Outcomes of patients born with single-ventricle physiology and aortic arch obstruction: the 26-year Melbourne experience

EASL-ERN position paper on liver involvement in patients with Fontan-type circulation

Fontan-type surgery is the final step in the sequential palliative surgical treatment of infants born with a univentricular heart. The resulting long-term haemodynamic changes promote liver damage, leading to Fontan-associated liver disease (FALD), in virtually all patients with Fontan circulation. Owing to the lack of a uniform definition of FALD and the competitive risk of other complications developed by Fontan patients, the impact of FALD on the prognosis of these patients is currently debatable. However, based on the increasing number of adult Fontan patients and recent research interest, the European Association for The Study of the Liver and the European Reference Network on Rare Liver Diseases thought a position paper timely. The aims of the current paper are: (1) to provide a clear definition and description of FALD, including clinical, analytical, radiological, haemodynamic, and histological features; (2) to facilitate guidance for staging the liver disease; and (3) to provide evidence- and experience-based recommendations for the management of different clinical scenarios.

Diagnosis and surgical outcomes of coarctation of the aorta in pediatric patients: a retrospective study

BACKGROUND

Coarctation of the aorta (CoA) is a common congenital cardiovascular malformation, and improvements in the diagnostic process for surgical decision-making are important. We sought to compare the diagnostic accuracy of transthoracic echocardiography (TTE) with computed tomographic angiography (CTA) to diagnose CoA.

METHODS

We retrospectively reviewed 197 cases of CoA diagnosed by TTE and CTA and confirmed at surgery from July 2009 to August 2019.

RESULTS

The surgical findings confirmed that 19 patients (9.6%) had isolated CoA and 178 (90.4%) had CoA combined with other congenital cardiovascular malformations. The diagnostic accuracy of CoA by CTA was significantly higher than that of TTE (χ2 = 6.52, p = 0.01). In contrast, the diagnostic accuracy of TTE for associated cardiovascular malformations of CoA was significantly higher than that of CTA (χ2 = 15.36, p < 0.0001). Infants and young children had more preductal type of CoA, and PDA was the most frequent cardiovascular lesion associated with CoA. The pressure gradient was significantly decreased after the first operation, similar at 6 months, 1 year, and 3 years follow-ups by TTE.

CONCLUSIONS

CTA is more accurate as a clinical tool for diagnosing CoA; however, TTE with color Doppler can better identify associated congenital cardiovascular malformations. Therefore, combining TTE and CTA would benefit clinical evaluation and management in patients suspected of CoA. TTE was valuable for post-operation follow-up and clinical management.

Utility of Conventional but Late Pulmonary Artery Banding in Complex Cyanotic Congenital Heart Disease in a Toddler - A Single Case Scenario

Newborns with untreated single ventricles develop pulmonary vascular diseases early in their lives. At that age, during the first eight weeks after birth, clinicians perform pulmonary artery (PA) banding to reduce the blood flow to the lung, decreasing the likelihood of future high vascular resistance or pressure. PA banding is also considered an initial stage in the process of single ventricle palliation procedures. We report a case of a 16-month-old toddler (7 kg) with room air saturation of 82%, diagnosed with tricuspid valve atresia, large atrial and ventricular septal defect, and hypoplastic right ventricle with severe pulmonary arterial hypertension. The baby underwent a successful surgical procedure of PA banding and was discharged after 13 days of hospital stay with a room air saturation of 89%. This case highlighted the benefit of PA banding beyond the stipulated period.

A shunt decision-making protocol in the surgical palliation of hypoplastic left heart syndrome from 2004 to 2016

OBJECTIVES

The aim of this study was to study the impact of a decision-making protocol for shunt type in the Norwood procedure for hypoplastic left heart syndrome. Our cohort extends from 2004 to 2016. In era 1 (pre-2008), there was no policy for the choice of Norwood shunt. In era 2 (post-2008), a standard protocol was implemented. The right ventricle (RV)-to-pulmonary artery conduit was utilized for low-birth weight patients (<2.5 kg). The right modified Blalock-Taussig Shunt (RBTS) was constructed for normal birth weight patients.

METHODS

The records of 133 consecutive operative patients with hypoplastic left heart syndrome anatomy between 2004 and 2016 were retrospectively reviewed. Survival risk factors were analysed using the Cox proportional hazards risk model.

