Long-term outcomes of single-ventricle palliation for unbalanced atrioventricular septal defects: Fontan survivors do better than previously thought

Pulmonary Artery Banding and Arch Repair vs Norwood for Unbalanced Atrioventricular Canal Defect

BACKGROUND

The outcomes of single-ventricle palliation in unbalanced atrioventricular canal defect with coarctation of aorta (uAVC+CoA) have not been well studied. Systemic ventricle outflow tract obstruction has a propensity to develop in these patients after aortic arch repair with pulmonary artery banding (arch-PAB), which may adversely affect survival and Fontan candidacy.

METHODS

A retrospective review was performed of patients who underwent single-ventricle palliation for uAVC+CoA from 2000 to 2022. Patients were divided into 2 groups based on initial palliation: (1) arch-PAB and (2) Norwood procedure. Demographic and clinical characteristics were analyzed and compared along with survival data.

RESULTS

Stage 1 palliation for uAVC+CoA was performed in 41 patients. Arch-PAB was performed in 14 infants and Norwood in 27 infants. Arch-PAB patients had more chromosomal abnormalities (28.6 vs 7.4%, P < .009) and less severe systemic ventricle outflow tract obstruction on baseline echocardiogram (0.0 vs 70.4%, P < .001). Survival to stage 3 palliation was lower for the arch-PAB group (28.6% vs 66.6%, P = .02). Arch-PAB remained a significant risk factor for mortality (hazard ratio, 2.93; 95% CI, 1.05-8.53; P = .04) after adjusting for chromosomal abnormalities and atrioventricular valve regurgitation. After arch-PAB, systemic ventricle outflow tract obstruction was diagnosed in 13 of 14 patients. Echocardiography underestimated the degree of outflow tract obstruction in 10 of 13 arch-PAB patients.

CONCLUSIONS

Arch-PAB has worse outcomes than Norwood for uAVC+CoA. Systemic ventricle outflow tract obstruction develops in almost all patients after arch-PAB. Outflow tract obstruction is underestimated by the echocardiogram and requires a high index of suspicion, along with advanced imaging, to ensure timely diagnosis and management.

Impact of Atrioventricular Valve Intervention at Each Stage of Single Ventricle Palliation

Background: Significant atrioventricular valve dysfunction can be associated with mortality or need for transplant in functionally univentricular heart patients undergoing staged palliation. The purposes of this study are to characterize the impact of concomitant atrioventricular valve intervention on outcomes at each stage of single ventricle palliation and to identify risk factors associated with poor outcomes in these patients. Methods: The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried for functionally univentricular heart patients undergoing single ventricle palliation from 2013 through 2022. Separate analyses were performed on cohorts corresponding to each stage of palliation (1: initial palliation; 2: superior cavopulmonary anastomosis; 3: Fontan procedure). Bivariate analysis of demographics, diagnoses, comorbidities, preoperative risk factors, operative characteristics, and outcomes with and without concomitant atrioventricular valve intervention was performed. Multiple logistic regression was used to identify predictors associated with operative mortality or major morbidity. Results: Concomitant atrioventricular valve intervention was associated with an increased risk of operative mortality or major morbidity for each cohort (cohort 1: 62% vs 46%, P < .001; cohort 2: 37% vs 19%, P < .001; cohort 3: 22% vs 14%, P < .001). Black race in cohort 1 (odds ratio [OR] 3.151, 95% CI 1.181-9.649, P = .03) and preterm birth in cohort 2 (OR 1.776, 95% CI 1.049-3.005, P = .032) were notable predictors of worse morbidity or mortality. Conclusions: Concomitant atrioventricular valve intervention is a risk factor for operative mortality or major morbidity at each stage of single ventricle palliation. Several risk factors are associated with these outcomes and may be useful in guiding decision-making.

Heart Transplantation after Univentricular Palliation: Improved Outcomes and Increased Complexity

AIM

Heart transplantation (HT) in patients with failing univentricular circulation is often challenging. This is compounded by the ever-increasing number of patients with prior Norwood-type reconstruction of the aorta, large aortic root, and often dense adhesions from multiple prior operations. We aimed to elucidate differences in outcomes of HT in patients with prior univentricular palliations, with and without prior Norwood-type aortic arch reconstruction (ArchRec).

METHODS

All patients who underwent HT for failed univentricular palliation during the 1990-2022 period were included in the study.

RESULTS

Of 45 patients, 18 had undergone ArchRec. Hospital mortality improved in the recent era (17.4% before 2006 vs 0% after 2006; p=0.11), despite a higher proportion of patients with ArchRec (17.4% before 2006 vs 60.8% after 2006, p=0.002). Patients with ArchRec had a higher number of prior cardiac surgeries (4.1±1.5 vs 3.2±1.3, p=0.04), longer cardiopulmonary bypass time (320±23 vs 242±21 min, p=0.02), more concomitant arch reconstruction (33.3% vs 0%, p=0.02), greater need for post-HT extracorporeal membrane oxygenation (33.3% vs 3.7%; p=0.01) and longer hospital stay (37.1±30.5 days vs 23.6±11.8 days, p=0.04). Freedom from death or retransplantation for all patients was 91%, 73%, 67%, and 53% at 1, 5, 10, and 15-years, respectively. Prior ArchRec, Fontan procedure, and earlier eras were not risk factors for death.

CONCLUSIONS

The outcomes of HT after univentricular palliation have improved in recent times and low operative mortality can be achieved. Despite increased complexity, good similar outcomes can be achieved in patients with and without prior arch reconstruction regardless of the palliation stage.

