Long-term functional health status and exercise test variables for patients with pulmonary atresia with intact ventricular septum: a Congenital Heart Surgeons Society study

Research Enterprise of the Congenital Heart Surgeons' Society 2018 to 2023: History, Accomplishments, Transformation, and Challenges

The history of the research arm of the Congenital Heart Surgeons' Society (CHSS) through 2017 was contained within two prior publications that covered CHSS history in general. The present article is the first to focus explicitly on the research enterprise, with emphasis on the period 2018 to 2023. During this time, the challenges of continuing to build multiple cohorts with lifelong follow-up and to transform the enterprise to a premiere research organization became manifest. Although continuing its commitment to produce impactful research results and to educate the Kirklin/Ashburn Fellow, the research team devoted considerable effort to defining the problems of cohort relevance, workflow, data management, long-term patient follow-up, CHSS member engagement, and the regulatory burden. The team wrote a proposal outlining ways to solve the challenges. A major change from a single-institution "Data Center" to a two-institution Center for Research & Quality (CRQ) was made, assuring increased faculty members and resources. The proposed changes to structure and process began execution in mid-2022. A second Kirklin/Ashburn Fellowship position was created. Between 2018 and 2022, the CRQ produced 17 publications and launched five new research initiatives. This article chronicles the exciting five-year period in which the CHSS research enterprise began a transformation with the intent to become the premiere research organization in the world in the specialty of congenital cardiac surgery.

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.

Exercise Capacity in Patients with Pulmonary Atresia with Intact Ventricular Septum: Does the Type of Surgical Repair Matter?

Two standard surgical palliative options for neonates born with pulmonary atresia and intact ventricular septum (PA/IVS) include uni-or biventricular repair. Whenever feasible, the biventricular repair is considered to have better exercise capacity (XC) and outcomes. However, there is a paucity of data comparing objective XC between these two surgical techniques. Our aim was to compare XC, including longitudinal changes in patients with PA/IVS following uni-biventricular repair. We performed a single-center retrospective study of survivors with repaired PA/IVS who underwent comprehensive treadmill cardiopulmonary exercise testing. Initial and latest exercise parameters were compared for longitudinal analysis. Demographic and exercise parameters were collated. Peak oxygen uptake (VO₂ in ml/kg/min), an indicator of maximal aerobic capacity, peak heart rate, and other measures of spirometry performed at the same time were collected. Recorded parameters included, (a) Percentage of predicted VO₂ (% VO2) normalized for age, weight, height, and gender, (b) % oxygen (O₂) pulse, (c) anaerobic threshold (AT), (d) Chronotropic index (CI), (e) % Breathing reserve, (f) Forced vital capacity (FVC), (g) % Forced Expiratory volume in 1 s (FEV1), (h) Maximum voluntary ventilation (MVV), and (i) VE/VCO₂. Appropriate statistical tests were performed, and a p value < 0.05 was considered significant. A total of 35 patients (43% male, 57% univentricular repair) were included, with a mean (SD) age of 20.1(7.5) years. Patients with univentricular palliation demonstrated significantly impaired peak heart rate, chronotropic index (0.50 ± 0.2 vs. 0.90 ± 0.1, p = 0.02), VE/VCO₂ (35.4 ± 5.0 vs. 30.2 ± 2.8, p = 0.001), and %FVC (78.3 ± 8.3 vs. 88.6 ± 15.1, p = 0.02). There was a trend towards reduction in % VO₂ in the Fontan patients though it was statistically similar between the groups (68.4 ± 21.4 vs. 81.2 ± 18.9, p = 0.07). Longitudinal data were available for 11 patients in each group, and there was no longitudinal decline in their exercise parameters over similar intermediate follow-up duration [6.8 (UV) vs. 5.3 (BV) years]. We conclude that young survivors with PA/IVS with prior univentricular palliation demonstrated an objective impairment in their chronotropic parameters compared with the biventricular repair. However, this did not translate into a significant difference in their exercise capacity. There was no longitudinal decline in exercise capacity or other parameters over intermediate follow-up.

Prognostic Implications of Right Atrial Dysfunction in Adults With Pulmonary Atresia and Intact Ventricular Septum

Background

Pulmonary atresia with intact ventricular septum is associated with significant morbidity and mortality, but there are limited data to guide risk stratification in this population. The purpose of this study was to assess the role right atrial (RA) strain indices for prognostication in this population.

Methods

This is a retrospective study of adults (aged ≥18 years) with pulmonary atresia with intact ventricular septum and biventricular repair who underwent echocardiogram (2003-2019). RA reservoir strain was used as the primary metric of RA function, and RA dysfunction was defined as RA reservoir strain <31%. Clinical outcomes were assessed using 4 different indices: (1) functional impairment (New York Heart Association II-IV); (2) hepatorenal dysfunction (model for end-stage liver disease excluding international normalized ratio score >11); (3) incident atrial arrhythmias/heart failure hospitalization; (4) heart transplant/cardiovascular death.

Results

Of the 43 patients in the study, RA strain imaging was feasible in 95%, and RA dysfunction was present in 95%. Of the 43 patients, 67% and 49% had functional impairment and hepatorenal dysfunction, respectively; 44% developed incident atrial arrhythmia/heart failure hospitalization and 14% died during follow-up. RA reservoir strain was independently associated with all indices of clinical outcomes.

Conclusion

Collectively, these data suggest that RA strain imaging was feasible in almost all patients and can be used for risk stratification in this population. There was a high prevalence of comorbidities including hepatorenal dysfunction. Further studies are needed to determine the prognostic implications of hepatorenal dysfunction (a previously unrecognized complication), and whether using RA function indices for clinical decision making will lead to improved outcomes in this population.

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.

Safe Decompression of the Right Ventricle for PAIVS in Neonates With Coronary Fistulae: Including the Selective Use of Fistula Ligation to Avoid Coronary Steal

BACKGROUND

There are a number of surgical and interventional treatment options for infants with pulmonary atresia with intact ventricular septum (PAIVS). In our practice, we characterize coronary fistulae and interruptions with angiography in the newborn and have developed a strategy to safely decompress the right ventricle in association with ligation of fistulae if necessary.

METHODS

All infants operated for PAIVS at age < 60 days from 1999 to 2018 were retrospectively studied. Pre- and postoperative variables were collected, angiograms were reviewed, and a territory score was created to grade the severity of coronary abnormalities. This study focused on the subgroup of patients who had early surgical decompression of the right ventricle.

RESULTS

A total of 77 patients were included, with a mean follow-up of 8.6 years. Of these, 55 (71%) had coronary fistulae, including 28 (36%) with coronary artery interruption. Right ventricular decompression (RVD) was performed in 47 (60.5%) patients. There was no 30-day mortality in those who underwent RVD, whereas 6 (20%) without RVD died within 30 days (P = .003). Ten-year survival was 97.8% and 73.3% for RVD and non-RVD, respectively. In order to prevent coronary steal, 17 patients underwent coronary fistula ligation as their RV was decompressed with 100% early and late survival.

CONCLUSION

Early and late survival in infants with PAIVS is better if the RV can be decompressed. Coronary fistula ligation with RVD has been introduced without an adverse outcome in selected patients with large fistulae.

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.

Health-Related Quality of Life in Children, Adolescents, and Adults With a Fontan Circulation: A Meta-Analysis

Background

People with a Fontan circulation experience a range of physical, psychosocial and neurodevelopmental challenges alongside, or caused by, their cardiac condition, with significant consequences for health‐related quality of life (HRQOL). We meta‐analyzed HRQOL outcomes reported by people with a Fontan circulation or their proxies and evaluated predictors of poorer HRQOL.

Methods and Results

Six electronic databases were searched for peer‐reviewed, English‐language articles published before March 2019. Standardized mean differences (SMD) were calculated using fixed and random‐effects models. Fifty articles reporting on 29 unique studies capturing HRQOL outcomes for 2793 people with a Fontan circulation and 1437 parent‐proxies were analyzed. HRQOL was lower in individuals with a Fontan circulation compared with healthy referents or normative samples (SMD, −0.92; 95% CI, −1.36 to −0.48; P<0.001). Lower scores were reported across all HRQOL domains, with the largest differences found for physical (SMD, −0.90; 95% CI, −1.13 to −0.67; P<0.001) and school/work functioning (SMD, −0.71; 95% CI, −0.90 to −0.52; P<0.001). Meta‐regression analyses found no significant predictors of self‐reported physical functioning, but older age at Fontan operation was associated with poorer emotional functioning (β=−0.124; P=0.004), and diagnosis of hypoplastic left heart was associated with poorer social functioning (β=−0.007; P=0.048). Sensitivity analyses showed use of the PedsQL Core Module was associated with lower HRQOL scores compared with the Short‐Form Health Survey‐36.

Conclusions

HRQOL outcomes for people with a Fontan circulation are lower than the general population. Optimal care acknowledges the lifelong impact of the Fontan circulation on HRQOL and offers targeted strategies to improve outcomes for this growing population.

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.

[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.

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.

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.

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.

Sociodemographic Factors and Survival of Infants With Congenital Heart Defects

OBJECTIVES

To examine the first-year survival of infants with congenital heart defects (CHDs) and investigate the potential role of socioeconomic and demographic factors on survival.

METHODS

Subjects included 15 533 infants with CHDs born between 2004 and 2013 ascertained by the NC Birth Defects Monitoring Program. We classified CHDs into the following 3 groups: critical univentricular (n = 575), critical biventricular (n = 1494), and noncritical biventricular (n = 13 345). We determined vital status and age at death through linkage to state vital records and used geocoded maternal residence at birth to obtain census information for study subjects. We calculated Kaplan-Meier survival estimates by maternal and infant characteristics and derived hazard ratios from Cox proportional hazard models for selected exposures.

RESULTS

Among all infants with CHDs, there were 1289 deaths (8.3%) in the first year. Among infants with univentricular defects, 61.6% (95% confidence interval [CI]: 57.7%-65.7%) survived. Survival among infants with univentricular defects was considerably better for those whose fathers were ≥35 years old (71.6%; 95% CI: 63.8%-80.3%) compared with those whose fathers were younger (59.7%; 95% CI: 54.6%-65.2%). Factors associated with survival among infants with any biventricular defect included maternal education, race and/or ethnicity, marital status, and delivery at a heart center. The hazard of infant mortality was greatest among non-Hispanic African American mothers.

CONCLUSIONS

Survival among infants with critical univentricular CHDs was less variable across sociodemographic categories compared with survival among infants with biventricular CHDs. Sociodemographic differences in survival among infants with less severe CHDs reinforces the importance of ensuring culturally effective pediatric care for at-risk infants and their families.

The Lymphatic System: The Achilles Heel of the Fontan-Kreutzer Circulation

In spite of excellent long term survival the Fontan Kreutzer procedure commonly presents late failure due to end-organ damage. Several advances have been described to refine single ventricle management and surgical techniques. However, very little research has been dedicated to the lymphatic circulation in the precarious Fontan hemodynamic state. The lymphatic circulation is clearly affected since there is increased lymph production, which requires to be drained at a similar or higher pressure than it is produced, commonly resulting in chronic lymphedema. Chronic lymphedema induces fibrosis and end-organ failure even in normal circulation. Diverting lymph drainage to the low-pressured systemic atrium in Fontan may represent a valid alternative for the treatment of devastating complications as protein-losing enteropathy and plastic bronchitis and may prevent or decrease the development of end-organ fibrosis or failure.

Aortic perfusion score for pulmonary atresia with intact ventricular septum: An antegrade coronary perfusion scoring system that is predictive of need for transplant and mortality

BACKGROUND

Pulmonary atresia with intact ventricular septum is a unique congenital malformation of the heart in which patients may undergo single-, two- or 1½- ventricle repair. Size of the tricuspid valve annulus, morphology of the right ventricle and presence of ventriculocoronary connections can all impact the selection of appropriate palliative strategy. We developed the aortic perfusion score, a novel scoring system based on anterograde coronary perfusion with the aim of being able to identify patients at risk for death or transplant.

METHODS

A retrospective study was conducted. Patients were included if an initial catheterization was done prior to any intervention. Each patient was assigned an aortic perfusion score based on the amount of antegrade perfusion to the four main coronary arteries. Various characteristics, including aortic perfusion score, were compared between those who required transplant or died during follow-up vs those who did not. Receiver operator curve analysis was done to determine a cutoff point predictive of a composite endpoint of death or transplant.

RESULTS

A total of 64 patients were included in the analysis with 10 reaching the composite outcome. An aortic perfusion score of 227.5 predicted the endpoint with a sensitivity of 90% and a specificity of 83%. For each 1-point increase in the APS, the odds of death or transplant decreased by 1.7%.

CONCLUSION

The aortic perfusion score can be used to predict a composite endpoint of death or transplant and may be helpful in selecting patients that should be listed for transplant.

Optimal Z-Score Use in Surgical Decision-Making in Pulmonary Atresia With Intact Ventricular Septum

Objectives:

In the surgical treatment of pulmonary atresia with intact ventricular septum, the size of the tricuspid valve annulus (as measured by z-scores) has emerged as a significant factor in deciding which repair to perform. Various tricuspid valve annulus z-scores are reported as “cutoffs” for successful biventricular repair. We aimed to determine whether the use of different z-score data sets contributed to the gross variation in “cutoffs” for successful biventricular repair reported in the literature.

Methods:

A single search was made of PubMed using the “advanced” setting with the following search terms: pulmonary, atresia, intact, septum, z, and score. The filters “title” and “title/abstract” were used for the first four and last two terms, respectively; the instruction “AND” combined all terms. Articles that identified which z-score data set was used in patients with biventricular repairs were included.

Results:

From 13 articles, 1,392 patients were studied, 410 (29.5%) of which achieved biventricular repair. Three z-score data sets were quoted; mean tricuspid valve annulus z-scores in biventricular repair patients ranged between −0.53 and −5.1. After correcting for discrepancies between z-score data sets, no study reported a mean tricuspid valve annulus z-score <−2.8 in biventricular repair patients and 83.3% reported mean tricuspid valve annuli z-scores >−1.7.

Conclusion:

The use of varied tricuspid valve annuli z-score data sets may have contributed to gross variations in reported “cutoffs” for successful biventricular repair. This could lead to inappropriate surgical pathway allocation.

Outcomes of Radiofrequency Perforation for Pulmonary Atresia and Intact Ventricular Septum: A Single-Centre Experience

Percutaneous radiofrequency perforation (RFP) of the pulmonary valve is used as a primary therapy in neonates with pulmonary atresia and intact ventricular septum (PAIVS). We sought to determine the safety and efficacy of RFP for PAIVS in a single center and assess the pre-intervention anatomical parameters associated with a biventricular outcome. We retrospectively reviewed all cases of PAIVS treated with RFP at a single center from 1999 through 2012. We collected baseline imaging data, technical aspects of the procedure, adverse events and outcomes. RFP was attempted in 18 patients with 17 successful procedures. There was no mortality; one patient had an acute complication requiring surgical intervention. All were alive at the most recent follow-up (median 4.9 years; IQR = 2.0-6.8 years), 12/17 (71%) had a biventricular circulation, 2/17 (12%) had a 1½ ventricle repair, 2/17 (12%) had a univentricular repair and 1/17 was lost to follow-up. A biventricular outcome in patients with PAIVS was associated with the pre-intervention tricuspid valve/mitral valve (TV/MV) ratio and tricuspid valve (TV) z-score. The median TV/MV ratio for patients who underwent a biventricular repair and a non-biventricular repair was 0.82 (IQR = 0.71-0.90) and 0.59 (IQR = 0.39-0.76), P = 0.036, respectively. The median TV z-scores were -3.2 [(-4.9 to -2.6), and -6.8 (-9.7 to -4.8] P = 0.036 for the biventricular and non-biventricular groups, respectively. RFP is a safe primary therapy for PAIVS. With appropriate patient selection, RFP will often result in a biventricular circulation. Both the TV/MV and TV z-score were found to be a predictor of a biventricular outcome in our cohort.

Staged Biventricular Repair-Oriented Strategy in Borderline Biventricular Repair Candidates with Ventricular Septal Defect

Although borderline biventricular repair (BVR) candidates unsuitable for primary BVR are often subjected to single-ventricle repair (SVR), some of them reach BVR by staged strategy. We evaluated our staged BVR-oriented strategy in borderline BVR candidates with ventricular septal defect (VSD) in whom a BVR/SVR decision was deferred beyond the neonatal period. Forty-two patients were treated with the approach between 1991 and 2012. They had been followed toward BVR until it was judged impossible. Outcomes, time course toward definitive repair (DR: BVR, SVR, or 1 + 1/2 ventricle repair), and hemodynamics were reviewed. A total of 57 palliative surgeries were performed before BVR or bidirectional Glenn (BDG), namely procedures to control pulmonary blood flow in 40, to improve mixing in 5, and to promote left ventricle (LV) growth in 5. LV growth was achieved in four patients. There were three cardiac deaths. Except for four awaiting patients, 19 reached BVR (50 %), 11 patients were converted to other than BVR, and 28 patients achieved DR (74 %) at the median age of 30.9 months. Cardiac cath before BVR or BDG performed at the median age of 22.5 months revealed well-preserved pulmonary vasculature with the median pulmonary artery pressure of 14 mmHg, except three patients unsuitable for SVR. In conclusion, our staged BVR-oriented strategy required longer time course and more complex palliative surgeries compared with a simple SVR strategy. Leaving open the possibility of a late crossover to an SVR pathway is mandatory when adopting staged BVR-oriented strategy in these complex patients.

Decision-Making for Surgery in the Management of Patients with Univentricular Heart

A series of technical refinements over the past 30 years, in combination with advances in perioperative management, have resulted in dramatic improvements in the survival of patients with univentricular heart. While the goal of single-ventricle palliation remains unchanged - normalization of the pressure and volume loads on the systemic ventricle, the strategies to achieve that goal have become more diverse. Optimal palliation relies on a thorough understanding of the changing physiology over the first years of life and the risks and consequences of each palliative strategy. This review describes how to optimize surgical decision-making in univentricular patients based on a current understanding of anatomy, physiology, and surgical palliation.

Tachyarrhythmias and catheter ablation in adult congenital heart disease

Advances in surgical technique have had an immense impact on longevity and quality of life in patients with congenital heart disease. However, an inevitable consequence of these surgical successes is the creation of a unique patient population whose anatomy, surgical history and haemodynamics result in the development of a challenging and complex arrhythmia substrate. Furthermore, this patient group remains susceptible to the arrhythmias seen in the general adult population. It is through a thorough appreciation of the cardiac structural defect, the surgical corrective approach, and haemodynamic impact that the most effective arrhythmia care can be delivered. Catheter ablation techniques offer a highly effective management option but require a meticulous attention to the real-time integration of anatomical and electrophysiological information to identify and eliminate the culprit arrhythmia substrate. This review describes the current approach to the interventional management of patients with tachyarrhythmias in the context of congenital heart disease.

Linking the congenital heart surgery databases of the Society of Thoracic Surgeons and the Congenital Heart Surgeons' Society: part 1--rationale and methodology

PURPOSE

The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) is the largest Registry in the world of patients who have undergone congenital and pediatric cardiac surgical operations. The Congenital Heart Surgeons' Society Database (CHSS-D) is an Academic Database designed for specialized detailed analyses of specific congenital cardiac malformations and related treatment strategies. The goal of this project was to create a link between the STS-CHSD and the CHSS-D in order to facilitate studies not possible using either individual database alone and to help identify patients who are potentially eligible for enrollment in CHSS studies.

METHODS

Centers were classified on the basis of participation in the STS-CHSD, the CHSS-D, or both. Five matrices, based on CHSS inclusionary criteria and STS-CHSD codes, were created to facilitate the automated identification of patients in the STS-CHSD who meet eligibility criteria for the five active CHSS studies. The matrices were evaluated with a manual adjudication process and were iteratively refined. The sensitivity and specificity of the original matrices and the refined matrices were assessed.

RESULTS

In January 2012, a total of 100 centers participated in the STS-CHSD and 74 centers participated in the CHSS. A total of 70 centers participate in both and 40 of these 70 agreed to participate in this linkage project. The manual adjudication process and the refinement of the matrices resulted in an increase in the sensitivity of the matrices from 93% to 100% and an increase in the specificity of the matrices from 94% to 98%.

CONCLUSION

Matrices were created to facilitate the automated identification of patients potentially eligible for the five active CHSS studies using the STS-CHSD. These matrices have a sensitivity of 100% and a specificity of 98%. In addition to facilitating identification of patients potentially eligible for enrollment in CHSS studies, these matrices will allow (1) estimation of the denominator of patients potentially eligible for CHSS studies and (2) comparison of eligible and enrolled patients to potentially eligible and not enrolled patients to assess the generalizability of CHSS studies.