RESULTS

The Norwood procedure was performed at a mean age of 2.9 ± 1.9 days. Bidirectional cavopulmonary shunt was performed at a median age of 99 days (interquartile range 91-107). In era 1, 38.6% (22/57) of patients received the RBTS and 61.4% (35/57) of patients received the RV-to-pulmonary artery conduit. In era 2, 86.8% (66/76) of patients received the RBTS and 13.2% (10/76) of patients received the RV-to-pulmonary artery conduit. The actuarial survival to Fontan was 72.2% (96/133). Era 1 patients were more likely to die within the 1st year (hazard ratio = 2.310, P = 0.025).

CONCLUSIONS

The shunt protocol may improve outcomes in high-risk patients, and we have demonstrated the reliability of the RBTS in low-risk patients. The short- and mid-term outcomes of our Norwood population justify the continued efforts to improve surgical and perioperative management.

Pulse oximetry screening for critical congenital heart defects in Ontario, Canada: a cost-effectiveness analysis

OBJECTIVE

Previously conducted cost-effectiveness analyses of pulse oximetry screening (POS) for critical congenital heart defects (CCHDs) have shown it to be a cost-effective endeavour, but the geographical setting of Ontario in relation to its vast yet sparsely populated regions presents unique challenges. The objective of this study was to estimate the cost-effectiveness of POS for CCHD in Ontario, Canada.

METHODS

A cost-effectiveness analysis, comparing POS to no POS, was conducted from the Ontario healthcare payer perspective using a Markov model. The base case was defined as a well-appearing newborn at 24 h of age. Outcome measures, including quality-adjusted life months (QALMs), lifetime costs, and incremental cost-effectiveness ratios (ICER) [ΔCost/ΔQALMs], were calculated over a lifetime horizon. All outcomes were discounted at 1.5% per year. Cost-effectiveness was assessed using an a priori ICER threshold of CAD$4166.67 per QALM (equivalent to CAD$50,000 per quality-adjusted life year). Deterministic and probabilistic sensitivity analyses were conducted to assess parameter uncertainty.

RESULTS

Implementation of POS is expected to lead to timely diagnosis of 51 CCHD cases annually. The incremental cost of performing POS was estimated to be $27.27 per screened individual, with a gain of 0.02455 QALMs. This yielded an ICER of CAD$1110.79 per QALM, well below the pre-determined threshold. The probabilistic sensitivity analysis estimated a 92.3% chance of routine implementation of POS being cost-effective.

CONCLUSION

Routine implementation of POS for CCHD in Ontario is expected to be cost-effective.

Utility of late pulmonary artery banding in single-ventricle physiology: A mid-term follow-up

Background:

The standard first stage palliation for univentricular heart with unrestricted pulmonary blood flow (PBF) is surgical pulmonary artery (PA) banding for which the ideal age is within the first 8 weeks of life. This study aimed to look for the utility of PA band done beyond 3 months of age for patients presenting beyond the stipulated period.

Materials and Methods:

This is a retrospective analysis of the outcome of twenty patients with single ventricle (SV) physiology with unrestricted PBF who presented late and were selected on the basis of clinical, radiological, and echocardiographic parameters for PA banding.

Results:

The median age of the patients was 5.5 months (3.5–96 months), and the median body weight was 4.7 kg (3.2–22.0 kg). The patients were divided into three groups as follows: ten patients between 3 and 6 months of age (Group A), seven patients between 6 months to 1 year of age (Group B), and three patients > 1 year of age with additional features of pulmonary venous hypertension (Group C). The mean reduction of PA pressures following PA band was 60.9%, 48.8%, and 58.3% and the mean fall in oxygen saturation was 10.4%, 8.0%, and 6.6% in the three groups, respectively. The postoperative mortality rate was 10%. The mean follow up duration was 13.5 months (7–23 months). There was a statistically significant improvement in weight for age Z scores following PA band (P = 0.0001). On follow up cardiac catheterization, the mean PA pressures were 16.6 (±3.6), 22.7 (±5.7), and 33.3 (±12.4) mmHg, respectively, in the three groups, and the mean pulmonary vascular resistance index was 1.86 (±0.5), 2.45 (±0.7), and 3.5 (±1.6) WU.m2, respectively. Subsequently, seven patients in Group A, three patients in Group B, and one patient from Group C underwent successful bidirectional Glenn (BDG) surgery.