Cleft closure and other predictors of contemporary outcomes after atrioventricular canal repair in patients with parachute left atrioventricular valve

OBJECTIVES

Parachute left atrioventricular valve (LAVV) complicates atrioventricular septal defect (AVSD) repair. We evaluate outcomes of AVSD patients with parachute LAVV and identify risk factors for adverse outcomes.

METHODS

We evaluated all patients undergoing repair of AVSD with parachute LAVV from 2012 to 2021. The primary outcome was a composite of time-to-death, LAVV reintervention and development of greater than or equal to moderate LAVV dysfunction (greater than or equal to moderate LAVV stenosis and/or LAVV regurgitation). Event-free survival for the composite outcome was estimated using Kaplan-Meier methodology and competing risks analysis. Cox proportional hazards regression was used to identify predictors of the primary outcome.

RESULTS

A total of 36 patients were included with a median age at repair of 4 months (interquartile range 2.3-5.5 months). Over a median follow-up of 2.6 years (interquartile range 1.0-5.6 years), 6 (17%) patients underwent LAVV reintervention. All 6 patients who underwent LAVV reintervention had right-dominant AVSD. Sixteen patients (44%) met the composite outcome, and all did so within 2 years of initial repair. Transitional AVSD (versus complete), prior single-ventricle palliation, leaving the cleft completely open and greater than or equal to moderate preoperative LAVV regurgitation were associated with a higher risk of LAVV reintervention in univariate analysis. In multivariate analysis, leaving the cleft completely open was associated with the composite outcome.

CONCLUSIONS

Repair of AVSD with parachute LAVV remains a challenge with a significant burden of LAVV reintervention and dysfunction in medium-term follow-up. Unbalanced, right-dominant AVSDs are at higher risk for LAVV reintervention. Leaving the cleft completely open might independently predict poor overall outcomes and should be avoided when possible.

CLINICAL TRIAL REGISTRATION NUMBER

IRB-P00041642.

Therapy of Patients with Cardiac Malposition

Positional abnormalities per se do not require treatment, but in their place, the accompanying pulmonary pathology in dextroposition patients and pathophysiologic hemodynamic abnormalities resulting from multiple defects in patients with cardiac malposition should be the focus of treatment. At the time of the first presentation, treating the pathophysiologic aberrations caused by the defect complex, whether it is by improving the pulmonary blood flow or restricting it, is the first step. Some patients with simpler or single defects are amenable to surgical or transcatheter therapy and should be treated accordingly. Other associated defects should also be treated appropriately. Biventricular or univentricular repair dependent on the patient's cardiac structure should be planned. Complications in-between Fontan stages and after conclusion of Fontan surgery may occur and should be promptly diagnosed and addressed accordingly. Several other cardiac abnormalities unrelated to the initially identified heart defects may manifest in adulthood, and they should also be treated.

Atrioventricular septal defect in Fontan circulation: Right ventricular dominance, not valve surgery, adversely affects survival

OBJECTIVE

The effect of ventricular dominance and previous atrioventricular valve (AVV) surgery on patient outcomes after Fontan operation remains unclear. We sought to determine the effect of ventricular dominance and previous AVV surgery on transplantation-free survival and long-term AVV competency in patients with atrioventricular septal defect (AVSD) and Fontan circulation.

METHODS

We conducted a retrospective study of 1703 patients in the Australia and New Zealand Fontan Registry, who survived Fontan operation between 1987 and 2021.

RESULTS

Of 174 patients with AVSD, 60% (105/174) had right ventricular (RV) dominance and 40% (69/174) had left ventricular (LV) dominance. The cumulative incidence of moderate or greater AVV regurgitation at 25 years after Fontan operation in patients with LV dominance was 56% (95% CI, 35%-72%), compared with 54% (95% CI, 40%-67%) in patients with RV dominance (P = .6). Nonetheless, transplantation-free survival at 25 years in patients with LV dominance was 94% (95% CI, 86%-100%), compared with 67% (95% CI, 52%-87%) in patients with RV dominance (hazard ratio, 5.9; 95% CI, 1.4-25.4; P < .01). Of note, transplantation-free survival was not different in patients who underwent AVV surgery before or at Fontan completion compared with those who did not (15 years: 81% [95% CI, 62%-100%] vs 88% [95% CI, 81%-95%]; P = .3).

CONCLUSIONS

In patients with AVSD and Fontan circulation the rate of moderate or greater common AVV regurgitation is similar in those with LV and RV dominance. RV dominance, rather than previous AVV surgery, is a risk factor for death or transplantation.

Transcatheter Interventions in Patients With Adult Congenital Heart Disease

Patients with congenital heart disease now live well into adulthood because of advances in surgical techniques, improvements in medical management, and the development of novel therapeutic agents. As patients grow older into adults with congenital heart disease, many require catheter-based interventions for the treatment of residual defects, sequelae of their initial repair or palliation, or acquired heart disease. The past 3 decades have witnessed an exponential growth in both the type and number of transcatheter interventions in patients with congenital heart disease. With improvements in medical technology and device design, including the use of devices designed for the treatment of acquired valve stenosis or regurgitation, patients who previously would have required open-heart surgery for various conditions can now undergo percutaneous cardiac catheter-based procedures. Many of these procedures are complex and occur in complex patients who are best served by a multidisciplinary team. This review aims to highlight some of the currently available transcatheter interventional procedures for adults with congenital heart disease, the clinical outcomes of each intervention, and any special considerations so that the reader may better understand both the procedure and patients with adult congenital heart disease.

