Myocardial bridges in a pediatric population: Outcomes following a standardized approach.

OBJECTIVE: To describe clinical, functional, surgical, and outcomes data in pediatric patients with a myocardial bridge (MB) evaluated and managed following a standardized approach. METHODS: Prospective observational study included patients evaluated in the Coronary Artery Anomalies Program. Anatomy was determined by computed tomography angiography, myocardial perfusion by stress perfusion imaging, and coronary hemodynamic assessment by cardiac catheterization. RESULTS: In total, 39 of 42 patients with a complete evaluation for MB were included (December 2012 to June 2022) at a median age of 14.1 years (interquartile range, 12.2-16.4). Sudden cardiac arrest occurred in 3 of 39 (8%), exertional symptoms in 14 (36%), and no/nonspecific symptoms in 7 (18%) patients. Exercise stress test was abnormal in 3 of 34 (9%), stress perfusion imaging in 8 of 34 (24%), and resting instantaneous wave-free ratio ≤0.89 or diastolic dobutamine fractional flow reserve ≤0.80 in 11 of 21 (52%) patients. As a result, 15 of 39 (38%) patients were determined to have hemodynamically significant MB, 1 of 15 patients started beta-blocker, and 14 of 15 were referred for surgery. Myotomy (n = 11) and coronary bypass (n = 1) were performed successfully, resulting in improved symptoms and stress testing results. One patient required pericardiocentesis postoperatively, and all were discharged without other complications. At median follow-up time of 2.9 (1.8-5.8) years, all (except 2 pending surgery) were doing well without exercise restriction. CONCLUSIONS: Pediatric patients with MB can present with myocardial ischemia and sudden cardiac arrest. Provocative stress test and intracoronary hemodynamic tests helped risk-stratify symptomatic patients with MB and concern for ischemia. Surgical repair was safe and effective in mitigating exertional symptoms and stress test results, allowing patients to return to exercise without restriction.

Continuous-Flow Ventricular Assist Device Support in Adult Congenital Heart Disease: A 15-Year, Multicenter Experience of Temporary and Durable Support.

Heart failure (HF) is common in adult congenital heart disease (ACHD) patients; however, use of continuous-flow ventricular assist devices (CF-VADs) remains rare. We reviewed outcomes of patients with congenital heart disease greater than or equal to 18 years of age at the time of CF-VAD implant at the affiliated pediatric and adult institutions between 2006 and 2020. In total, 18 ACHD patients (15 with great anatomical complexity) received 21 CF-VADs. Six patients (median age 34 years) received seven percutaneous CF-VADs with a median duration of support of 20 days (3-44 days) with all patients survived to hospital discharge and two patients were bridged to durable CF-VADs. Fourteen patients (median age 38 years) received durable CF-VADs. Thirteen patients (93%) survived to hospital discharge and the median duration of support was 25.8 months (6.4-52.1 months). Estimated survival on durable CF-VAD at 1, 3, and 5 years was 84%, 72%, and 36%, respectively. Three patients were successfully bridged to transplantation. Device-related complications include cerebrovascular accident (n = 5), driveline infection (n = 3), device infection requiring chronic antibiotic therapy (n = 4), gastrointestinal bleeding (n = 6), and presumed pump thrombosis (n = 5). These results show percutaneous and durable CF-VADs can support ACHD patients with advanced HF.

Lesion-specific mortality due to congenital heart disease in U.S. adults from 1999 to 2017.

BACKGROUND: Adults with congenital heart disease (ACHD) comprise an increasing proportion of individuals living with CHD in the United States (US) although little is known regarding lesion or age-specific mortality in the modern era. Our study aimed to describe current era ACHD mortality rates by age and CHD lesion and provide temporal mortality rate trends for the last two decades. METHODS: We conducted a 19-year analysis (1999-2017) of publicly available, de-identified Multiple Cause of Death data compiled and produced by the National Center for Health Statistics. Age and lesion-specific mortality rates were calculated using joinpoint regression. RESULTS: ACHD mortality rates decreased by an average of 2%-4% per year for all adults. CHD lesions resulting in the highest ACHD-related mortality varied by age. Unlike the other lesions, mortality attributed to single ventricle physiology failed to improve in early adulthood (average of 1.6% increase per year). In decedents age 65 years or older, simpler forms of CHD like shunt lesions became more prominent contributors, accounting for 46% of deaths. CONCLUSION: Rates of mortality due to ACHD have declined significantly for adults with CHD, however, continued mortality due to single ventricle physiology remains an area requiring improved strategies to increase survival.