Conclusions:

Late PA band in selected patients with SV physiology can have definite benefit in terms of correction of heart failure symptoms and subsequent conversion to BDG and can potentially change the natural history of disease both in terms of survival and quality of life.

High prevalence of early arch reobstruction after arch repair in patients with anomalous right subclavian artery

OBJECTIVES

Having an anomalous right subclavian artery has been quoted to be a risk factor for early and late adverse events. We wanted to determine the rate of adverse outcomes in patients who have undergone arch repair with an associated anomalous right subclavian artery.

METHODS

The follow-up of 76 patients, with an anomalous right subclavian artery, who underwent arch repair at a single institution for various indications between 1981 and 2017 was reviewed.

RESULTS

There were 12 patient deaths. Twenty-three patients required an aortic arch reintervention (17 surgeries, 2 of which were indicated for bronchial obstruction). At last follow-up, 8 of 54 surviving patients (15%) had arch reobstruction (peak gradient >25 mmHg or reintervention). Freedom from aortic arch obstruction at 10 and 15 years was 51% [95% confidence interval (CI) 36-65%] and 35% (95% CI 19-51%), respectively. Neither the complete resection of the adjacent ridge nor the detachment and reimplantation of the anomalous subclavian vessel seemed to have an impact on the rate of reobstruction [hazard ratio (HR) 1.6, 95% CI 0.77-3.5; P = 0.2 and HR 0.61, 95% CI 0.083-4.5; P = 0.6, respectively].

CONCLUSIONS

Patients with an anomalous right subclavian artery are at risk of arch reobstruction necessitating reintervention but long-term follow-up was unable to demonstrate the mechanism of this obstruction in patients with this anomaly.

Reintervention and survival in 1428 patients in the Australian and New Zealand Fontan Registry

Objective

Patients undergoing single-ventricle palliation have experienced significant improvement in survival in the recent era. However, a substantial proportion of these patients undergo reoperations. We performed a review of the Australia and New Zealand (ANZ) Fontan Registry to determine the overall reintervention and reoperative burden in these patients.

Methods

A retrospective longitudinal cohort study was performed using data from patients who underwent a Fontan operation between 1975 and 2016 from the ANZ Fontan Registry. The data obtained included Fontan operation, reinterventions and most recent follow-up status. We examined the type and timing of reinterventions and survival.

Results

Of the 1428 patients identified, 435 (30%) underwent at least one reintervention after the Fontan operation: 110 patients underwent early reintervention and 413 underwent late reinterventions. Excluding Fontan conversion and transplantation, 220 patients underwent at least one interventional procedure and 209 patients underwent at least one reoperation. Fenestration closure and pacemaker-related procedures were the most common catheter and surgical interventions, respectively. The cumulative incidence of reintervention following Fontan was 23%, 37% and 55% at 10, 20 and 30 years, respectively. Survival and freedom from failure were worse in patients requiring later reintervention after Fontan surgery (51% vs 83% and 42% vs 69%, respectively at 30 years, p<0.001). This difference persisted after excluding pacemaker-related procedures (p<0.001). Operative mortality for non-pacemaker late reoperations after Fontan was 6%.

Conclusions

A substantial proportion of Fontan patients require further intervention to maintain effective single-ventricle circulation. Patients undergoing reoperation after Fontan have higher rates of mortality and failure, despite intervention.

Echocardiographic arterial measurements in complex congenital diseases before bidirectional Glenn: comparison with cardiovascular magnetic resonance imaging

Aims

This study sought to investigate diagnostic accuracy of echocardiographic measures of great vessels in patients before bidirectional cavopulmonary connection (BCPC) compared with cardiovascular magnetic resonance (CMR).

Methods and results

Seventy-two patients (61% after Norwood operation) undergoing BCPC between 2007 and 2012 were assessed pre-operatively using echocardiography and CMR. Bland-Altman analysis and correlation coefficients were used for comparison of echocardiography and CMR measurements. Sensitivity, specificity, and positive and negative predictive values were calculated to assess the ability of echocardiography to detect vessel stenosis. Twenty-four percent of all vessel measurements could not be made by echocardiography due to poor image quality. Acquisition of unsatisfactory images was higher in non-sedated patients. Although there was a reasonable correlation (0.68-0.90) and low bias (-0.8 to 0.5), there were wide limits of agreement between echocardiography and CMR demonstrating poor agreement. Sensitivity and specificity for pulmonary branches were moderate [sensitivity for right pulmonary artery (RPA) 67%, left pulmonary artery (LPA) 54%, specificity for RPA 65%, LPA 72%] with low levels of accuracy (RPA and LPA 42%). Sensitivity, specificity, and accuracy were better for aorta (82, 86, and 63%, respectively).

Conclusion

This study demonstrates modest agreement between echocardiographic and CMR measures of vessel diameter and stenosis detection. Approximately a quarter of all vessel segments could not be measured using echocardiography due to poor image quality, which was significantly lower in non-sedated patients. These findings show that echocardiography cannot substitute CMR for reliable identification of great vessel stenoses in complex patients prior to the BCPC, particularly those with Blalock-Taussig shunts.

Palliation Outcomes of Neonates Born With Single-Ventricle Anomalies Associated With Aortic Arch Obstruction

BACKGROUND

The two most common surgical strategies for the treatment of neonates born with single-ventricle anomalies associated with aortic arch obstruction are the Norwood operation and pulmonary artery banding plus coarctation repair (PAB+COA). We reviewed characteristics and outcomes of neonates who underwent those two surgical strategies at our institution.

METHODS

Between 2002 and 2012, 94 neonates with a single ventricle and aortic arch obstruction (excluding hypoplastic left heart syndrome) underwent Norwood (n = 65) or PAB+COA (n = 29). Outcomes were parametrically modeled, and risk factors associated with early and late death were analyzed.

RESULTS

Competing-risks analysis showed that, at 2 years after the operation, 24% of patients had died or received transplantation and 75% had undergone a Glenn shunt. At 5 years after the Glenn shunt, 10% of patients had died or received transplantation, 62% had undergone Fontan, and 28% were alive awaiting Fontan. Overall 8-year survival was 70%. Outcomes after Norwood included extracorporeal membrane oxygenation use in 9 (14%), unplanned reoperation in 13 (20%), hospital death in 10 (15%), and interstage death in 8 (12%), with 8-year survival of 66%. Outcomes after PAB+COA included extracorporeal membrane oxygenation use in 1 (3%), unplanned reoperation in 9 (30%), hospital death in 1 (3%), and interstage death in 3 (10%), with 8-year survival of 76%. There was an association trend between underlying anatomy and survival (hazard ratio [HR], 2.1; 95% confidence interval [CI], 0.9 to 4.7; p = 0.087). On multivariable analysis, factors associated with death were extracorporeal membrane oxygenation use (HR, 5.5; 95% CI, 1.9 to 15.9; p = 0.002), genetic syndromes/extracardiac anomalies (HR, 3.5; 95% CI, 1.5 to 8.2; p = 0.003), and weight of 2.5 kg or less (HR, 3.0; 95% CI, 1.3 to 7.2; p = 0.012).

CONCLUSIONS

Anatomic and patient characteristics influence palliation outcomes in neonates born with single-ventricle anomalies associated with aortic arch obstruction. Although the Norwood operation is applicable in most of these patients, the PAB+COA strategy is a valid alternative in well-selected patients.

Influence of Morphology and Initial Surgical Strategy on Survival of Infants With Tricuspid Atresia

BACKGROUND

Tricuspid atresia (TA) is a heterogeneous single-ventricle anomaly in which initial presentation and, consequently, timing and mode of palliation vary based on morphology and degree of pulmonary or systemic outflow obstruction. We report current era palliation outcomes and examine whether morphologic and, subsequently, surgical factors influence survival.

METHODS

From 2002 to 2012, 105 infants with TA underwent surgical palliation. Competing risks analyses modeled events after first-stage surgery (Glenn versus death) and after Glenn (Fontan versus death) and examined risk factors affecting outcomes.

RESULTS

Seventy-eight patients (74%) required neonatal first-stage palliation, including modified Blalock-Taussig shunt (n = 46, 44%), Norwood (n = 18, 17%), and pulmonary artery band (n = 14, 13%), whereas 27 (26%) received primary Glenn as their initial surgery. Hospital mortality was 5 patients (4.8%). Competing risks models showed that by 1 year after first-stage surgery, 15% of patients had died and 83% had undergone Glenn. By 5 years after Glenn, 2% of patients had died and 80% had undergone Fontan. Overall 8-year survival was 84%. On multivariable analysis, risk factors for mortality were genetic/extracardiac anomalies (hazard ratio 7.0, 95% confidence interval: 2.4 to 20.6, p < 0.001) and pulmonary atresia (hazard ratio 4.4, 95% confidence interval: 1.6 to 12.2, p = 0.004). Survival was not affected by initial palliation type (p = 0.36), ventriculoarterial discordance (p = 0.25), systemic outflow obstruction (p = 0.84), or arch obstruction (p = 0.62).

