariate analysis was conducted in addition to principal components analysis (PCA). One hundred patients were evaluated. Sixteen patients underwent 24 arch interventions. Age at initial arch reintervention was 1.3 ± 1.2 years (median 1.0 years, range 0.5-2.2 years). Univariate analysis showed that the aiCSII group were more likely to be female, to have had a retrograde arch intervention post-hybrid procedure, and to be younger at time of CSII. On echocardiograms, aiCSII group had significantly higher pre-CSII patent ductus arteriosus velocities, arch velocities on their 1st post-operative and discharge study post-CSII, and arch velocities pre-Fontan. Gradients were higher in the aiCSII via pre-Fontan catheterization. With PCA, echocardiographic and catheterization data remained significantly associated with aiCSII versus those who did not undergo an arch intervention (OR = 4.5 (1.9, 19.8), p = 0.008). Incidence of arch intervention post-CSII was 16%. Echocardiographic arch velocities during the CSII hospitalization were the strongest predictors for subsequent aortic arch interventions. Further studies are needed to determine any modifiable variables that may reduce the incidence of arch interventions.

High-degree Norwood neoaortic tapering is associated with abnormal flow conduction and elevated flow-mediated energy loss

OBJECTIVE

The Norwood neoaortic arch biomechanical properties are abnormal due to reduced vessel wall compliance and abnormal geometry. Others have previously described neoaortic geometric distortion by the degree of diameter reduction (tapering) and associated this with mismatched ventricular-neoaortic coupling, abnormal flow hemodynamic parameters, and worse patient outcome. Our purposes were to investigate the influence of neoaortic tapering (ie, diameter reduction) on flow-mediated viscous energy loss (E_L') in post-Norwood palliated hypoplastic left heart syndrome patients, and correlate flow-geometry with single ventricle power generation.

METHODS

Twenty-six palliated hypoplastic left heart syndrome patients underwent comprehensive cardiac evaluation with 4-dimensional-flow magnetic resonance imaging. Patients were grouped into high- (group H, n = 13) and low- (group L, n = 13) degree neoaortic tapering using the median cutoff value of neoaortic diameter variance. E_L' was calculated along standardized segments using 4-dimensional-flow magnetic resonance imaging. Flow-mediated power loss as a percentage of total power generated by the single ventricle was determined.

RESULTS

Group H had a higher prevalence of abnormal recirculating flow in the neoaorta and elevated neoaortic E_L' in the ascending aorta (1.0 vs 0.6 mW; P = .004). Group H E_L' was increased across the entire thoracic aorta (2.6 vs 1.3 mW; P = .002) and accounted for 0.7% of generated ventricular power versus 0.3% in group L (P = .024). E_L' directly correlated with the degree of ascending aortic dilation (R = 0.49; P = .012).

CONCLUSIONS

Patients with high degree neoaortic tapering have more perturbed flow through the neoaorta and increased E_L'. Flow-mediated energy loss due to abnormal flow represents irreversibly wasted power generated by the single right ventricle. In patients with high-degree neoaortic tapering, E_L' was more than 2-fold greater than low-degree tapering patients. These data suggest that oversizing the Norwood neoaortic reconstruction should be avoided and that patients with distorted neoaortic geometry may warrant increased surveillance for single-ventricle deterioration.

Resource Utilization for Prenatally Diagnosed Single-Ventricle Cardiac Defects: A Philadelphia Fetus-to-Fontan Cohort Study

Background

Healthcare resource utilization is substantial for single‐ventricle cardiac defects (SVCD), with effort commencing at time of fetal diagnosis through staged surgical palliation. We sought to characterize and identify variables that influence resource utilization for SVCD from fetal diagnosis through death, completed staged palliation, or cardiac transplant.

Methods and Results

Patients with a prenatal diagnosis of SVCD at our institution from 2004 to 2011 were screened. Patients delivered with intent to treat who received cardiac care exclusively at our institution were included. Primary end points included the total days hospitalized and the numbers of echocardiograms and cardiac catheterizations. Subanalysis was performed on survivors of completed staged palliation on the basis of Norwood operation, dominant ventricular morphology, and additional risk factors. Of 202 patients born with intent to treat, 136 patients survived to 6 months after completed staged palliation. The median number of days hospitalized per patient‐year was 25.1 days, and the median numbers of echocardiograms and catheterizations per patient‐year were 7.2 and 0.7, respectively. Mortality is associated with increased resource utilization. Survivors had a cumulative length of stay of 57 days and underwent a median of 21 echocardiograms and 2 catheterizations through staged palliation. Right‐ventricle–dominant lesions requiring Norwood operation are associated with increased resource utilization among survivors of staged palliation.

Conclusions

For fetuses with SVCD, those with dominant right‐ventricular morphology requiring Norwood operation demand increased resource utilization regardless of mortality. Our findings provide insight into care for SVCD, facilitate precise prenatal counseling, and provide information about the resources utilized to successfully manage SVCD.

Intervention for arch obstruction after the Norwood procedure: Prevalence, associated factors, and practice variability

OBJECTIVE

Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.

METHODS

From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed.

RESULTS

Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg).

CONCLUSIONS

Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes.