Determinants of mortality and type of repair in neonates with pulmonary atresia and intact ventricular septum

Comparison of Ductal Stent Versus Surgical Shunt as Initial Intervention for Neonates with Pulmonary Atresia with Intact Ventricular Septum

Data comparing surgical systemic-to-pulmonary artery shunt and patent ductus arteriosus (PDA) stent as the initial palliation procedure for patients with pulmonary atresia with intact ventricular septum (PA-IVS) are limited. We sought to compare characteristics and outcomes in a multicenter cohort of patients with PA-IVS undergoing surgical shunts versus PDA stents. We retrospectively reviewed neonates with PA-IVS from 2009 to 2019 in 19 United States centers. Bivariate comparisons and multivariable logistic regression analysis were performed to determine the relationship between initial palliation strategy and outcomes including major adverse cardiovascular events (MACE): stroke, mechanical circulatory support, cardiac arrest, or death. 187 patients were included: 38 PDA stents and 149 surgical shunts. Baseline characteristics did not differ statistically between groups. Post-procedural MACE occurred in 4 patients (11%) with PDA stents versus 38 (26%) with surgical shunts, p = 0.079. Overall, the initial palliation strategy was not significantly associated with MACE (aOR:0.37; 95% CI,0.13-1.02). In patients with moderate-to-severe right ventricle hypoplasia, PDA stents were significantly associated with decreased odds of MACE (aOR:0.36; 95% CI,0.13-0.99). PDA stents were associated with lower vasoactive inotrope scores (median 0 versus 5, p < 0.001), greater likelihood to be extubated at the end of their procedure (37% versus 4%, p < 0.001), and shorter duration of mechanical ventilation (median 24 versus 96 h, p < 0.001). PDA stents were associated with significantly more unplanned reinterventions for hypoxemia compared to surgical shunts (42% vs. 20%, p = 0.009). In this multicenter study, neonates with PA-IVS who underwent PDA stenting received less vasoactive and ventilatory support postoperatively compared to those who had surgical shunts. Furthermore, patients with the most severe morphology had decreased odds of MACE.

Borderline Ventricles: From Evaluation to Treatment

A heart with a borderline ventricle refers to a situation where there is uncertainty about whether the left or right underdeveloped ventricle can effectively support the systemic or pulmonary circulation with appropriate filling pressures and sufficient physiological reserve. Pediatric cardiologists often deal with congenital heart diseases (CHDs) associated with various degrees of hypoplasia of the left or right ventricles. To date, no specific guidelines exist, and surgical management may be extremely variable in different centers and sometimes even in the same center at different times. Thus, the choice between the single-ventricle or biventricular approach is always controversial. The aim of this review is to better define when "small is too small and large is large enough" in order to help clinicians make the decision that could potentially affect the patient's entire life.

Surgical outcomes of the systemic-to-pulmonary artery shunt: risk factors of post-operative acute events and effectiveness of regulation of pulmonary blood flow with metal clips

OBJECTIVES

The aim of this study was to analyze the risk factors for acute events after systemic-to-pulmonary shunt (SPS) and to investigate the effectiveness of pulmonary blood flow regulation with a metal clip.

METHODS

The case histories of 116 patients (78 biventricular [BV] and 38 single ventricle [SV] physiology) who underwent SPS between 2010 and 2021 were retrospectively reviewed. Our strategy was to delay SPS until 1 month of age; pulmonary blood flow (PBF) regulation by partial clipping of the graft, if needed. Cases of aortic cross-clamping were excluded from this study.

RESULTS

CPB was used in 49 (42%) patients: the median age at SPS was 1 month (2 days to 16 years), and the sternotomy approach in 65. Discharge survival was 98.3% (114/116); hospital death occurred in 1.7% due to coronary ischemia. Inter-stage mortality occurred in 1.7% (shunt thrombosis, 1; pneumonia, 1). Pre-discharge acute events occurred in 7 patients (6.0%): thrombosis 3, pulmonary over-circulation 2, and coronary ischemia 2. Multiple logistic regression analysis revealed that pulmonary atresia with intact ventricular septum (PA/IVS) (p = 0.0253) was an independent risk factor for acute events. Partial clipping of the graft was performed in 24 patients (pulmonary atresia 15) and clip removal was performed by catheter intervention in 9 patients; no coronary ischemic events and graft injury occurred in these patients.

CONCLUSION

Surgical outcomes after SPS were acceptable and metal clip regulation of pulmonary blood flow appears to be safe and effective. PA/IVS was still a significant risk factor for acute events.

Pulmonary Atresia with Intact Ventricular Septum: Midterm Outcomes from a Multicenter Cohort

Contemporary multicenter data regarding midterm outcomes for neonates with pulmonary atresia with intact ventricular septum are lacking. We sought to describe outcomes in a contemporary multicenter cohort, determine factors associated with end-states, and evaluate the effect of right ventricular coronary dependency and coronary atresia on transplant-free survival. Neonates treated during 2009-2019 in 19 United States centers were reviewed. Competing risks analysis was performed to determine cumulative risk of each end-state, and multivariable regression analyses were performed to identify factors associated with each end-state and transplant-free survival. We reviewed 295 patients. Median tricuspid valve Z-score was - 3.06 (25%, 75%: - 4.00, - 1.52). Final end-state was biventricular repair for 45 patients (15.2%), one-and-a half ventricle for 16 (5.4%), Fontan for 75 (25.4%), cardiac transplantation for 29 (9.8%), and death for 54 (18.3%). Seventy-six patients (25.7%) remained in mixed circulation. Cumulative risk estimate of death was 10.9%, 16.1%, 16.9%, and 18.8% at 1, 6 months, 1 year, and 5 years, respectively. Tricuspid valve Z-score was inversely, and coronary atresia positively associated with death or transplantation [odds ratio (OR) = 0.46, (95% confidence interval (CI) = 0.29-0.75, p < 0.001) and OR = 3.75 (95% CI 1.46-9.61, p = 0.011), respectively]. Right ventricular coronary dependency and left coronary atresia had a significant effect on transplant-free survival (log-rank p < 0.001). In a contemporary multicenter cohort of patients with PAIVS, consisting predominantly of patients with moderate-to-severe right ventricular hypoplasia, we observed favorable survival outcomes. Right ventricular coronary dependency and left, but not right, coronary atresia significantly worsens transplant-free survival.

Current status of transcatheter intervention for complex right ventricular outflow tract abnormalities

Various transcatheter interventions for the right ventricular outflow tract (RVOT) have been introduced and developed in recent decades. Transcatheter pulmonary valve perforation was first introduced in the 1990s. Radiofrequency wire perforation has been the approach of choice for membranous pulmonary atresia in newborns, with high success rates, although complication rates remain relatively common. Stenting of the RVOT is a novel palliative treatment that may improve hemodynamics in neonatal patients with reduced pulmonary blood flow and RVOT obstruction. Whether this option is superior to other surgical palliative strategies or early primary repair of tetralogy of Fallot remains unclear. Transcatheter pulmonary valve replacement has been one of the biggest innovations in the last two decades. With the success of the Melody and SAPIEN valves, this technique has evolved into the gold standard therapy for RVOT abnormalities with excellent procedural safety and efficacy. Challenges remain in managing the wide heterogeneity of postoperative lesions seen in RVOT, and various technical modifications, such as pre-stenting, valve ring modification, or development of self-expanding systems, have been made. Recent large studies have revealed outcomes comparable to those of surgery, with less morbidity. Further experience and multicenter studies and registries to compare the outcomes of various strategies are necessary, with the ultimate goal of a single-step, minimally invasive approach offering the best longer-term anatomical and physiological results.

The Academic Impact of Congenital Heart Surgeons' Society (CHSS) Studies

PURPOSE

We reviewed all 64 articles ever published by The Congenital Heart Surgeons' Society (CHSS) Data Center to estimate the academic impact of these peer-reviewed articles.

MATERIALS AND METHODS

The Congenital Heart Surgeons' Society has performed research based on 12 Diagnostic Inception Cohorts. The first cohort (Transposition) began enrolling patients on January 1, 1985. We queried PubMed to determine the number of publications that referenced each of the 64 journal articles generated by the datasets of the 12 Diagnostic Inception Cohorts that comprise the CHSS Database. Descriptive summaries of the data were tabulated using mean with standard deviation and median with range.