CONCLUSIONS

Despite morphologic and physiologic variations necessitating different palliative sequences, multistage palliation outcomes of various TA subtypes are comparable and generally good, with the exception of patients with associated genetic/extracardiac anomalies. The bulk of mortality is interstage, indicating continued opportunity for improvement in monitoring and managing patients during this critical period.

Current Outcomes of the Norwood Operation in Patients With Single-Ventricle Malformations Other Than Hypoplastic Left Heart Syndrome

Background:

Subsequent to increased experience with the Norwood operation in children with hypoplastic left heart syndrome (HLHS), its application has expanded to allow palliation of single-ventricle (SV) malformations other than HLHS. We describe current palliation outcomes in this group of SV patients.

Methods:

Between 2002 and 2012, 65 of the 303 Norwood operations were performed in non-HLHS SV patients. Competing risk analysis modeled events after Norwood and after subsequent Glenn and examined risk factors affecting outcomes.

Results:

Competing risk analysis showed that one year following Norwood, 24% of patients had died or received transplantation, 72% had undergone Glenn, and 4% were alive awaiting Glenn/Kawashima. Five years following Glenn, 9% of patients had died, 68% had undergone Fontan, and 23% were alive awaiting Fontan. Overall seven-year survival following Norwood was 68%. On multivariable analysis, mortality risk factors were unplanned cardiac reoperation (hazard ratio [HR]: 4.0 [1.5-10.6], P = .006), right dominant ventricle morphology (HR: 3.3 [1.3-8.3], P = .012), and postoperative extracorporeal membrane oxygenation (HR: 3.1 [1.1-9.0], P = .035).

Conclusions:

Operative death and interstage mortality continue to be problematic following Norwood palliation for non-HLHS SV variants. Outcomes seem comparable to those reported for HLHS, however they are influenced by underlying pathology; children with dominant left ventricle morphology (tricuspid atresia and double inlet left ventricle) have superior survival compared to those with dominant right ventricle morphology (mitral atresia, unbalanced atrioventricular septal defect, and most patients with atrial isomerism). Unplanned reoperations for technical imperfections diminish survival. Large multicenter studies might be warranted to better identify high-risk patients and provide guidance toward improving their survival.

Fetal aortic valvuloplasty for evolving hypoplastic left heart syndrome: postnatal outcomes of the first 100 patients

BACKGROUND

Fetal aortic valvuloplasty can be performed for severe midgestation aortic stenosis in an attempt to prevent progression to hypoplastic left heart syndrome (HLHS). A subset of patients has achieved a biventricular (BV) circulation after fetal aortic valvuloplasty. The postnatal outcomes and survival of the BV patients, in comparison with those managed as HLHS, have not been reported.

METHODS AND RESULTS

We included 100 patients who underwent fetal aortic valvuloplasty for severe midgestation aortic stenosis with evolving HLHS from March 2000 to January 2013. Patients were categorized based on postnatal management as BV or HLHS. Clinical records were reviewed. Eighty-eight fetuses were live-born, and 38 had a BV circulation (31 from birth, 7 converted after initial univentricular palliation). Left-sided structures, namely aortic and mitral valve sizes and left ventricular volume, were significantly larger in the BV group at the time of birth (P<0.01). After a median follow-up of 5.4 years, freedom from cardiac death among all BV patients was 96±4% at 5 years and 84±12% at 10 years, which was better than HLHS patients (log-rank P=0.04). There was no cardiac mortality in patients with a BV circulation from birth. All but 1 of the BV patients required postnatal intervention; 42% underwent aortic or mitral valve replacement. On the most recent echocardiogram, the median left ventricular end-diastolic volume z score was +1.7 (range, -1.3 to +8.2), and 80% had normal ejection fraction.

CONCLUSIONS

Short- and intermediate-term survival among patients who underwent fetal aortic valvuloplasty and achieved a BV circulation postnatally is encouraging. However, morbidity still exists, and ongoing assessment is warranted.