Accuracy of risk models used for public reporting of heart transplant center performance.

BACKGROUND: Heart transplant programs and regulatory entities require highly accurate performance metrics to support internal quality improvement activities and national oversight of transplant programs, respectively. We assessed the accuracy of publicly reported performance measures. METHODS: We used the United Network for Organ Sharing registry to study patients who underwent heart transplantation between January 1, 2016 and June 30, 2018. We used tests of calibration to compare the observed rate of 1-year graft failure to the expected risk of 1-year graft failure, which was calculated for each recipient using the July 2019 method published by the Scientific Registry of Transplant Recipients (SRTR). The primary study outcome was the joint test of calibration, which accounts for both the total number of events predicted (calibration-in-the-large) and dispersion of risk predictions (calibration slope). RESULTS: 6,528 heart transplants were analyzed. The primary test of calibration failed (p <0.0001), indicating poor accuracy of the SRTR model. The calibration-in-the-large statistic (0.63, 95% confidence interval [CI] 0.58-0.68, p < 0.0001) demonstrated overestimation of event rates while the calibration slope statistic (0.56, 95% CI 0.49-0.62, p <0.0001) indicated over-dispersion of event rates. Pre-specified subgroup analyses demonstrated poor calibration for all subgroups (each p <0.01). After recalibration, program-level observed/expected ratios increased by a median of 0.14 (p <0.0001). CONCLUSIONS: Risk models employed for publicly-reported graft survival at U.S. heart transplant centers lack accuracy in general and in all subgroups tested. The use of disease-specific models may improve the accuracy of program performance metrics.

Stroke in patients with secundum atrial septal defect and sequelae after transcatheter closure.

OBJECTIVE: To evaluate the frequency of and risk factors for stroke as a presenting feature in adult patients with secundum atrial septal defect (ASD); rates of post-closure atrial fibrillation (AF) and stroke were also assessed. METHODS: We retrospectively reviewed adult patients who presented with an ASD between 2002 and 2018, excluding those with known atrial arrhythmias. Risk factors for stroke were identified using multivariable logistic regression. Post-closure stroke was evaluated using survival analysis stratified by the presence of post-procedure AF. RESULTS: Of 346 patients with ASD (median age 44 years), 34 (10%) presented with a history of stroke. Independent risk factors included elevated body mass index over 25 (OR: 18.2; 95% CI: 4.0 to 82.2; p<0.001), smoking (OR: 9.5; 95% CI: 3.8 to 23.9; p<0.001) and a prominent Eustachian valve (OR: 9.2; 95% CI: 3.4 to 25.2; p<0.001). A scoring system based on these three parameters provided robust stroke risk stratification. During a median follow-up of 12 months after closure, 12 patients (4%) experienced AF and 4 patients (1%) had a new stroke. AF was highly associated with development of stroke post-closure (p<0.001). CONCLUSIONS: In this study population, the incidence of stroke prior to ASD closure among patients without atrial arrhythmias was 10%. Risk factors included obesity, smoking and prominent Eustachian valve anatomy. Lifestyle changes should be recommended for at-risk patients, and it may be reasonable to consider ASD closure in the absence of haemodynamic indications in patients at increased risk of stroke.

Long-term adult congenital heart disease survival after heart transplantation: A restricted mean survival time analysis.

BACKGROUND: Adult Congenital Heart Disease (ACHD) heart transplant recipients may have lower post-transplant survival resulting from higher peri-operative mortality than non-ACHD patients. However, the late risk of mortality appears lower in ACHD recipients. This study seeks to establish whether long-term heart transplant survival is reduced among ACHD recipients relative to non-ACHD recipients. METHODS: Adult patients who received a heart transplant between January, 2000 and December, 2019 in the United Network for Organ Sharing database were stratified by the presence of ACHD. Propensity-matched cohorts (1:4) were created to adjust for differences between groups. Graft survival at time points from 1 to 18 years was compared between groups using restricted mean survival time (RMST) analysis. RESULTS: The matched cohort included 1,139 ACHD and 4,293 non-ACHD patients. Median age was 35 years and 61% were male. Average survival time at 1 year was 0.85 years for ACHD patients and 0.93 years for non-ACHD patients (average difference: -0.08 years, 95% Confidence Interval [CI] -0.10 to -0.06, p < 0.001), reflecting higher immediate post-transplant mortality. Average survival time at 18 years was not clinically or statistically different: 11.14 years for ACHD patients and 11.40 years for non-ACHD patients (average difference: -0.26 years, 95% CI: -0.85 to + 0.32 years, p = 0.38). CONCLUSIONS: Despite increased medium-term mortality among ACHD patients after heart transplant, differences in long-term survival are minimal. Allocation of hearts to ACHD patients results in acceptable utility of donor hearts.