RESULTS

Sixty-four peer-reviewed papers have been published based on the CHSS Database. Fifty-nine peer-reviewed articles have been published based on the 12 Diagnostic Inception Cohorts, and five additional articles have been published based on Data Science. Excluding the recently established Diagnostic Inception Cohort for patients with Ebstein malformation of tricuspid valve, the number of papers published per cohort ranged from 1 for coarctation to 11 for transposition of the great arteries. The 11 articles generated from the CHSS Transposition Cohort were referenced by a total of 111 articles (median number of references per journal article = 9 [range = 0-22, mean = 10.1]). Overall, individual articles were cited by an average of 11 (mean), and a maximum of 41 PubMed-listed publications. Overall, these 64 peer-reviewed articles based on the CHSS Database were cited 692 times in PubMed-listed publications. The first CHSS peer-reviewed article was published in 1987, and during the 35 years from 1987 to 2022, inclusive, the annual number of CHSS publications has ranged from 0 to 7, with a mean of 1.8 publications per year (median = 1, mode = 1).

CONCLUSION

Congenital Heart Surgeons' Society studies are widely referenced in the pediatric cardiac surgical literature, with over 10 citations per published article. These cohorts provide unique information unavailable in other sources of data. A tool to access this analysis is available at: [https://data-center.chss.org/multimedia/files/2022/CAI.pdf].

The Congenital Heart Surgeons' Society Kirklin/Ashburn Fellowship: The Fellows' Perspective

Since its establishment in 2001, the Congenital Heart Surgeons' Society John W. Kirklin/David Ashburn Fellowship has contributed substantially to the field of congenital heart surgery research while simultaneously training the next generation of surgeon- scientists. To date, ten fellows (and counting) have successfully completed this rigorous training, producing over 40 published articles focused on longitudinal outcomes from the various Congenital Heart Surgeons' Society cohorts. As the Kirklin/Ashburn Fellowship expands and additional fellows matriculate, its legacy, the network of support, and the contribution to congenital heart surgery research will undoubtedly hold strong.

Prediction of postnatal circulation in pulmonary atresia/critical stenosis with intact ventricular septum: systematic review and external validation of models

OBJECTIVE

A favorable postnatal prognosis in cases of pulmonary atresia/critical stenosis with intact ventricular septum (PA/CS-IVS) is generally equated with the possibility of achieving biventricular (BV) repair. Identification of fetuses that will have postnatal univentricular (UV) circulation is key for prenatal counseling, optimization of perinatal care and decision-making regarding fetal therapy. We aimed to evaluate the accuracy of published models for predicting postnatal circulation in PA/CS-IVS using a large internationally derived validation cohort.

METHODS

This was a systematic review of published uni- and multiparametric models for the prediction of postnatal circulation based on echocardiographic findings at between 20 and 28 weeks of gestation. Models were externally validated using data from the International Fetal Cardiac Intervention Registry. Sensitivity, specificity, predictive values, area under the receiver-operating-characteristics curves (AUCs) and proportion of cases with true vs predicted outcome were calculated.

RESULTS

Eleven published studies that reported prognostic parameters of postnatal circulation were identified. Models varied widely in terms of the main outcome (UV (n = 3), non-BV (n = 3), BV (n = 3), right-ventricle-dependent coronary circulation (n = 1) or tricuspid valve size at birth (n = 1)) and in terms of the included predictors (single parameters only (n = 6), multiparametric score (n = 4) or both (n = 1)), and were developed on small sample sizes (range, 15-38). Nine models were validated externally given the availability of the required parameters in the validation cohort. Tricuspid valve diameter Z-score, tricuspid regurgitation, ratios between right and left cardiac structures and the presence of ventriculocoronary connections (VCC) were the most commonly evaluated parameters. Multiparametric models including up to four variables (ratios between right and left structures, right ventricular inflow duration, presence of VCC and tricuspid regurgitation) had the best performance (AUC, 0.80-0.89). Overall, the risk of UV outcome was underestimated and that of BV outcome was overestimated by most models.

CONCLUSIONS

Current prenatal models for the prediction of postnatal outcome in PA/CS-IVS are heterogeneous. Multiparametric models for predicting UV and non-BV circulation perform well in identifying BV patients but have low sensitivity, underestimating the rate of fetuses that will ultimately have UV circulation. Until better discrimination can be achieved, fetal interventions may need to be limited to only those cases in which non-BV postnatal circulation is certain. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Transcatheter atrial septal defect closure late after completion of biventricular circulation in patients with pulmonary atresia intact ventricular septum or critical pulmonary stenosis

OBJECTIVE

This study aimed to explore anatomical and hemodynamic features of atrial septal defect, which was treated by transcatheter device closure late after completion of biventricular circulation in patients with pulmonary atresia and intact ventricular septum (PAIVS) or critical pulmonary stenosis (CPS).

METHODS

We studied echocardiographic and cardiac catheterization data, including defect size, retroaortic rim length, single or multiple defects, the presence of malalignment atrial septum, tricuspid and pulmonary valve diameters, and cardiac chamber sizes, in patients with PAIVS/CPS who underwent transcatheter closure of atrial septal defect (TCASD), and compared to control subjects.

RESULTS

A total of 173 patients with atrial septal defect, including 8 patients with PAIVS/CPS, underwent TCASD. Age and weight at TCASD were 17.3 ± 18.3 years and 36.6 ± 13.9 kg, respectively. There was no significant difference in defect size (13.7 ± 4.0 vs. 15.6 ± 5.2 mm, p = 0.317) and the retro-aortic rim length (3.7 ± 4.3 vs. 3.6 ± 0.3.1 mm, p = 0.948) between the groups; however, multiple defects (50% vs. 5%, p < 0.001) and malalignment atrial septum (62% vs. 14%. p < 0.001) were significantly frequent in patients with PAIVS/CPS compared to control subjects. The ratio of pulmonary to systemic blood flow in patients with PAIVS/CPS was significantly lower than that in the control patients (1.2 ± 0.4 vs. 2.0 ± 0.7, p < 0.001); however, four out of eight patients with atrial septal defect associated with PAIVS/CPS had right-to-left shunt through a defect, who were evaluated by the balloon occlusion test before TCASD. The indexed right atrial and ventricular areas, the right ventricular systolic pressure, and mean pulmonary arterial pressure did not differ between the groups. After TCASD, the right ventricular end-diastolic area remained unchanged in patients with PAIVS/CPS, whereas it significantly decreased in control subjects.

CONCLUSIONS

Atrial septal defect associated with PAIVS/CPS had more complex anatomy, which would be a risk for device closure. Hemodynamics should be individually evaluated to determine the indication for TCASD because PAIVS/CPS encompassed anatomical heterogeneity of the entire right heart.

Outcomes of infants with pulmonary atresia with intact ventricular septum listed for heart transplantation: A multi-institutional study

BACKGROUND

Management of infants with pulmonary atresia/intact ventricular septum (PA/IVS) is variable. Because of higher mortality in more severe forms, heart transplant (HT) is an acceptable approach, but waitlist and post-transplant outcomes are unclear. This study compared outcomes of infants with PA/IVS vs. other single ventricle (SV) anatomies listed for HT.

METHODS

Data from the Pediatric Heart Transplant Society (1993-2018) were analyzed for survival and risk factors for mortality.

RESULTS

Of 1617 SV infants, 300 had PA/IVS (19%) and 1317 had other SV (81%). Overall, 1-, 5-, and 10-year survival was higher among PA/IVS (74%, 65%, 61%) versus other SV infants (62%, 54%, 50%, p = .004). While waitlist mortality was similar between groups (p = .09), PA/IVS was an independent predictor of improved waitlist survival (HR 0.68, p = .03), and PA/IVS infants had higher incidence of waitlist removal (8% vs. 5.5%, p = .03), most commonly for being "too well." Post-transplant survival was superior among PA/IVS versus other SV infants (1- and 5-year survival 93% and 81% vs. 80% and 71%, p < .0001). Risk factors for PA/IVS waitlist mortality (2008-2018) included extracorporeal membrane oxygenation and mechanical ventilation. Prior aortopulmonary (AP) shunt among PA/IVS infants was associated with improved waitlist survival.

CONCLUSIONS

Overall survival among PA/IVS infants listed for HT exceeds that of other SV infants with PA/IVS identified as an independent predictor of improved waitlist and post-transplant survival. Prior AP shunt among listed PA/IVS infants was associated with improved waitlist outcomes, though, which may reflect a listing selection bias.

Computed Tomographic Angiography Provides Reliable Coronary Artery Evaluation in Infants With Pulmonary Atresia Intact Ventricular Septum

Evaluate the use of coronary CTA as an initial assessment for determining Right Ventricle Dependent Coronary Circulation (RVDCC) in neonates with Pulmonary Atresia with Intact Ventricular Septum (PA IVS). Retrospective review of cases with coronary CTA and compare with available catheter angiography, pathology, surgical reports, and outcomes from Mar 2015 to May 2022. In our cohort of 16 patients, 3 were positive for RVDCC, confirmed by pathologic evaluation, and there was concordance for presence or absence of RVDCC with catheter angiography in 5 patients (4 negatives for RVDCC, 1 positive). Clinical follow up for the 8 patients that underwent RV decompression had no clinical evidence of myocardial ischemia. Our findings suggest that coronary CTA is reliable as first-line imaging for determination of RVDCC in neonates with PA IVS. These findings, if supported by further prospective study, may reserve invasive coronary angiography for cases with diagnostic uncertainty or at the time of necessary transcatheter interventions.

Procedural Outcomes of Pulmonary Atresia Intact Ventricular Septum in Neonates: A Multicenter Study

BACKGROUND

Multicenter contemporary data describing short-term outcomes following initial interventions of neonates with pulmonary atresia intact ventricular septum (PA-IVS) are limited. This multicenter study aims to describe characteristics and outcomes of PA-IVS neonates following their initial catheter or surgical intervention and identify factors associated with major adverse cardiac events (MACE).

METHODS

Neonates with PA-IVS who underwent surgical or catheter intervention between 2009-2019 in 19 centers were reviewed. Risk factors for MACE, defined as cardiopulmonary resuscitation, mechanical circulatory support, stroke, or in-hospital mortality, were analyzed using multivariable logistic regression model.

RESULTS

We reviewed 279 neonates: 79 (28%) underwent right ventricular decompression, 151 (54%) underwent systemic-to-pulmonary shunt or ductal stent placement only, 36 (13%) underwent right ventricular decompression with shunt or ductal stent placement, and 11 (4%) underwent transplantation. MACE occurred in 57 patients (20%): 26 (9%) received mechanical circulatory support, 37 (13%) received cardiopulmonary resuscitation, 16 (6%) suffered stroke, 23 (8%) died. The presence of two major coronary artery stenoses (adjusted OR: 4.99; 95% CI: 1.16-21.39) and lower weight at first intervention (adjusted OR: 1.52, 95% CI: 1.01-2.27) were significantly associated with MACE. Coronary ischemia was the most frequent presumed mechanism of death (n=10).

CONCLUSIONS

In a multicenter cohort, one in five neonates with PA-IVS experienced MACE following their initial intervention. Patients with two major coronary artery stenoses or lower weight at time of initial procedure were most likely to experience MACE and warrant vigilance during pre-intervention planning and post-intervention management.

Right ventricular outflow tract anomalies: Neonatal interventions and outcomes

Right ventricular outflow tract (RVOT) anomalies comprise a wide spectrum of congenital heart disease, typically characterized by obstruction to flow from the right ventricle to pulmonary arteries. This review highlights important considerations surrounding management strategy as well as clinical outcomes for the neonate with RVOT anomaly, including: pulmonary atresia with intact ventricular septum, congenital pulmonary valve stenosis, tetralogy of Fallot, and Ebstein anomaly with anatomic or physiologic RVOT obstruction.

Combined Norwood and cavopulmonary shunt as the first palliation in late presenters with hypoplastic left heart syndrome and single-ventricle lesions

OBJECTIVE

A primary cavopulmonary shunt as a component of the initial Norwood palliation could be an option in patients with hypoplastic left heart syndrome and single-ventricle lesions. We present our initial experience with this approach in carefully selected patients with unrestricted pulmonary blood flow and low pulmonary vascular resistance.

METHODS

The study included 16 patients; the mean age was 137.9 ± 84.2 days. All patients underwent a Norwood palliation consisting of atrial septectomy, Damus-Kaye-Stansel connection, and arch augmentation in addition to the cavopulmonary shunt as the initial palliation.

RESULTS

The mean preoperative pulmonary to systemic blood flow (Qp/Qs) ratio on room air (n = 9) and with 100% oxygen (n = 8) was 5.3 ± 3.2 and 8.6 ± 4.3, respectively. The mean pulmonary vascular resistance on room air (n = 10) and 100% oxygen (n = 9) was 4.8 ± 3.1 and 1.7 ± 0.97 WU/m², respectively. Delayed chest closure was needed in 12 patients, and 6 patients required postoperative inhaled nitric oxide. One patient underwent takedown of the cavopulmonary shunt and construction of the right ventricle to pulmonary artery conduit after 1 month. The mean intensive care unit stay was 18.9 ± 15.4 days. There were 2 in-hospital deaths (48 hours and 8 days after surgery) and 2 postdischarge deaths (6 months and 2 years after hospital discharge). Seven patients have undergone the Fontan completion successfully, and 5 patients await further surgery.

CONCLUSIONS

First-stage Norwood palliation with cavopulmonary shunt for patients with hypoplastic left heart syndrome or single-ventricle lesions is feasible in late presenters with low pulmonary vascular resistance.

Long-Term Outcomes After an Individualized Strategy in Patients with Pulmonary Atresia and Intact Ventricular Septum

This retrospective cohort study aimed to explore the long-term outcomes of an individualized strategy in patients with pulmonary atresia and intact ventricular septum (PAIVS). We analyzed survival and reintervention rates and identified risk factors for outcomes in patients with PAIVS treated based on individual right heart structures between 1979 and 2019. Ninety-five patients were included in this study. The z-scores of the pulmonary annulus, tricuspid annulus, and right ventricular end-diastolic volume were - 3.30 (- 15.15 to 1.83), - 0.70 (- 4.65 to 2.33), and - 1.51 (- 6.35 to 1.18), respectively. Right ventricular-dependent coronary circulation occurred in 15% of the patients. Among the 63 patients attempting biventricular strategy at first, 55 patients achieved biventricular circulation, 3 patients had one-and-a-half circulation, and 4 patients died perioperatively. Among the 33 patients attempting univentricular strategy at first, 10 patients died before the completion of Fontan operation, 17 patients (48%) accomplished Fontan operation, and 5 patients waited for Fontan operation. In one patient, conversion to biventricular circulation occurred. During the follow-up period of 720 person-years, the 20-year survival rate was significantly higher in patients with biventricular circulation than in those patients with univentricular circulation (93% vs. 67%, P < 0.001). Freedom from reintervention rates at 20 years was significantly lower in patients with biventricular circulation than in those patients with univentricular circulation (29% vs. 72%, P < 0.001). The pulmonary annulus z-score was an independent risk factor for reintervention in patients with biventricular circulation. Patients with biventricular circulation had an acceptable survival rate, but a high reintervention rate. Meanwhile, patients with univentricular circulation had high mortality before the completion of Fontan operation, although the reintervention rate was relatively low.

Systemic Venous Hypertension and Low Output Are Prevalent at Catheterization in Adults with Pulmonary Atresia and Intact Ventricular Septum Regardless of Repair Strategy

Patients with pulmonary atresia and intact ventricular septum (PA-IVS) require intervention early in life, and most survive to a definitive procedure of either Fontan circulation or right ventricle to pulmonary artery (RV-PA) repair. It remains unknown how surgical strategy impacts hemodynamics and comorbidities in adults. Retrospective analysis of adults (age ≥18 years) with PA-IVS undergoing hemodynamic catheterization at Mayo Clinic, MN between January 2000 through January 2020 was performed. 14 patients in the RV-PA group (71% biventricular, 29% 1.5 ventricle repair) and 19 post-Fontan patients [9 lateral tunnel (48%), 6 atriopulmonary (32%), and 4 extracardiac (21%)] were identified. Median age was 29 (21, 34) years. There were no differences in demographics and laboratory data (including MELD-XI) between groups. All patients assessed for liver disease had evidence of hepatic congestion or cirrhosis (14 in the Fontan group and 4 in the RV-PA group). Invasive hemodynamics were comparable between groups with the Fontan and RV-PA groups having similar systemic venous pressure (15.7±4.4 vs. 14.3±6.2, p = .44) and cardiac output (2.2±0.6 vs. 2.0±0.4 L/min/m², p = .23). There was no difference in transplant-free survival (p = .92; 5-year transplant-free survival RV-PA 84%, Fontan 80%). Hemodynamic derangements, namely elevated systemic venous pressure and low cardiac output, are prevalent in patients with PA-IVS undergoing cardiac catheterization regardless of surgical strategy.

Increasing Use of Neonatal Catheter Intervention for Pulmonary Atresia With Intact Ventricular Septum: Management Trends From a Single Centre

BACKGROUND

There is increasing use of catheter-based therapy as part of the neonatal treatment algorithm for pulmonary atresia with an intact ventricular septum (PAIVS). The management strategies utilised and outcomes of patients with PAIVS at our centre have not been examined.

METHODS

A retrospective case series was undertaken including all infants with PAIVS born January 2009 to July 2019 (follow-up to January 2020) managed at The Children's Hospital at Westmead, New South Wales. Demographic features, anatomical substrate, management pathway and subsequent clinical outcomes were examined.

RESULTS

Fifty-two (52) infants were included (male n=28, 53.8%). The right ventricular morphology was classified as normal, mildly, moderately and severely hypoplastic in 3 (5.8%), 13 (25.0%), 19 (36.5%) and 17 (32.7%) patients respectively. Thirty-seven (37) patients underwent an initial aortopulmonary (AP) shunt (surgical shunt or patent ductus arteriosus [PDA] stent). The remaining 15 patients underwent an initial intervention to decompress the right ventricle. Twenty (20) patients underwent a neonatal catheter-based intervention. An initial catheter-based intervention was more likely in the second half of the period. Sixteen (16) patients had an attempted pulmonary valve perforation, 12 as their initial procedure. Median follow-up was 62 months (range 3-119 months). Final circulation status was known in 37 patients; biventricular n=14 (37.8%), "1.5 ventricles" n=4 (10.8%), single n=19 (51.4%). There were five deaths during the period (9.6%), including two during the initial procedural admission attributed to tamponade requiring extracorporeal membrane oxygenation (ECMO) at the time of percutaneous pulmonary valve perforation.

CONCLUSION

There has been an overall trend towards including catheter-based strategies in the neonatal period as part of management at our centre. Given the risk of bleeding and ECMO related to this, consideration should be given to the availability of multidisciplinary support when planning the timing of these procedures.

Infants with pulmonary atresia intact ventricular septum who require balloon atrial septostomy have significantly higher 18-month mortality

INTRODUCTION

Many newborns with pulmonary atresia/intact ventricular septum require intervention to establish pulmonary flow and sufficient cardiac output. The resulting haemodynamic changes are not well characterised and may have unintended consequences.

METHODS

This is a 30-year (1988-2018) retrospective study of patients with pulmonary atresia intact ventricular septum.

RESULTS

Eighty-nine patients were included, and median follow-up was 8 years. Fifty-five per cent had coronary sinusoids and 27% had right ventricular-dependent coronary circulation. Most patients were managed with surgical aortopulmonary or modified Blalock-Taussig shunt (73%), and 12 patients underwent balloon atrial septostomy before surgical intervention. The remaining patients (27%) underwent only transcatheter interventions; 7 required an atrial septostomy and 17 required ductal stentings. All-cause mortality was 10%, most deaths (89%) occurred before 18 months of age. Of these early deaths, 87% required a balloon atrial septostomy and 85% had right ventricular-dependent coronary sinusoids. Eighteen-month mortality was significantly higher for patients who required a balloon atrial septostomy compared to those who did not (36% versus 1.4% p < 0.0001).

DISCUSSION

Patients with pulmonary atresia/intact ventricular septum who require balloon atrial septostomy in the newborn period have significantly higher 18-month mortality. Quantifying the mortality difference may help guide prognostication and expectation setting. Infants who had septostomy and a surgical shunt in the newborn period fared better than those who only underwent septostomy (even when accompanied by ductal stenting). For infants with right ventricular-dependent circulation, atrial septostomy should only be performed on an urgent or emergent basis and these patients should be considered for early surgical intervention and neonatal transplant.

Survival With Respect to Morphology in Pulmonary Atresia and Intact Ventricular Septum in Sweden

BACKGROUND

Patients born with pulmonary atresia and intact ventricular septum represent a challenge to pediatric cardiologists. Our objective was to study changes in survival with respect to morphology in all children born with pulmonary atresia and intact ventricular septum in Sweden during 36 years.

METHODS

A retrospective, descriptive study based on medical reports and echocardiographic examinations consisting of those born between 1980 and 1998 (early group) and those born between 1999 and 2016 (late group).

RESULTS

The cohort consists of 171 patients (early group, n = 86 and late group, n = 85) yielding an incidence of 4.35 and 4.46 per 100,000 live births, respectively. One-year survival in the early group was 76% compared to 92% in the late group (P = .0004). For patients with membranous atresia, one-year survival increased from 78% to 98%, and for muscular pulmonary atresia, from 68% to 85%. In patients with muscular pulmonary atresia and ventriculocoronary arterial communications, there was no significant increase in survival. Risk factors for death were being born in the early time period hazard ratio (HR), 6; 95% CI (2.33-14.28) P = .0002, low birth weight HR, 1.26; 95% CI (1.14-1.4) P < .0001 and having muscular pulmonary atresia HR, 3.74; 95% CI (1.71-8.19) P = .0010.

CONCLUSION

The incidence of pulmonary atresia and intact ventricular septum remained unchanged during the study period. Survival has improved, especially for patients with membranous pulmonary atresia, while being born with muscular pulmonary atresia is still a risk factor for death. To further improve survival, greater focus on patients with muscular pulmonary atresia and ventriculocoronary arterial communications is required.

Utility of Fetal Cardiovascular Magnetic Resonance for Prenatal Diagnosis of Complex Congenital Heart Defects

Importance

Prenatal diagnosis of complex congenital heart defects reduces mortality and morbidity in affected infants. However, fetal echocardiography can be limited by poor acoustic windows, and there is a need for improved diagnostic methods.

Objective

To assess the clinical utility of fetal cardiovascular magnetic resonance imaging in cases in which fetal echocardiography could not visualize all relevant anatomy.

Design, Setting, and Participants

This cohort study was conducted between January 20, 2017, and June 29, 2020, at Skåne University Hospital (Lund, Sweden), a tertiary center for pediatric cardiology and thoracic surgery. Participants were fetuses referred for fetal cardiovascular magnetic resonance examination by a pediatric cardiologist after an inconclusive echocardiograph.

Exposures

Fetal cardiovascular magnetic resonance examination requested by the patient's pediatric cardiologist.

Main Outcomes and Measures

Any change in patient management because of diagnostic information gained from fetal cardiovascular magnetic resonance imaging.

Results

A total of 31 fetuses underwent cardiovascular magnetic resonance examination at a median gestational age of 36 weeks (range, 31-39 weeks). Overall, fetal cardiovascular magnetic resonance imaging had clinical utility, affecting patient management and/or parental counseling in 26 cases (84%). For aortic arch anatomy including signs of coarctation (20 fetuses), fetal cardiovascular magnetic resonance imaging added diagnostic information in 16 cases (80%). For assessment of univentricular vs biventricular outcome in borderline left ventricle, unbalanced atrioventricular septal defect, and pulmonary atresia with intact ventricular septum (15 fetuses), fetal cardiovascular magnetic resonance imaging visualized intracardiac anatomy and ventricular function, allowing assessment of outcome in 13 cases (87%). In 4 fetuses with hypoplastic left heart syndrome, fetal cardiovascular magnetic resonance imaging helped delivery planning in 3 cases (75%). Finally, fetal cardiovascular magnetic resonance imaging provided valuable information for parental counseling in 21 cases (68%).

Conclusions and Relevance

In this cohort study, fetal cardiovascular magnetic resonance imaging added clinically useful information to what was available from echocardiography. These findings suggest that fetal CMR has the potential to affect clinical decision-making in challenging cases of congenital heart defects with inconclusive data from echocardiography. Fetal cardiovascular magnetic resonance imaging showed an association with clinical decision-making, including mode of delivery and early postnatal care, as well as with parental counseling.

Quantification of end diastolic forward flow in two cases with pulmonary atresia with intact ventricular septum

Similar to patients with repaired tetralogy of Fallot, patients with repaired pulmonary atresia with intact ventricular septum may need a reintervention at a later stage. Although the role of MRI in the long-term follow-up of patients with repaired tetralogy of Fallot has been established, the same has not been established for patients with repaired pulmonary atresia with intact ventricular septum. To define this role, we quantified the end-diastolic forward flow by fractioning it by the total flow of the main pulmonary artery in two cases during their long-term follow up after biventricular repair. In case 1, a male patient had hepatic congestion and a high end-diastolic forward flow fraction and underwent surgical take down to one and one-half ventricle repair at the age of 18 years. In case 2, a female patient, currently 13 years old, has an increasing end-diastolic forward flow fraction. She is under close observation as a potential candidate for one and one-half ventricle repair in the near future. Both patients had a high end-diastolic forward flow fraction of the total right ventricle output, suggesting that end-diastolic forward flow fraction may become a possible become a possible indicator of the adequacy of biventricular repair and the optimal timing for re-intervention.

Fetal Cardiac Intervention for Pulmonary Atresia with Intact Ventricular Septum: International Fetal Cardiac Intervention Registry

INTRODUCTION

Invasive fetal cardiac intervention (FCI) for pulmonary atresia with intact ventricular septum (PAIVS) and critical pulmonary stenosis (PS) has been performed with small single-institution series reporting technical and physiological success. We present the first multicenter experience.

OBJECTIVES

Describe fetal and maternal characteristics of those being evaluated for FCI, including pregnancy/neonatal outcome data using the International Fetal Cardiac Intervention Registry (IFCIR).

METHODS

We queried the IFCIR for PAIVS/PS cases evaluated from January 2001 to April 2018 and reviewed maternal/fetal characteristics, procedural details, pregnancy and neonatal outcomes. Data were analyzed using standard descriptive statistics.

RESULTS

Of the 84 maternal/fetal dyads in the registry, 58 underwent pulmonary valvuloplasty at a median gestational age of 26.1 (21.9-31.0) weeks. Characteristics of fetuses undergoing FCI varied in terms of tricuspid valve (TV) size, TV regurgitation, and pulmonary valve patency. There were fetal complications in 55% of cases, including 7 deaths and 2 delayed fetal losses. Among those who underwent successful FCI, the absolute measurement of the TV increased by 0.32 (±0.17) mm/week from intervention to birth. Among 60 liveborn with known outcome, there was a higher percentage having a biventricular circulation following successful FCI (87 vs. 43%).

CONCLUSIONS

Our data suggest a possible benefit to fetal therapy for PAIVS/PS, though rates of technically unsuccessful procedures and procedure-related complications, including fetal loss were substantial. FCI criteria are extremely variable, making direct comparison to nonintervention patients challenging and potentially biased. More uniform FCI criteria for fetuses with PAIVS/PS are needed to avoid unnecessary procedures, expose only fetuses most likely to sustain a benefit, and to enable comparisons to be made with nonintervention patients.

A low threshold for neonatal intervention yields a high rate of biventricular outcomes in pulmonary atresia with intact ventricular septum

AIMS

Management strategies for pulmonary atresia with intact ventricular septum are variable and are based on right ventricular morphology and associated abnormalities. Catheter perforation of the pulmonary valve provides an alternative strategy to surgery in the neonatal period. We sought to assess the long-term outcome in terms of survival, re-intervention, and functional ventricular outcome in the setting of a 26-year single-centre experience of low threshold inclusion criteria for percutaneous valvotomy.

METHODS AND RESULTS

Retrospective analysis of patients diagnosed with pulmonary atresia with intact ventricular septum from 1990 to 2016 at a tertiary referral centre, was performed. Of 71 patients, 48 were brought to the catheterisation laboratory for intervention. Catheter valvotomy was successful in 45 patients (94%). Twenty-three patients (51%) also underwent ductus arteriosus stenting. The length of intensive care and hospital stay was significantly shorter, and early re-interventions were significantly reduced in the catheterisation group. There were eight deaths (17%); all within 35 days of the procedure. Of the survivors, only one has required a Fontan circulation. Twenty-eight patients (74%) have undergone biventricular repair and nine patients (24%) have one-and-a-half ventricle circulation. Following successful valvotomy, 80% of patients required further catheter-based or surgical interventions.

CONCLUSIONS

A low threshold for initial interventional management yielded a high rate of successful biventricular circulations. Although mortality was low in patients who survived the peri-procedural period, the rate of re-intervention remained high in all groups.

Neonatal Pulmonary Atresia With Intact Ventricular Septum-8-Year Surgical Experience at One Center

BACKGROUND

Surgical treatment of pulmonary atresia with intact ventricular septum (PA/IVS) in neonates is challenging because of the broad variations of right ventricular (RV) malformations. In this retrospective study, we summarized our 8-y experience in surgical management for neonatal PA/IVS patients.

METHODS

Thirty-four neonates with PA/IVS between July 1, 2006 and June 30, 2014, were reviewed. Patients were categorized into three groups: mild, moderate, and severe RV hypoplasia according to RV morphology and development. Patients were on regular follow-up for at least 5 y. Overall survival, complications, reinterventions, risk factors for mortality, and health status were evaluated.

RESULTS

21 patients (61.8%) were treated with biventricular repair, eight patients (23.5%) with Fontan procedure, and one patient (2.9%) with bidirectional Glenn procedure. There were four postprocedural mortalities and one late death. The 5-y survival rates after final surgical repair for mild, moderate, and severe RV hypoplasia groups were 100%, 100%, and 88.9%, respectively. The reintervention rates were 0% (0/4), 21.4% (3/14), and 55.6% (5/9) for the subgroups, respectively. At the latest follow-up, most patients had a status characterized as New York Heart Association class I (88.9%, 24/27).

CONCLUSIONS

Surgical management for PA/IVS in neonates should be individualized. Favorable early and long-term outcomes can be achieved in neonatal PA/IVS patients by individualized surgical strategies, regardless of the degree of RV hypoplasia. In spite of potential RV catch-up development, the degree of RV hypoplasia is a factor of paramount importance to assess PA/IVS in neonates.

Competing risks analysis of time-to-event data for cardiovascular surgeons

OBJECTIVES

The purpose of this article is to provide thoracic and cardiovascular surgeons with a practical step-by-step strategy to use in collaboration with a biostatistician for implementation of competing risks analysis when analyzing time-to-event data. Patients may have an outside event that precludes the event of interest. Traditional time-to-event analysis incorrectly assumes noninformative censoring in this scenario, which will lead to invalid results and conclusions.

METHODS

The steps are (1) to determine whether competing risks analysis is needed, (2) to perform a nonparametric analysis, (3) to perform a model-based analysis, (4) to interpret the results, and (5) to compare to traditional survival analysis methods. We apply our approach to a hypothetical cardiovascular surgery example in determining the hazard of mortality after the stage 3 Fontan operation associated with prematurity among patients with hypoplastic left heart syndrome who had successful completion of Norwood stage 1 while incorporating mortality during the stage 2 bidirectional Glenn procedure as a competing risk. We apply nonparametric, semiparametric, and parametric methods.

RESULTS

Although Cox regression establishes prematurity as a significant risk factor of mortality after stage 3 (hazard ratio, 1.26; 95% confidence interval, 1.06-1.50; P = .009), the competing risks analysis with the Fine-Gray model accounting for mortality after stage 2 determines that prematurity is not a significant predictor (hazard ratio, 1.07; 95% confidence interval, 0.90-1.27; P = .467).

CONCLUSIONS

This article provides a practical step-by-step approach for making competing risks more accessible for cardiac surgeons collaborating with a biostatistician in analyzing and interpreting time-to-event data.

Severe Pulmonary Stenosis or Atresia with Intact Ventricular Septum in the Fetus: The Natural History

PURPOSE

To assess the intrauterine course, the outcome, and to establish a new prenatal echocardiographic scoring system to predict biventricular (BV) versus univentricular (UV) outcome of fetuses with severe pulmonary stenosis or atresia with intact ventricular septum (PSAIVS).

METHODS

All cases of PSAIVS diagnosed prenatally over a period of 14years were retrospectively collected in 2 tertiary referral centers.

RESULTS

Forty-nine fetuses with PSIVS (n = 11) or PAIVS (n = 38) were identified prenatally. Nineteen (38.8%) fetuses had additional ventriculocoronary connections (VCCs) and 21 (42.9%) fetuses had right ventricular hypoplasia. Four (8.2%) pregnancies were terminated, 2 (4.1%) ended in intrauterine fetal death, 4 (8.2%) in neonatal death, and 5 (10.2%) children died in infancy or childhood, including one case with compassionate care. Thirty-four of 44 (77.3%) fetuses with the intention-to-treat were alive at latest follow-up, 25 (73.5%) with BV, and 9 (26.5%) with UV circulation. Most significant predictive markers of UV circulation were Vmax of tricuspid regurgitation (TR) <2 m/s, right ventricle/left ventricle length ratio ≤0.6, and presence of VCC. A scoring system including these 3 markers had 100% sensitivity and 100% specificity predicting an UV outcome if more than one of these criteria was fulfilled. All 25 liveborn infants that were suitable for BV repair survived, whereas only 9 out of 14 candidates for UV repair survived. None of the 14 fetuses with predicted UV outcome would have met the inclusion criteria for fetal intervention, as 10 of them had VCC and the remaining 4 had absent TR or Vmax <2 m/s.

CONCLUSION

The prognosis of prenatally diagnosed PSAIVS is good if BV circulation can be achieved, while postnatal mortality in UV circulation is high within the first 4 months of life. Postnatal outcome can be predicted prenatally with high accuracy using a simple scoring system. This information is mandatory for parental counseling and may be useful in selecting fetuses for intrauterine valvuloplasty.

Long-term outcomes of single-ventricle palliation for pulmonary atresia with intact ventricular septum: Fontan survivors remain at risk of late myocardial ischaemia and death

OBJECTIVES

The specific outcomes of patients with pulmonary atresia with intact ventricular septum late after Fontan palliation are unknown. Patients with smaller right ventricles and myocardial sinusoids are known to have worse survival in the first years of life. Whether the potential for coronary ischaemia affects the long-term outcomes of these patients after Fontan palliation is still unknown.

METHODS

All patients with pulmonary atresia with intact ventricular septum who underwent the Fontan procedure from 1984 to 2016 in Australia and New Zealand were identified, and preoperative, perioperative and follow-up data were collected.

RESULTS

Late follow-up data were available for 120 patients. The median length of follow-up after the Fontan procedure was 9.1 years (interquartile range 4.2-15.4 years). Late death occurred in 9% of patients (11/120). Six were sudden, unexpected deaths; 4 of those occurred in patients known to have right ventricle-dependent coronary circulation (RVDCC). Those with RVDCC had a higher incidence of sudden death (4/20 vs 2/100; P = 0.007). RVDCC was associated with late death (P = 0.01) and the development of myocardial ischaemia after Fontan completion (P < 0.001). The 10-year survival rate was 77% (95% confidence interval 56-100%) for patients with RVDCC vs 96% (95% confidence interval 92-100%) for patients without RVDCC.

CONCLUSIONS

Long-term survival of patients with pulmonary atresia with intact ventricular septum after the Fontan procedure is excellent, but patients with RVDCC remain susceptible to coronary ischaemia and sudden death. Closer surveillance and investigation for exercise-induced ischaemia may be necessary.

[Percutaneous management of pulmonary atresia with intact ventricular septum and critical pulmonary stenosis]

INTRODUCTION

Pulmonary atresia with intact ventricular septum and critical pulmonary stenosis in newborns encompasses a wide spectrum of disease, including cases with significant right ventricular hypoplasia and coronary artery to right ventricle fistulae, which may be considered a contraindication for decompression of the right ventricle. The aim of this study was to review the middle- and long-term outcomes of these patients over 20 years and identify differential factors between both groups, including patients with coronary artery fistulae.

PATIENTS AND METHODS

We performed a descriptive retrospective study by identifying all patients that received a diagnosis of pulmonary atresia with intact ventricular septum and critical pulmonary stenosis between January 1996 and January 2018. We collected and analysed data regarding right ventricular morphology, surgical management, percutaneous intervention and medium- and long-term outcomes.

RESULTS

51 patients were admitted. A total of 9 patients (17.6%) died during the followup. None of the deceased patients had coronary artery to right ventricle fistulae. The median length of follow up in the 42 survivors was 8.9 years (1-16). The functional class based on the latest revision of the New York Heart Association classification was 1.2 for the overall sample. Survivors of critical pulmonary stenosis had a functional class of 1.1, and survivors of pulmonary atresia with intact ventricular septum a functional class of 1.6. There were no differences based on the presence or absence of coronary artery to right ventricle fistulae.

CONCLUSIONS

Coronary artery to right ventricle fistulae may not be a contraindication for biventricular strategy. Patients with critical pulmonary stenosis had better outcomes compared to patients with pulmonary atresia with intact ventricular septum. The aggressive strategy of opening the pulmonary valve early on was associated with a good overall survival and correlated to a good functional class.

The outcome of adults born with pulmonary atresia: High morbidity and mortality irrespective of repair

OBJECTIVES

To describe the characteristics and long-term outcome of a large adult cohort with pulmonary atresia.

BACKGROUND

Patients with pulmonary atresia (PA) are a heterogeneous population in terms of anatomy, physiology and surgical history, and their management during adulthood remains challenging.

METHODS

Data on all patients with PA followed in our center between January 2000 and March 2015 were recorded. Patients were classified into the following groups: PA with ventricular septal defect (PA-VSD, 1), PA with intact ventricular septum (PA-IVS, 2) and other miscellaneous PA (PA-other, 3).

RESULTS

Two-hundred twenty-seven patients with PA were identified, 66.1% female, mean age 25.5 ± 8.7 years. Over a median follow-up of 8.8 years, 49 (21.6%) patients had died: heart failure (n = 21, 42.8%) and sudden cardiac death (n = 8, 16.3%) were the main causes. There was no significant difference in mortality between the 3 Groups (p = 0.12) or between repaired and unrepaired patients in Group 1 (p = 0.16). Systemic ventricular dysfunction and resting oxygen saturations were the strongest predictors of mortality. Additionally, 116 (51%) patients were hospitalized, driven mainly by the need for invasive procedures, heart failure and arrhythmias.

CONCLUSIONS

Adult survivors with pulmonary atresia have a high morbidity and mortality irrespective of underlying cardiac anatomy and previous reparative or palliative surgery. We present herewith predictors of outcome in adult life that may assist with their tertiary adult congenital care.

Myocardial strain abnormalities in fetuses with pulmonary atresia and intact ventricular septum

OBJECTIVES

Global and regional myocardial deformation have not been well described in fetuses with pulmonary atresia and intact ventricular septum (PA/IVS). Speckle-tracking echocardiography (STE), an angle-independent technique for assessing global and regional strain, may be a more sensitive way of determining ventricular systolic dysfunction compared with traditional 2D echocardiography. The aim of this study was to assess myocardial deformation in fetuses with PA/IVS compared with control fetuses and to determine if, in fetuses with PA/IVS, strain differs between those with and those without right ventricle-dependent coronary circulation (RVDCC).