National outcomes of the Fontan operation with endocardial cushion defect

BACKGROUND

The traditional outcomes of the Fontan operation (FO) in endocardial cushion defect (ECD) patients have been suboptimal. Previous studies have been limited by the smaller number of ECD patients, longer study period with an era effect, and do not directly compare short-term outcomes of FO in ECD patients with non-ECD patients. Our study aims to address these shortcomings.

METHODS

A retrospective analysis of the Kids Inpatient Database (2009, 2012, and 2016) for the FO was done. The groups were divided into those who underwent FO with ECD as compared to non-ECD diagnosis. The data were abstracted for demographics, clinical characteristics, and operative outcomes. Standard statistical tests were used.

RESULTS

Three thousand three hundred eighty patients underwent the FO of which 360 patients (11%) were FO-ECD. ECD patients were more likely to have Down syndrome, Heterotaxy syndrome, transposition/DORV, and TAPVR as compared to non-ECD patients. FO-ECD had a higher discharge-mortality (2.84% vs. 0.45%, p = .04). The length of stay (16 vs. 13 days, p = .05) and total charges incurred ($283, 280 vs. $234, 106, p = .03) for the admission were higher in the FO-ECD as compared to non-ECD patients. In multivariable analysis, ECD diagnosis, cardiac arrest, acute kidney injury, and postoperative hemorrhage were predictors of mortality.

CONCLUSION

Contemporary outcomes for FO are excellent with very low overall operative mortality. However, the outcomes in ECD patients are inferior with higher operative mortality than in non-ECD patients. The occurrence of postoperation complications and a diagnosis of ECD were predictive of a negative outcome.

National Fontan Operation short-term outcomes at or below 2-years-of-age compared to older than 2-years-of-age

INTRODUCTION

Opinion is divided about optimal early timing of the Fontan Operation (FO). While some studies have suggested 3 years-of-age, others have shown good outcomes below 2 years-of-age. We analyzed the impact of age ≤2 years as compared age >2 years on short-term outcome of the FO using a large national database.

METHODS

A retrospective analysis of the Kids Inpatient Database (2009-16) for the FO was done. The groups were divided into those who underwent FO at age ≤2 years (Early FO [EF]) as compared to age >2 years (Late FO [LF]). The data was abstracted for demographics, clinical characteristics, and operative outcomes. Standard statistical tests were used.

RESULTS

A total of 3381 patients underwent FO during this period of which 1482 (44%) were EF. The mean ages of the EF and LF were 1.6 and 4.3, respectively (p < .001). LF were more likely to be non-White, female, and have Heterotaxy syndrome. HLHS was more common in EF. There was no difference in the discharge mortality, length of stay, disposition (majority went home), and mean total charges incurred. The overall discharge mortality was low at 0.7% (24/3381). In multivariate analysis: cardiac arrest, acute kidney injury, mechanical ventilation >96 h, endocardial cushion defect and non-White ethnicity were predictors of a mortality and not age.

CONCLUSION

Contemporary outcomes for FO are excellent with equivalent short-term outcomes in both the age groups. Occurrence of postoperative complications, non-White ethnicity and endocardial cushion defect diagnosis were predictive of a negative outcome.

The Improved Prognosis of Hypoplastic Left Heart: A Population-Based Register Study of 343 Cases in England and Wales

Background: Hypoplastic Left Heart Syndrome (HLHS) is a severe congenital heart defect (CHD) characterised by the underdevelopment of the left side of the heart with varying levels of hypoplasia of the left atrium, mitral valve, left ventricle, aortic valve and aortic arch. In the UK, age 12 survival for cases born between 1991 and 1993 was 21%. UK survival estimates corresponding to cases born between 2000 and 2015 were improved at 56%, but survival was examined up to age five only. Contemporary long-term survival estimates play a crucial role in counselling parents following diagnosis. The aim of this study was to report survival estimates up to age 15 for children born with HLHS or hypoplastic left ventricle with additional CHD in England and Wales between 1998 and 2012. Methods: Cases of HLHS notified to four congenital anomaly registers in England and Wales during 1998-2012, matched to Office for National Statistics mortality information, were included. Kaplan-Meier survival estimates to age 15 were reported. Cox regression models were fitted to examine risk factors for mortality. Results: There were 244 cases of HLHS and 99 cases of hypoplastic left ventricle co-occurring with other CHD, with traced survival status. Kaplan-Meier survival estimates for HLHS were 84.4% at age 1 week, 76.2% at 1 month, 63.5% at age 1 year, 58.6% at age 5 years, 54.6% at age 10 years, and 32.6% to age 15 years. The Kaplan-Meier survival estimates for cases of hypoplastic left ventricle co-occurring with additional CHD were 90.9% at age 1 week, 84.9% at 1 month, 73.7% at age 1 year, 67.7% to age 5 years, 59.2% to age 10 years, and 40.3% to age 15 years. Preterm birth (p = 0.007), low birth weight (p = 0.005), and female sex (p = 0.01) were associated with mortality. Conclusions: We have shown that prognosis associated with HLHS in the twenty first century exceeds that of many previous population-based studies, likely due to improvements in intensive care technologies and advances in surgical techniques over the last few decades.

Single Ventricle-A Comprehensive Review

In this paper, the author enumerates cardiac defects with a functionally single ventricle, summarizes single ventricle physiology, presents a summary of management strategies to address the single ventricle defects, goes over the steps of staged total cavo-pulmonary connection, cites the prevalence of inter-stage mortality, names the causes of inter-stage mortality, discusses strategies to address the inter-stage mortality, reviews post-Fontan issues, and introduces alternative approaches to Fontan circulation.

Common atrioventricular valve surgery in children with functional single ventricle

OBJECTIVES

A common atrioventricular valve (CAVV) is considered to be a risk factor for early and late deaths in patients with functional single ventricle (FSV). CAVV surgery in patients with FSV is challenging and there is limited knowledge of the outcomes of CAVV repair with univentricular physiology.

METHODS

We reviewed all CAVV surgical procedures in patients with FSV who underwent univentricular palliation. End points of the study were survival after CAVV surgery and cumulative incidence of reoperation.

RESULTS

Between 1984 and 2019, 66 children with CAVV and FSV underwent single-ventricle palliation, of whom 45.5% (30/66) required CAVV surgery. Indication for surgery was moderate CAVV regurgitation in 40% (12/30) and severe CAVV regurgitation in 60% (18/30). CAVV repair was performed in 93.3% (28/30) and CAVV replacement in 6.7% (2/30). The median age and weight at surgery were 0.9 years (interquartile range 0.3-1.8) and 6.5 kg (interquartile range 3.9-8.7), respectively. Operative and late mortality were 23.3% and 8.7%, respectively. Survival and cumulative incidence of reoperation at 4 years after CAVV surgery were 68.9% [standard deviation (SD): 8.7] and 35.8% (SD: 9.1), respectively. Fontan completion was achieved in 60% (18/30). Survival at 4 years after birth was 69.7% (SD: 8.5) in 30 patients with CAVV surgery, whereas it was 83% (SD: 6.3) in 36 patients without CAVV surgery (P = 0.32).

CONCLUSIONS

CAVV surgery in patients with FSV is associated with substantial mortality and a high incidence of reoperation.

Long-term outcomes of atrioventricular septal defect and single ventricle: A multicenter study

OBJECTIVE

The study objective was to analyze survival and incidence of Fontan completion of patients with single-ventricle and concomitant unbalanced atrioventricular septal defect.

METHODS

Data from 4 Dutch and 3 Belgian institutional databases were retrospectively collected. A total of 151 patients with single-ventricle atrioventricular septal defect were selected; 36 patients underwent an atrioventricular valve procedure (valve surgery group). End points were survival, incidence of Fontan completion, and freedom from atrioventricular valve reoperation.

RESULTS

Median follow-up was 13.4 years. Cumulative survival was 71.2%, 70%, and 68.5% at 10, 15, and 20 years, respectively. An atrioventricular valve procedure was not a risk factor for mortality. Patients with moderate-severe or severe atrioventricular valve regurgitation at echocardiographic follow-up had a significantly worse 15-year survival (58.3%) compared with patients with no or mild regurgitation (89.2%) and patients with moderate regurgitation (88.6%) (P = .033). Cumulative incidence of Fontan completion was 56.5%, 71%, and 77.6% at 5, 10, and 15 years, respectively. An atrioventricular valve procedure was not associated with the incidence of Fontan completion. In the valve surgery group, freedom from atrioventricular valve reoperation was 85.7% at 1 year and 52.6% at 5 years.

CONCLUSIONS

The long-term survival and incidence of Fontan completion in our study were better than previously described for patients with single-ventricle atrioventricular septal defect. A concomitant atrioventricular valve procedure did not increase the mortality rate or decrease the incidence of Fontan completion, whereas patients with moderate-severe or severe valve regurgitation at follow-up had a worse survival. Therefore, in patients with single-ventricle atrioventricular septal defect when atrioventricular valve regurgitation exceeds a moderate degree, the atrioventricular valve should be repaired.

Restriction of Atrial Septal Defect Leads to Growth of Hypoplastic Ventricle in Patients with Borderline Right or Left Heart

Patients with borderline hypoplastic right or left ventricle and VSD may be candidates for either single ventricle palliation or staged ventricular recruitment (SVR) followed by eventual biventricular conversion. Components of SVR include restriction of atrial septal defects (ASD) without ventricular septal defects (VSD) closure and addition of accessory pulmonary blood flow. This study evaluated the impact of ASD restriction on ventricular growth and function. We retrospectively reviewed patients with borderline ventricular hypoplasia and VSD who underwent a staged ventricular recruitment (SVR) procedure from 2012 to June 2019. Pre- and post-recruitment MRI and echocardiogram data were compared and analyzed. We excluded cases in which we intentionally restricted VSD with simultaneous ASD restriction. Forty-six patients (41 with right-dominant ventricle, 25 with risk factors for Fontan procedure) underwent SVR at a median age of 15.1 months' (interquartile range (IQR), 7.2-37.2 months'). The median indexed ventricular end-diastolic volume, end-systolic volume, and stroke volume according to cardiac MRI significantly increased at median 11.0 months' (IQR:7.8~14.1 months') after recruitment. Among them, except 2 operative mortalities after SVR, 26 patients underwent bi-ventricular repair (56.5% including one and a half ventricle repair) at a median of 8.0 months' (IQR: 6.2-12.2 months') after recruitment. Fifteen patients await biventricular completion, and 3 patients underwent single ventricle palliation. Pulmonary blood flow (Qp) tended to increase after recruitment regardless of type of pulmonary blood flow modification without statistical significance. Six patients died at a median duration of 6.5 months' (IQR: 2.9-11.7) after SVR; 3 patients died after biventricular completion, 2 after recruitment, and 1 after returning to single ventricle palliation. All of them were considered poor Fontan candidates due to severe atrioventricular valve regurgitation, pulmonary hypertension, pulmonary vein stenosis, or airway stenosis. Restriction of the atrial septum leads to the growth of hypoplastic ventricle in patients with ventricular septal defects who undergo SVR regardless of the preoperative characteristics, and eventual biventricular repair can be performed in a subgroup of these patients. Future work is necessary to optimize timing of SVR and method of accessory pulmonary blood flow.

