Recoarctation after the norwood I procedure for hypoplastic left heart syndrome: incidence, risk factors, and treatment options

Morphology of the native ascending aorta after the Norwood procedure for aortic atresia: impact on survival and right ventricular dysfunction

OBJECTIVES

Our goal was to evaluate the impact of variable morphology of the native ascending aorta after the Norwood I procedure in patients with hypoplastic left heart syndrome/aortic atresia on long-term survival and systemic right ventricular dysfunction.

METHODS

Of 151 survivors of the Norwood procedure for hypoplastic left heart syndrome/aortic atresia at our institution between January 2001 and December 2020, we included patients with available and measurable aortograms prior to stage II palliation. The diameter of the native ascending aorta, the length of the native ascending aorta and the angle between the native ascending aorta and the proximal pulmonary artery were measured. We investigated the impact of these morphologic parameters on mortality and on right ventricular dysfunction (defined as at least moderate).

RESULTS

Angiograms were available for 78 patients. The median diameter of the native ascending aorta was 3.2 mm (2.6-3.7), the median length of the native ascending aorta was 15.4 mm (13.3-17.9) and the median angle between the native ascending aorta and the proximal pulmonary artery was 44° (35°-51°). During the median follow-up of 6.5 years, 8 (10%) patients died and systemic right ventricular dysfunction occurred in 19 patients (24%). No significant association between aortic morphology and mortality could be detected. Right ventricular function was negatively affected by a larger angle between the native ascending aorta and the proximal pulmonary artery [odds ratio 1.07 (1.01-1.14), P = 0.02].

CONCLUSIONS

In survivors of the Norwood procedure for hypoplastic left heart syndrome/aortic atresia with available angiograms, no significant association between native aortic morphology and mortality could be demonstrated after stage II palliation, within the scope of this limited study. A larger anastomosis angle between the native ascending aorta and the proximal pulmonary artery emerged as a risk factor for right ventricular dysfunction.

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.

Balloon Dilatation in the Management of Congenital Obstructive Lesions of the Heart: Review of Author's Experiences and Observations-Part I

Balloon dilatation techniques became available to treat congenital obstructive lesions of the heart in the early/mid-1980s. The purpose of this review is to present the author's experiences and observations on the techniques and outcomes of balloon dilatation of pulmonary stenosis (PS), aortic stenosis (AS) and aortic coarctation (AC), both native and postsurgical re-coarctations. Balloon dilatation resulted in a reduction of peak pressure gradient across the obstructive lesion at the time of the procedure as well as at short-term and long-term follow-ups. Complications such as recurrence of stenosis, valvar insufficiency (for PS and AS cases) and aneurysm formation (for AC cases) have been reported, but infrequently. It was recommended that strategies be developed to prevent the reported complications.

Balloon-expandable stents for native coarctation of the aorta in children and adolescents

Although balloon-expandable stent implantation for native aortic coarctation is a preferred method in the adolescent age group, there are insufficient data about indications for and the efficacy of the procedure in a younger age group. The aim of this study was to compare and evaluate the data of young pediatric and adolescent patients who underwent balloon-expandable stent implantation because of native aortic coarctation. The retrospective analysis included the demographic characteristics and data related to the procedure and follow-up of patients who underwent stent implantation for native aortic coarctation between August 2010 and November 2017. Patients with re-coarctation were excluded from the study. The patients were separated into 2 groups as the adolescent group (Group I: 10-18 years) and the pediatric group (Group II: ≤ 9.9 years). Group-I comprised of 18 patients and Group-II, 32 patients. Covered stent was implanted to 32 (73%) patients and uncovered stent to 12 (27%) patients. The procedural success rate was 100%. Following stent implantation, peak systolic gradient decreased significantly in both groups (P < .0001) (Group-I: from 35.9 ± 16.6 mm Hg-2.2 ± 3.4 mm Hg, Group II: from 34 ± 13.3 mm Hg-3 ± 4.09 mm Hg). Complications developed in 3 patients, and all in Group I. Femoral hematoma developed in 1 patient, balloon rupture occurred during the procedure in 1 patient, and there was temporary loss of pulse in 1 patient. All the complications were treated successfully. All the patients were taking anti-hypertensive drugs before intervention and during the mean 23-month follow-up period (range, 2-84 months), hypertension recovered in 35 (80%) patients and drugs were terminated. Stent implantation for aortic coarctation in the pediatric age group may provide pleasing results, reducing the coarctation gradient, providing effective dilatation in the lesion area and eliminating hypertension.

Surgical reintervention on the neo-aorta after the Norwood operation

OBJECTIVES

We sought to identify the prevalence of surgical reintervention on the neo-aorta after Norwood procedure and its impact on long-term outcomes.

METHODS

We reviewed the medical records of all patients who underwent Norwood procedure. The impacts of surgical neoaortic reintervention on outcomes were analysed in each stage of palliation.