METHODS

This was a retrospective analysis of fetuses with PA/IVS examined at two medical centers between June 2005 and October 2017. Left ventricular (LV) and right ventricular (RV) regional and global longitudinal strain (GLS) and strain rate were obtained using STE, and comparisons were made between fetuses with PA/IVS and gestational age (GA)-matched controls. Postnatal outcome was assessed, including the presence of RVDCC.

RESULTS

Fifty-seven fetuses with PA/IVS and 57 controls were analyzed at a mean GA of 26.5 ± 5 weeks. LV-GLS was significantly decreased in fetuses with PA/IVS compared with controls (-17.4 ± 1.7% vs -23.7 ± 2.0%, P < 0.001). LV strain rate was also significantly decreased (-1.01 ± 0.21/s vs -1.42 ± 0.20/s, P < 0.001). Fetuses with PA/IVS had decreased strain in all segments. Similarly, RV strain was significantly decreased in fetuses with PA/IVS (-11.6 ± 3.8% vs -24.6 ± 2.5%, P < 0.0001). Thirty-six patients had postnatal cardiac catheterization performed to define coronary anatomy; 10 fetuses had RVDCC. Fetuses with RVDCC had decreased LV strain compared with those without (-15.8 ± 1.2% vs -17.9 ± 1.7%, P = 0.009). RV strain was also decreased in fetuses with RVDCC vs those without (-7.0 ± 2.9% vs -12.1 ± 3.2%, P = 0.0004).

CONCLUSIONS

Fetuses with PA/IVS have decreased global and regional LV and RV strain compared with controls. The finding of decreased LV strain may be due to altered ventricular mechanics in the context of a hypertensive right ventricle and/or abnormal coronary perfusion. Moreover, fetuses that were found to have RVDCC postnatally had decreased LV and RV strain compared with those that did not. These results encourage further investigation to assess whether fetal ventricular strain could be a prenatal predictor of RVDCC. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Differences in Right Ventricular Physiologic Response to Chronic Volume Load in Patients with Repaired Pulmonary Atresia Intact Ventricular Septum/Critical Pulmonary Stenosis Versus Tetralogy of Fallot

BACKGROUND

Patients with pulmonary atresia with intact ventricular septum and critical pulmonary stenosis (PAIVS/CPS) have wide variation in right ventricle (RV) size, systolic function, and diastolic function at birth. Establishment of antegrade pulmonary blood flow creates the potential for RV dilation from chronic pulmonary insufficiency. Future surgical decisions are based on RV size and function, largely supported by longitudinal studies of patients with Tetralogy of Fallot (TOF). Given potential differences in RV physiology and lack of similar data in PAIVS/CPS, the objective of this study was to determine differences in RV size, systolic function, and diastolic function between patients with PAIVS/CPS versus TOF.

METHODS

We retrospectively collected cardiovascular magnetic resonance (CMR) data in 27 patients with PAIVS/CPS (ages 13.3 ± 8.8 years) and 78 with TOF (11.4 ± 5.4 years). RV volumes, ejection fraction (EF), regurgitant fraction, end-diastolic forward flow across the pulmonary valve, and right atrial cross-sectional area were calculated.

RESULTS

There was no difference between the groups in RV end-diastolic volume (RVEDVi), RVEF, or pulmonary regurgitation. RVEF tended to decrease in TOF when RVEDVi exceeded 164 ml/m². In PAIVS/CPS, RVEDVi less frequently reached 164 ml/m² and was not associated with RVEF. There was worse RV diastolic dysfunction in PAIVS/CPS, with 1.5 times larger right atrial area and two times higher pulmonary end-diastolic forward flow (p < 0.0001).

CONCLUSIONS

Patients with PAIVS/CPS have similar RV size, systolic function, and pulmonary regurgitation as TOF. However, impaired RV diastolic function may limit extremes of RV dilatation and impact long-term management of PAIVS/CPS.

Younger age remains a risk factor for prolonged length of stay after bidirectional cavopulmonary anastomosis

OBJECTIVE

This study sets out to determine the influence of age at the time of surgery as a risk factor for post-operative length of stay after bidirectional cavopulmonary anastomosis.

METHODS

All patients undergoing a Glenn procedure between January 2010 and July 2015 were included in this retrospective cohort study. Demographic data were examined. Standard descriptive statistics was used. A univariable analysis was conducted using the appropriate test based on data distribution. A propensity score for balancing the group difference was included in the multi-variable analysis, which was then completed using predictors from the univariable analysis that achieved significance of p&lt;0.1.

RESULTS

Over the study period, 50 patients met the inclusion criteria. Patients were separated into two cohorts of ⩾4 months (28 patients) and &lt;4 months (22 patients). Other than height and weight, the two cohorts were indistinguishable in their pre-operative saturation, medications, catheterisation haemodynamics, atrioventricular valve regurgitation, and ventricular function. After adjusting group differences, younger age was associated with longer post-operative length of hospitalisation - adjusted mean 15 (±2.53) versus 8 (±2.15) days (p=0.03). In a multi-variable regression analysis, in addition to ventricular dysfunction (β coefficient=8.8, p=0.05), Glenn procedures performed before 4 months were independently associated with longer length of stay (β coefficient=-6.9, p=0.03).

CONCLUSION

We found that Glenn procedures performed after 4 months of age had shorter post-operative length of stay when compared to a younger cohort. These findings suggest that balancing timing of surgery to decrease the inter-stage period should take into consideration differences in post-operative recovery with earlier operations.

Long-term outcomes after intervention for pulmonary atresia with intact ventricular septum

OBJECTIVE

Pulmonary atresia with intact ventricular septum (PA/IVS) can be treated by various operative and catheter-based interventions. We aim to understand the long-term transplant-free survival of patients with PA/IVS by treatment strategy.

METHODS

Cohort study from the Pediatric Cardiac Care Consortium, a multi-institutional registry with prospectively acquired outcome data after linkage with the National Death Index and the Organ Procurement and Transplantation Network.

RESULTS

Eligible patients underwent neonatal surgery or catheter-based intervention for PA/IVS between 1982 and 2003 (median follow-up of 16.7 years, IQR: 12.6-22.7). Over the study period, 616 patients with PA/IVS underwent one of three initial interventions: aortopulmonary shunt, right ventricular decompression or both. Risk factors for death at initial intervention included earlier birth era (1982-1992), chromosomal abnormality and atresia of one or both coronary ostia. Among survivors of neonatal hospitalisation (n=491), there were 99 deaths (4 post-transplant) and 10 transplants (median age of death or transplant 0.7 years, IQR: 0.3-1.8 years). Definite repair or last-stage palliation was achieved in the form of completed two-ventricle repair (n=201), one-and-a-half ventricle (n=39) or Fontan (n=96). Overall 20-year survival was 66%, but for patients discharged alive after definitive repair, it reached 97.6% for single-ventricle patients, 90.9% for those with one-and-a-half ventricle and 98.0% for those with complete two-ventricle repair (log-rank p=0.052).

CONCLUSIONS

Transplant-free survival in PA/IVS is poor due to significant infantile and interstage mortality. Survival into early adulthood is excellent for patients reaching completion of their intended path independent of type of repair.

Congenital Cardiac Defects That Are Borderline Candidates for Biventricular Repair

This article discusses congenital heart defects that are marginal candidates for biventricular repair and highlights the anatomic considerations upon which the surgical decision is based. Specifically, the article reviews the importance of capacitance and compliance of the ventricles and their associated atrioventricular valves. For each of the defects discussed, the imaging modalities used to diagnose a marginal ventricle are reviewed and the surgical decision-making process is outlined. The article also reviews immediate postoperative treatment of these patients and when to consider biventricular repair of a marginal lesion to be a failure.

Pulmonary Atresia With Intact Ventricular Septum With Borderline Tricuspid Valve: How Small Is Too Small

PA/IVS is a rare, heterogenous congenital heart defect anatomically defined by complete obstruction to the right ventricular outflow tract with varying degrees of hypoplasia of the right ventricle and tricuspid valve. This lesion can have associated coronary artery anomalies and, in some cases, right ventricular-dependent coronary circulation. Due to the wide spectrum of presenting anatomic and clinical features, the treatment options are often dictated by the degree of development of the tricuspid valve and right ventricle. The purpose of this review is to discuss the spectrum of pulmonary atresia with intact ventricular septum morphologies and to evaluate the surgical decision-making process and approaches to surgical repair with respect to the impact of hypoplastic right-sided cardiac features.