Super Glenn for staged biventricular repair: impact on left ventricular growth?

 

OBJECTIVES

The Super Glenn procedure involves targeted increased in blood flow to left sided heart structures with fenestrated atrial septation. The objective of this study was to examine the outcomes of patients who had this procedure as a part of biventricular staging and specifically evaluate the effect on dimensions of left heart structures.

METHODS

Data for patients who had this procedure between 2005 and 2019 were retrospectively identified.

RESULTS

Thirty-seven patients were identified. Most common diagnosis was hypoplastic left heart syndrome in 40% (n = 15). On echocardiography, the median mitral valve z score was -2.26. On cardiac magnetic resonance imaging, median indexed left ventricular end-diastolic volume was 31.5 ml/m2 and mitral/tricuspid inflow ratio was 0.35. The median age at Super Glenn was 2.3 years (interquartile range 1.5-3.6) while median weight was 12 kg (interquartile range 9.8-14). There were no early/hospital deaths. The median intensive care unit length of stay was 4 days, and median hospital length of stay was 10 days. Median follow-up for the entire cohort was 3 years (range 15 days to 13.2 years). There was a statistically significant increase in indexed left ventricular dimensions. There were 5 deaths (14%). Three patients (8%) underwent heart transplant. Freedom from death/transplant was 79% at 5 years. Seven patients (19%) needed a reoperation. Twenty-three patients (62%) underwent biventricular conversion after a median of 11.3 months after Super Glenn.

CONCLUSIONS

The Super Glenn procedure achieves consistent increase in left ventricular dimensions. This may be a useful strategy to help achieve a successful biventricular circulation in patients with borderline left ventricle. The superiority/non-inferiority of this approach over the conventional Fontan pathway is unclear.

Can Left Atrioventricular Valve Reduction Index (LAVRI) Predict the Surgical Strategy for Repair of Atrioventricular Septal Defect?

Despite improved survival, surgical treatment of atrioventricular septal defect (AVSD) remains challenging. The optimal technique for primary left atrioventricular valve (LAVV) repair and prediction of suitability for biventricular approach in unbalanced AVSD are still controversial. We evaluated the ability of our recently developed echocardiographic left atrioventricular valve reduction index (LAVRI) in predicting LAVV reoperation rate and surgical strategy for unbalanced AVSD. Retrospective echocardiographic analysis was available in 352 of 790 patients with AVSD treated in our institution and included modified atrioventricular valve index (mAVVI), ventricular cavity ratio (VCR), and right ventricle/left ventricle (RV/LV) inflow angle. LAVRI estimates LAVV area after complete cleft closure and was analyzed with regard to surgical strategy in primary LAVV repair and unbalanced AVSD. Of the entire cohort, 284/352 (80.68%) patients underwent biventricular repair and 68/352 (19.31%) patients underwent univentricular palliation. LAVV reoperation was performed in 25/284 (8.80%) patients after surgical correction of AVSD. LAVRI was significantly lower in patients requiring LAVV reoperation (1.92 cm²/m² [IQR 1.31] vs. 2.89 cm²/m² [IQR 1.37], p = 0.002) and significantly differed between patients receiving complete and no/partial cleft closure (2.89 cm²/m² [IQR 1.35] vs. 2.07 cm²/m² [IQR 1.69]; p = 0.002). Of 82 patients diagnosed with unbalanced AVSD, 14 were suitable for biventricular repair (17.07%). mAVVI, LAVRI, VCR, and RV/LV inflow angle accurately distinguished between balanced and unbalanced AVSD and predicted surgical strategy (all p < 0.001). LAVRI may predict surgical strategy in primary LAVV repair, LAVV reoperation risk, and suitability for biventricular approach in unbalanced AVSD anatomy.

Effect of Earlier Atrioventricular Valve Intervention on Survival After the Fontan Operation

Whereas the prevalence and impact of atrioventricular valve (AVV) regurgitation in patients with single ventricle physiology has become increasingly apparent, the optimal timing for valve intervention is unclear. To investigate this, we performed a retrospective review of all 1,167 patients from the Mayo Clinic Fontan database. Thirteen percent (153 patients) had AVV repair or replacement during their staged single ventricle palliation. We found that patients with right ventricular morphology and common AVV were at increased risk for AVV intervention. Patients who underwent AVV intervention had increased risk of death/transplant compared with those who did not (hazards ratio [HR] = 1.75, 95% CI 1.37 to 2.23, p <0.001). With respect to valve intervention timing, whereas AVV intervention before Fontan presented similar risk for death/transplant compared with no AVV intervention (HR = 0.85, 95% CI 0.32 to 2.27, p = 0.74), intervention at time of Fontan had a significantly higher risk (HR = 1.46, 95% CI 1.09 to 1.97, p = 0.01), and intervention after Fontan had a much more substantial risk (HR = 3.83, 95% CI 2.54 to 5.79, p <0.001). AVV repair failure occurred in 11% of patients. In terms of relative risk of valve repair versus replacement, in post-Fontan AVV intervention patients, AVV replacement carried a 2.9 fold risk of death/transplant compared with AVV repair. In conclusion, AVV disease remains a considerable challenge for durable Fontan physiology. This data demonstrates that earlier intervention on valve pathology improves survival with the Fontan circulation. Continued surveillance of single ventricle patients and prompt referral of those with valve pathology can improve outcomes in this challenging population.

Single-ventricle palliation in children with atrioventricular septal defect and transposition of the great arteries: 45 years of experience

BACKGROUND

The association of atrioventricular septal defect and transposition of the great arteries is very rare. As a rule, these patients have unbalanced ventricles. However, there have been no studies describing the results of single-ventricle palliation in these children.

METHODS

All children who underwent surgery with a diagnosis of atrioventricular septal defect and transposition of the great arteries were included in the study. Data were obtained from medical records.

RESULTS

A total of 38 patients with atrioventricular septal defect and transposition of the great arteries underwent single-ventricle palliation at the study institution between 1971 and 2016. The mean follow-up was 12.4 years (median: 14.6 years, range 2-43.3 years). Most children had unbalanced atrioventricular septal defect (94.7%, 36/38). Survival was 67.6% (95% confidence interval [CI]: 50.0-80.2%) at 10 years and 57.8% (95% CI: 38.0-73.4%) at 20 years. By 10 years, 58.6% (95% CI: 40.8-72.7%) had progressed to Fontan completion, while 32.5% (95% CI: 18.2-47.6%) had died. In patients achieving Fontan completion, 20-year event-free survival was 73.3% (95% CI: 34.8-91.3%), while 5.0% (95% CI: 0.4-20.5%) had undergone cardiac transplantation and 21.7% (95% CI: 3.2-50.8%) had undergone takedown of the Fontan circulation. Freedom from atrioventricular valve surgery was 57.0% (95% CI: 37.2-72.7%) at 10 and 20 years.

CONCLUSIONS

The association of atrioventricular septal defect and transposition of the great arteries is very rare, and most of these children have unbalanced ventricles. Single-ventricle palliation results in 25-year overall survival of 50%. However, in patients, who had Fontan completion, survival was 75% at 25 years after Fontan operation.

Atrioventricular Valve Regurgitation in Single Ventricle Heart Disease: A Common Problem Associated With Progressive Deterioration and Mortality

The Fontan procedure has provided patients with single ventricle physiology extended survival into adulthood and in many cases has improved their quality of life. Atrioventricular valve regurgitation (AVVR) is common in single ventricle patients and is associated with increased risk of mortality. AVVR is more common in patients with a systemic tricuspid or common atrioventricular valve but is generally progressive irrespective of underlying valve morphology. AVVR can be attributable to diverse structural and functional abnormalities at multiple levels of the valvar apparatus, as well as ventricular dysfunction and dilation. Multiple imaging modalities including recent advances in 3‐dimensional echocardiography and cross‐sectional imaging have been used to further understand AVVR. Surgery to address AVVR must be tailored to the underlying mechanism and the timing of surgical repair should be chosen carefully. In this review, we discuss the etiologies, treatment options, surgical timing, and outcomes of valve repair or replacement for AVVR in patients with single ventricle congenital heart disease, with a focus on those with a Fontan circulation as AVVR is associated with increased risk for Fontan failure and mortality. In‐depth understanding of the current literature will help guide clinicians in their approach and management of AVVR in this population.

Percutaneous edge-to-edge repair for common atrioventricular valve regurgitation in a patient with heterotaxy syndrome, single ventricle physiology, and unbalanced atrioventricular septal defect

Congenital heart disease patients, specifically with unbalanced atrioventricular septal defects and common atrioventricular valves requiring single ventricle palliation, have substantial morbidity and mortality. Atrioventricular valve regurgitation (AVVR) is associated with poor outcomes in single ventricle patients, and many of them require surgical treatment of AVVR in their lifetimes. We describe a unique case of transcatheter edge-to-edge valve repair using the MitraClip system (Abbott, Chicago, IL) in a single ventricle patient with severe common AVVR.

Outcomes of Multistage Palliation of Infants With Single Ventricle and Atrioventricular Septal Defect

Background:

Published palliation outcomes of infants with functional single ventricle (SV) and common atrioventricular septal defect (AVSD) are poor due to associated cardiac and extracardiac anomalies and development of atrioventricular valve (AVV) regurgitation. We report current palliation results.

Methods:

From 2002 to 2012, 80 infants with functional SV with AVSD underwent multistage palliation. Competing-risks analyses modeled events after first-stage surgery and Glenn (death/transplantation vs next palliation surgery) and examined factors associated with survival and AVV intervention.

Results:

Sixty-eight (80%) patients received neonatal palliation: modified Blalock-Taussig shunt (n = 33, 41%), Norwood (n = 20, 25%), and pulmonary artery band (n = 15, 19%), whereas 12 (15%) received primary Glenn. On competing-risks analysis, one-year following first-stage surgery, 29% of patients had died or received transplantation and 62% had undergone Glenn. Five years following Glenn, 9% of patients had died or received transplantation and 68% had undergone Fontan. Overall eight-year survival was 64% and was lower in patients with genetic syndromes (53% vs 82%), patients requiring concomitant total anomalous pulmonary venous connection repair (53% vs 69%), and those requiring neonatal palliation (48% vs 100%). Factors associated with mortality were unplanned reoperation (hazard ratio [HR]: 3.7 [1.7-8.0], P = .001) and extracorporeal membrane oxygenation use (HR: 7.1 [3.0-16.6], P < .001). Initial AVV regurgitation ≥ moderate was associated with AVV intervention (HR: 6.2 [2.4-16.1], P = .002) with eight-year freedom from death or AVV intervention of 25% in those patients.