RESULTS

A total of 335 patients were included in this study. Thirty patients underwent surgical reintervention on the neo-aorta after Norwood procedure. The timing of initial reintervention was before stage II in 13 patients, at stage II in 7, between stage II and stage III in 5, at stage III in 3 and after stage III in 2. A reintervention before stage II was significantly associated with mortality (HR 14.4, 95% confidence interval 6.00-34.6, P < 0.001). In patients who underwent stage II (n = 251), reintervention had no significant impact on mortality. In patients who underwent stage III (n = 188), the previous reintervention was significantly associated with higher mean pulmonary pressure (P = 0.05) and a higher rate of reduced ventricular function (P = 0.002). Greater than mild atrioventricular valve regurgitation was significantly associated with the development of a neoaortic arch stenosis after stage II (P = 0.03).

CONCLUSIONS

Surgical reinterventions on the neo-aorta were required in each inter-stage phase. A surgical neoaortic reintervention was not related to increased mortality after stage II but significantly associated with a higher rate of reduced ventricular function and elevated mean pulmonary artery pressure.

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.

Aortic arch reconstruction in the Norwood procedure using a curved polytetrafluorethylene patch

OBJECTIVES

The aortic arch enlargement in the Norwood procedure is classically carried out using a curved homograft patch on the inner curvature of the neoaortic arch. The study investigates the outcome of a newly used artificial patch from a vascular prosthesis as an alternative to a homograft patch.

METHODS

Since April 2007, we used curved polytetrafluorethylene (PTFE) patches cut out of a prosthesis as an alternative to homograft patches for the aortic arch reconstruction. The decision for either patch material was made due to anatomic reasons, preferring PTFE patches in larger aortas. In this study, 224 Norwood patients, operated between April 2007 and April 2018, were analysed. A total of 104 patients received a PTFE patch (group PTFE), and 120 patients got a pulmonary homograft patch (group homograft). A single-centre retrospective analysis was carried out concerning postoperative course and long-term follow-up regarding aortic arch interventions and reoperations and comparing the 2 material groups.

RESULTS

There were no material associated operative or postoperative complications. In-hospital mortality was 13% in group PTFE. Six children died late during follow-up (6%). One aortic isthmus dilatation (1%) was carried out 12 months after the Norwood procedure in this group, no arch reoperation was necessary during the complete follow-up.

CONCLUSIONS

The curved PTFE patch showed good qualities in operative technical demands and excellent long-term results. In selected cases of hypoplastic left heart syndrome, it can be well used as alternative to the pulmonary homograft.

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.

Porcine Small Intestinal Submucosa May Be a Suitable Material for Norwood Arch Reconstruction

BACKGROUND

Norwood palliation typically requires patch augmentation of the ascending aorta and aortic arch. Patients having undergone Norwood palliation are at risk of recurrent arch obstruction, the risk of which may be affected by the type of patch material used at the time of Norwood palliation. We sought to determine the freedom from neoaortic arch reintervention and overall survival in patients who underwent Norwood palliation utilizing porcine small intestinal submucosa (PSIS) as the patch material.

METHODS

Retrospective chart review was performed to identify patients who underwent a Norwood operation utilizing PSIS material at our institution. Cardiac diagnosis, age at surgery, shunt type, need for reintervention, and outcome (survival, transplant, and death) were evaluated.

RESULTS

Forty-four patients had PSIS material utilized for arch reconstruction at the time of Norwood palliation. There were only five neoaortic arch reinterventions in 4 patients (11.4%). An additional 10 reinterventions, unrelated to the PSIS patch, were performed, including five shunt revisions and five branch pulmonary artery interventions. There were 3 deaths, and 5 patients underwent transplantation. Median follow-up was 387.5 days (range, 4 to 1,513).

CONCLUSIONS

Freedom from neoaortic arch reintervention and survival after Norwood palliation with PSIS patch material is promising. The PSIS appears noninferior and may be an appropriate tissue choice for Norwood palliation. Studies with longer follow-up are needed to determine the rate of neoaortic reintervention over time.

Coarctation of the aorta-stenting via Glidesheath Slender in a newborn with recoarctation early after a Norwood operation

In this article, we report on a newborn with hypoplastic left heart syndrome in whom recoarctation of the aorta was treated with a bare metal stent (Cook Formula 414 Stent) in the early postoperative period after a Norwood procedure. To reduce the risk for scarring and occluding the femoral artery the stent was implanted via 5F Glidesheath Slender sheath.