Incremental History of the Congenital Heart Surgeons’ Society (2014-2018)

The history of the first 41 years of the Congenital Heart Surgeons Society (CHSS) was recorded in 2015 which chronicled the metamorphosis of a small informal meeting into a mature organization with bylaws, officers, committees, funded research, the Kirklin-Ashburn Fellowship, and a vision to become the premier organization of congenital heart surgery in North America. Chief among these transformations was the implementation and development of the CHSS Data Center. Member participation, fellowship education, and significant outcomes research have been the hallmark of the CHSS. This incremental historical review highlights continued CHSS sentinel advances. Fifty-three CHSS Data Center manuscripts have been published. Citation scores (number of literature citations that each manuscript has accrued) have been collated and analyzed by cohort study. The average citation score for all manuscripts was 75.4 ± 76.3 (range: 1-333). The Kirklin/Ashburn Fellowship continues to thrive with academic achievements and generous contributions to the endowment. The World Journal of Pediatric and Congenital Heart Surgery has been adopted as the official organ of the CHSS. A Past President’s Dinner has been inaugurated serving as a senior advisory committee to the Executive Council. Toronto Work Weekends continue. Congenital Heart Surgeons Society growth has accrued to 159 active members and 82 institutional members. Future considerations include the size, content, and duration of the annual meeting; the potential for increased membership; and political penetrance into national cardiothoracic governing organizations regarding committee appointments, executive council representation, and education initiatives. Congenital Heart Surgeons Society has achieved numerous advances during this incremental period.

Echocardiographic parameters associated with biventricular circulation and right ventricular growth following right ventricular decompression in patients with pulmonary atresia and intact ventricular septum: Results from a multicenter study

BACKGROUND

In patients with pulmonary atresia, intact ventricular septum (PA/IVS) following right ventricular (RV) decompression, RV size and morphology drive clinical outcome. Our objectives were to (1) identify baseline and postdecompression echocardiographic parameters associated with 2V circulation, (2) identify echocardiographic parameters associated with RV growth and (3) describe changes in measures of RV size and changes in RV loading conditions.

METHODS

We performed a retrospective analysis of patients who underwent RV decompression for PA/IVS at four centers. We analyzed echocardiograms at baseline, postdecompression, and at follow up (closest to 1-year or prior to Glenn circulation).

RESULTS

Eighty-one patients were included. At last follow-up, 70 (86%) patients had 2V circulations, 7 (9%) had 1.5 ventricle circulations, and 4 (5%) had single ventricle circulations. Follow-up echocardiograms were available in 43 (53%) patients. The majority of patients had improved RV systolic function, less tricuspid regurgitation (TR), and more left-to-right atrial shunting at a median of 350 days after decompression. Multivariable analysis demonstrated that larger baseline tricuspid valve (TV) z-score (P = .017), ≥ moderate baseline TR (P = .045) and smaller baseline RV area (P < .001) were associated with larger increases in RV area. Baseline RV area ≥6 cm² /m² had 93% sensitivity and 80% specificity for identifying patients who ultimately achieved 2V circulation. All patients with RV area ≥8 cm² /m² at follow up achieved 2V circulation. This finding was confirmed in a validation cohort from a separate center (N = 25). Factors associated with achieving RV area ≥8 cm² /m² included larger TV z-score (P = .004), ≥ moderate baseline TR (P = .031), and ≥ moderate postdecompression pulmonary regurgitation (P = .002).

CONCLUSIONS

Patients with PA/IVS and smaller TV annuli are at risk for poor RV growth. Volume-loading conditions signal increased capacity for growth sufficient for 2V circulation.

Transcatheter perforation of atretic pulmonary valve by the stiff end of a coronary wire in neonates with pulmonary atresia with intact ventricular septum: A solution in developing countries

Objectives

To evaluate the safety of using the stiff end of a coronary wire to perforate an atretic pulmonary valve (PV) in patients with pulmonary atresia with intact ventricular septum (PAIVS).

Background

Radiofrequency perforation is an accepted modality to perforate the PV in patients PAIVS. However, the high cost precludes its widespread use.

Patients and methods

This is a single-center experience that spanned from March 2013 to January 2016 and involved 13 neonates who were severely cyanotic with PAIVS and with ductal-dependent pulmonary circulation. The stiff end of a coronary wire was used to perforate the atretic PV anterogradely, followed by balloon pulmonary valvuloplasty.

Results

The mean age of patients was 3.9 ± 2.7 days and their mean weight was 2.8 ± 0.19 kg. The mean oxygen saturation was 77.1 ± 3.2%. All had membranous pulmonary atresia, with patent infundibulum and tripartite right ventricle. The valve was successfully perforated in 11 out of 13 patients. Death occurred in two patients (15.4%) owing to heart failure and sepsis. Patent ductus arteriosus stenting was performed 2 days after the procedure in one patient because of cyanosis followed by one and half ventricle repair at of age 5 months. Two patients (15.4%) had one and a half ventricle repair at age of 5 months and 6 months owing to insufficient anterograde pulmonary flow. Two patients (15.4%) underwent second intervention with balloon dilatation of the valve. The remaining seven patients (53.8%) had no further intervention. Two cases (15.4%) had femoral artery thrombosis treated with streptokinase. The mean duration of follow-up was 13.17 ± 7 months. There was significant improvement in the degree of tricuspid incompetence. There was a significant growth in the tricuspid valve annulus during the follow-up (the mean Z score increased from −0.8 ± 0.9 to 0.1 ± 0.9) (p = 0.003). There was also a significant increase in the tricuspid valve annulus/mitral valve annulus ratio as its mean increased from 0.73 ± 0.10 to 0.86 ± 0.11 during follow-up (p < 0.001).

Conclusion

Perforation of the atretic PV in selected cases with membranous atresia and patent infundibulum using the stiff end of a coronary wire is an effective alternative to using radiofrequency perforation.

Pulmonary Atresia With an Intact Ventricular Septum: Preoperative Physiology, Imaging, and Management

Pulmonary atresia with intact ventricular septum (PA-IVS) is a rare complex cyanotic congenital heart disease with heterogeneous morphological variation. Prenatal diagnosis allows for developing a safe plan for delivery and postnatal management. While transthoracic echocardiography allows for detailed delineation of the cardiac anatomy, additional imaging modalities such as computed tomography, magnetic resonance imaging, and catheterization may be necessary to further outline features of the cardiac anatomy, specifically coronary artery anatomy. The size of the tricuspid valve and right ventricular cavity as well as the presence of right ventricle–dependent coronary circulation help to dichotomize between biventricular repair versus univentricular palliation or heart transplantation, as well as predicting the expected survival. The delineation and understanding of these features help to dictate both medical and surgical management.

Surgical strategy and outcomes for the delayed diagnosis of pulmonary atresia with intact ventricular septum

BACKGROUND

In the present study, we summarize the experiences and evaluate clinical outcomes for the delayed diagnosis of pulmonary atresia with intact ventricular septum (PAIVS) patients when undergoing an initial visit and diagnosis in our heart center.

METHODS

Fifty-eight cases of delayed diagnosis of PAIVS in patients aged more than 6 months between January 2006 and June 2016 were reviewed in our hospital. The median age at initial diagnosis was 12.2 months (range, 6.1-79.6 months). Forty-five cases eventually reached definitive repair. Survival, risk factors for death, and clinical status after definitive repair were assessed.

RESULTS

Among patients who completed definitive repair, the Fontan procedure was performed in a large proportion of older PAIVS children (42.2%, 19/45), while only a few patients received biventricular repair (22.2%, 10/45). The medium-term (10-year) survival rates of biventricular repair, 1.5-ventricular repair, and univentricular palliation were 100.0%, 93.3%, and 81.2%, respectively. At the latest follow-up, most patients had a good clinical status after definitive repairs, with a low re-operation rate.

CONCLUSIONS

A large proportion of the delayed diagnosis of PAIVS patients had to receive univentricular palliation because of limited potential for right ventricular growth. However, optimal definitive repairs could also have been achieved in these patients with a low mortality rate.