Conclusions:

Patients with SV with AVSD are a distinct group and commonly have associated cardiac and extracardiac malformations that complicate care and affect survival. The development of AVV regurgitation requiring intervention is common but does not affect survival.

Surgical palliation of univentricular heart disease in children with Down's syndrome: A systematic review

Objectives

No standard protocol is available for the management of children with Down's syndrome (DS) and a functional single ventricle. This review attempts to determine the outcomes of the single ventricular surgical palliation pathway in high-risk children with DS.

Methods

Several databases were searched using the following MeSH terms: ‘Congenital heart disease’, ‘Atrioventricular septal defect’, ‘Balanced AVSD’, ‘Unbalanced AVSD’, ‘Down's syndrome’, ‘Univentricular repair’, ‘bidirectional Glenn procedure’, and ‘Fontan procedure’. A structured algorithm was used for the selection of studies for an in-depth analysis.

Results

There was no universal agreement on the best surgical approach for unbalanced atrioventricular septal defect in DS. The majority of paediatric cardiac surgeons did not recommend the complete Fontan procedure; conversely, the use of a Glenn shunt (superior cavopulmonary connection) was preferred.

Conclusions

Careful assessment of the suitability for Fontan surgery, including the absence of elevated pulmonary vascular resistance, pulmonary arterial anatomy, and function of the dominant ventricle, is mandatory. A staged surgical procedure ending with complete Fontan repair provides acceptable medium-term results.

Trends in Long-Term Mortality After Congenital Heart Surgery

BACKGROUND

Congenital heart surgery has improved the survival of patients with even the most complex defects, but the long-term survival after these procedures has not been fully described.

OBJECTIVES

The purpose of this study was to evaluate the long-term survival of patients (age <21 years) who were operated on for congenital heart defects (CHDs).

METHODS

This study used the Pediatric Cardiac Care Consortium data, a U.S.-based, multicenter registry of pediatric cardiac surgery. Survival analysis included 35,998 patients who survived their first congenital heart surgery at <21 years of age and had adequate identifiers for linkage with the National Death Index through 2014. Survival was compared to that in the general population using standardized mortality ratios (SMRs).

RESULTS

After a median follow-up of 18 years (645,806 person-years), 3,191 deaths occurred with an overall SMR of 8.3 (95% confidence interval [CI]: 8.0 to 8.7). The 15-year SMR decreased from 12.7 (95% CI: 11.9 to 13.6) in the early era (1982 to 1992) to 10.0 (95% CI: 9.3 to 10.8) in the late era (1998 to 2003). The SMR remained elevated even for mild forms of CHD such as patent ductus arteriosus (SMR 4.5) and atrial septal defects (SMR 4.9). The largest decreases in SMR occurred for patients with transposition of great arteries (early: 11.0 vs. late: 3.8; p < 0.05), complete atrioventricular canal (31.3 vs. 15.3; p < 0.05), and single ventricle (53.7 vs. 31.3; p < 0.05).

CONCLUSIONS

In this large U.S. cohort, long-term mortality after congenital heart surgery was elevated across all forms of CHD. Survival has improved over time, particularly for severe defects with significant changes in their management strategy, but still lags behind the general population.

Outcomes of Common Atrioventricular Valve Repair in Patients With Single-Ventricle Physiology - Indication, Timing and Repair Techniques

BACKGROUND

Common atrioventricular valve (CAVV) repair in patients with a single ventricle remains a great challenge and a refractory issue for pediatric cardiac surgeons.

METHODS AND RESULTS

From January 2007 to April 2018, 37 consecutive patients with a single ventricle who underwent CAVV repair were included in the study group. Patients were divided into 2 groups based on the repair technique: patients in Group A were treated using the bivalvation technique, and patients in Group B underwent conventional repair techniques; baseline data were similar between groups. The inhospital and follow-up mortality were 5.4% (2/37) and 11.4% (4/35), respectively. After a follow-up of 65.5±29.3 months, the estimated 1-, 5-, and 10-year overall survival rates were 94.6%, 83.4%, and 77.0%, respectively. The rates of freedom from CAVV failure were 94.3%, 72.7%, and 62.9% after 1, 5, and 10 years, respectively. In the multivariate analysis, the independent factors for CAVV repair failure were repair technique (P=0.004) and heterotaxy syndrome (P=0.003). A total of 30 patients (81.1%) completed total cavopulmonary connection (TCPC); 3 patients required re-intervention; 24 of 31 patients (77.4%) were in New York Heart Association classes II and I at the latest follow-up.

CONCLUSIONS

Outcomes of CAVV repair in patients palliated by single-ventricular surgery are acceptable. The bivalvation technique is a simple and effective technique.

Partition of Common Atrioventricular Valve in a Patient With Dextrocardia and Univentricular Circulation

Long-term outcomes in children with atrioventricular septal defect (AVSD) and univentricular palliation are of concern, with <60% survival at 25 years.¹ Common atrioventricular valves (AVV) often become insufficient in patients with univentricular physiology, leading to heart failure.^1,2 We have recently observed that outcomes of children with AVSD who reach Fontan circulation are not as bad as previously thought, provided that the AVV remains competent.¹ Common AVV surgery is associated with substantial mortality and reoperation rates.³ Although successful AVV repair is associated with better survival and freedom from reoperation, good quality repair is difficult to achieve in univentricular circulation,³ especially in patients with dextrocardia.⁴ Herein, we report a patient with unbalanced AVSD and dextrocardia who underwent AVV repair using the "polytetrafluoroethylene (Gore-Tex, W.L. Gore & Associates, Flagstaff, AZ) bridge" technique⁵ with excellent early outcome.