Predicting the Need for Neoaortic Arch Intervention in Infants with Hypoplastic Left Heart Syndrome Through the Glenn Procedure

Neoaortic recoarctation is present in up to over one-third of patients having undergone the Norwood procedure for hypoplastic left heart syndrome. Some of these patients will require reintervention by catheterization or surgery through the time of the Glenn procedure. Echocardiography and catheterization are often utilized in this period to assess hemodynamics although no specific criteria have been identified to predict whether and when neoaortic arch reintervention will be needed. We sought to identify predictors, including but not limited to echocardiographic and catheterization gradients, to predict such intervention. A retrospective analysis was conducted including patients with hypoplastic left heart syndrome. Patients with significantly comorbid lesions such as isomerism, anomalous pulmonary venous connections, and significant atrioventricular valve insufficiency were excluded as were patients without interstage echocardiographic and catheterization data. Receiver operator curve analysis was performed to establish peak-value gradients by echocardiography and catheterization that were predictive of neoaortic reintervention from the time of the Norwood through the time of the Glenn. These values were then entered into a multivariate regression with several other factors to determine what factors were predictive of need for such intervention. Bland-Altman analysis was conducted to compare echocardiographic and catheterization gradients. A peak echocardiographic gradient of 26 mmHg (100 % sensitivity, 85 % specificity) and a peak-to-peak catheterization gradient of 8.5 mm Hg (83 % sensitivity, 86 % specificity) were found to be predictive of need for neoaortic arch reintervention after multivariate analysis. Echocardiographic and catheterization gradients were found to have poor correlation with one another. A peak gradient of 26 mmHg or greater by echocardiography and a peak-to-peak gradient of 8.5 mmHg or greater by catheterization after the Norwood but prior to the Glenn are predictive of need for neoaortic reintervention through the time of the Glenn hospitalization.

Recoarctation After Norwood I Procedure for Hypoplastic Left Heart Syndrome: Impact of Patch Material

BACKGROUND

The development of recoarctation after the Norwood I procedure is a known complication in patients with hypoplastic left heart syndrome (HLHS).

METHODS

We reviewed data on 194 consecutive patients with HLHS who underwent the Norwood I procedure between 2000 and 2015. All patients who survived until the second stage of the procedure were included. Recoarctation was defined by the need for intervention, either catheter based or surgical. The aim of our study was to determine if the patch material used for the initial arch reconstruction had an influence on the development of recoarctation.

RESULTS

The study population consisted of 145 patients. The patch material used for aortic arch reconstruction was either a homograft (n = 87), autologous pericardium (n = 23), equine pericardium (n = 28), or other material (n = 7). Recoarctation was documented in 27 patients (18%) at a median time of 4.3 months (range, 1 to 28 months) after completion of Norwood I. Freedom from recoarctation was 85% ± 4%, 86% ± 7%, and 30% ± 22% at 2 years for homograft, autologous pericardium, and equine pericardium, respectively. Thirty-six percent of patients with equine pericardium exhibited recoarctation, significantly more than homograft patch (p < 0.01) or autologous pericardium (p = 0.002). Treatment for recoarctation was percutaneous balloon angioplasty in 19 patients, stent implantation in 3, and operative enlargement of the aortic arch in 5. On univariate analysis, arch reconstruction with equine pericardium was the only risk factor for recoarctation (hazard ratio, 6.0; 95% confidence interval, 2.6-14; p < 0.01).

CONCLUSIONS

The patch material used for reconstruction of the aortic arch in HLHS influences the rate of recoarctation following the Norwood I procedure. Equine pericardium cannot be recommended.

Surgical Management of Vascular Stents in Pediatric Cardiac Surgery: Clues for a Staged Partnership

Complex cases undergo step surgical and percutaneous procedures, including stent deployment. Concerns arise on stent removal at latest surgery. Our initial experience is presented. Forty-six stents in 35 patients were partially or totally removed at surgery. Univentricular heart was diagnosed in 20 patients. Stents were previously deployed in: ductus (6), right ventricle outflow tract (12), atrial septal defect (4), right pulmonary artery (4), left pulmonary artery (16), inferior vena cava (2), superior vena cava (1) and ascending aorta (1). Surgical procedures performed: 9 transplants, 6 Fontan, 4 Glenn, 1 comprehensive repair (Norwood + Glenn), 1 Glenn takedown, 8 conduit replacement, 2 Fallot, 2 Rastelli, 1 ventricular septal defect closure and 1 iatrogenic aortopulmonary window. Five ductal stents were clipped. Eleven stents in right ventricle, four ones in atrial septal defect, two in right pulmonary artery, seven in the left pulmonary artery and two in inferior vena cava were completely removed. Two stents in right pulmonary artery, one in superior vena cava, one in ascending aorta and nine in the left pulmonary artery were partially retrieved. Handling the stents in ductus, right ventricle and atrial septal defect was straightforward. On the contrary, stent removal in the ductus (comprehensive case), pulmonary branches, both vena cavae or aorta required short periods of deep hypothermia with circulatory arrest. Surgery over stents is increasing in complex, step procedures. Univentricular hearts are most prevalent. Congenital transplant surgery faces new challenges. Stent removal at the time of surgery may require deep hypothermic circulatory arrest.