Recent advances in managing septal defects: ventricular septal defects and atrioventricular septal defects

This review discusses the management of ventricular septal defects (VSDs) and atrioventricular septal defects (AVSDs). There are several types of VSDs: perimembranous, supracristal, atrioventricular septal, and muscular. The indications for closure are moderate to large VSDs with enlarged left atrium and left ventricle or elevated pulmonary artery pressure (or both) and a pulmonary-to-systemic flow ratio greater than 2:1. Surgical closure is recommended for large perimembranous VSDs, supracristal VSDs, and VSDs with aortic valve prolapse. Large muscular VSDs may be closed by percutaneous techniques. A large number of devices have been used in the past for VSD occlusion, but currently Amplatzer Muscular VSD Occluder is the only device approved by the US Food and Drug Administration for clinical use. A hybrid approach may be used for large muscular VSDs in small babies. Timely intervention to prevent pulmonary vascular obstructive disease (PVOD) is germane in the management of these babies. There are several types of AVSDs: partial, transitional, intermediate, and complete. Complete AVSDs are also classified as balanced and unbalanced. All intermediate and complete balanced AVSDs require surgical correction, and early repair is needed to prevent the onset of PVOD. Surgical correction with closure of atrial septal defect and VSD, along with repair and reconstruction of atrioventricular valves, is recommended. Palliative pulmonary artery banding may be considered in babies weighing less than 5 kg and those with significant co-morbidities. The management of unbalanced AVSDs is more complex, and staged single-ventricle palliation is the common management strategy. However, recent data suggest that achieving two-ventricle repair may be a better option in patients with suitable anatomy, particularly in patients in whom outcomes of single-ventricle palliation are less than optimal. The majority of treatment modes in the management of VSDs and AVSDs are safe and effective and prevent the development of PVOD and cardiac dysfunction.

Long-Term Outcome After Pulmonary Artery Banding in Children With Atrioventricular Septal Defects

BACKGROUND

Patients with atrioventricular septal defect (AVSD) may require pulmonary artery banding (PAB), either as a part of a staged univentricular palliation or to allow delayed biventricular repair in patients presenting with early heart failure. The long-term outcomes of PAB in children with AVSD have not been previously reported.

METHODS

All children with AVSD who underwent PAB at a single institution were included in the study. Data were obtained from medical records and correspondence with general practitioners and cardiologists.

RESULTS

A total of 68 patients with complete AVSD underwent PAB, of whom 58.8% of patients (40 of 68) had balanced AVSD (bAVSD) and underwent PAB with intent to subsequently perform biventricular repair. The remaining 41.2% of patients (28 of 68) had unbalanced AVSD (uAVSD) and underwent PAB as part of staged univentricular repair. PAB was not associated with a short-term increase in atrioventricular valve (AVV) regurgitation (p = 0.24). In patients with bAVSD, 83.8% (95% confidence interval [CI]: 67.4% to 92.4%) achieved biventricular repair. Survival was 73.4% (95% CI: 54.3% to 85.5%) and freedom from left AVV operation was 60.0% (95% CI: 36.1% to 77.4%) at 20 years of follow-up. In patients with uAVSD, 61.9% (95% CI: 40.5% to 77.5%) had achieved Fontan completion at 10 years of follow-up. Survival was 60.9% (95% CI: 36.2% to 78.5%) and freedom from AVV operation was 78.6% (95% CI: 55.5% to 90.6%) at 20 years.

CONCLUSIONS

PAB can be used in patients with AVSD without compromising AVV function. Most patients with bAVSD progress to biventricular repair, albeit with a high rate of AVV reoperation. Patients with uAVSD who undergo PAB have similar outcomes to the overall uAVSD population.

Common atrioventricular valve failure during single ventricle palliation†

OBJECTIVES

To determine the risk of atrioventricular valve failure (valve intervention or moderate or greater regurgitation) during the lifetime of patients with single ventricle physiology and common atrioventricular valve.

METHODS

Patients' data were extracted from an existing bi-national, population based registry. A retrospective review of their medical records was undertaken to determine the incidence of atrioventricular valve repair/replacement or moderate or greater regurgitation.

RESULTS

From a registry of 1468 Fontan survivors, 136 patients with common atrioventricular valve were identified. Complete echocardiographic follow-up was available for 114 patients. Median length of follow-up was 10.2 years (interquartile range 5-15 years). Twenty-five year survival and freedom from Fontan failure were 94% [95% confidence interval (CI), 88-100%] and 74% (95% CI, 64-87%), respectively. Twenty-eight patients underwent 24 initial repairs and 4 replacements. The 24 patients undergoing repair subsequently needed 6 re-repairs, 2 replacements and 8 had moderate or greater regurgitation at last follow-up. Four-year freedom from atrioventricular valve repair failure was 50% (95% CI, 34-75%). An additional 30 patients developed moderate or greater atrioventricular valve regurgitation (6 New York Heart Association ≥3, 10 Fontan failures, 0 deaths). Cumulative incidence of the composite endpoint of atrioventricular valve failure at 28 years was 62% (95% CI, 49-74%).

CONCLUSIONS

Patients with single ventricle physiology and common atrioventricular valve experience a continuous decline in valve function. The majority of patients experience valve failure in the first 30 years of life.