Risk Factors Associated With Bleeding in Children With Cardiac Disease Receiving Extracorporeal Membrane Oxygenation: A Multi-Center Data Linkage Analysis.

Background: Bleeding is a common complication of extracorporeal membrane oxygenation (ECMO) for pediatric cardiac patients. We aimed to identify anticoagulation practices, cardiac diagnoses, and surgical variables associated with bleeding during pediatric cardiac ECMO by combining two established databases, the Collaborative Pediatric Critical Care Research Network (CPCCRN) Bleeding and Thrombosis in ECMO (BATE) and the Extracorporeal Life Support Organization (ELSO) Registry. Methods: All children (<19 years) with a primary cardiac diagnosis managed on ECMO included in BATE from six centers were analyzed. ELSO Registry criteria for bleeding events included pulmonary or intracranial bleeding, or red blood cell transfusion >80 ml/kg on any ECMO day. Bleeding odds were assessed on ECMO Day 1 and from ECMO Day 2 onwards with multivariable logistic regression. Results: There were 187 children with 114 (61%) bleeding events in the study cohort. Biventricular congenital heart disease (94/187, 50%) and cardiac medical diagnoses (75/187, 40%) were most common, and 48 (26%) patients were cannulated directly from cardiopulmonary bypass (CPB). Bleeding events were not associated with achieving pre-specified therapeutic ranges of activated clotting time (ACT) or platelet levels. In multivariable analysis, elevated INR and fibrinogen were associated with bleeding events (OR 1.1, CI 1.0-1.3, p = 0.02; OR 0.77, CI 0.6-0.9, p = 0.004). Bleeding events were also associated with clinical site (OR 4.8, CI 2.0-11.1, p < 0.001) and central cannulation (OR 1.75, CI 1.0-3.1, p = 0.05) but not with cardiac diagnosis, surgical complexity, or cannulation from CPB. Bleeding odds on ECMO day 1 were increased in patients with central cannulation (OR 2.82, 95% CI 1.15-7.08, p = 0.023) and those cannulated directly from CPB (OR 3.32, 95% CI 1.02-11.61, p = 0.047). Conclusions: Bleeding events in children with cardiac diagnoses supported on ECMO were associated with central cannulation strategy and coagulopathy, but were not modulated by achieving pre-specified therapeutic ranges of monitoring assays.

Outcomes of Adults with Congenital Heart Disease Supported with Extracorporeal Life Support After Cardiac Surgery.

Patients with adult congenital heart disease (ACHD) who undergo cardiac surgery may require extracorporeal life support (ECLS) for cardiopulmonary support, but outcomes after ECLS support have not been well described. This study aimed to identify risk factors for ECLS mortality in this population. We identified 368 ACHD patients who received ECLS after cardiac surgery between 1994 and 2016 in the Extracorporeal Life Support Organization (ELSO) database, a multicenter international registry of ECLS centers. Risk factors for mortality were assessed using multivariate logistic regression. Overall mortality was 61%. In a multivariate model using precannulation characteristics, Fontan physiology (odds ratio [OR]: 5.7; 95% CI: 1.6-20.0), weight over 100 kg (OR: 2.6; 95% CI: 1.3-5.4), female gender (OR: 1.6; 95% CI: 1.001-2.6), delayed ECLS cannulation (OR: 2.0; 95% CI: 1.2-3.2), and neuromuscular blockade (OR: 1.9; 95% CI: 1.1-3.3) were associated with increased mortality. Adding postcannulation characteristics to the model, renal complications (OR: 3.0; 95% CI: 1.7-5.2), neurologic complications (OR, 4.7; 95% CI: 1.5-15.2), and pulmonary hemorrhage (OR: 6.4; 95% CI: 1.3-33.2) were associated with increased mortality, whereas Fontan physiology was no longer associated, suggesting the association of Fontan physiology with mortality may be mediated by complications. Fontan physiology was also a risk factor for neurologic complications (OR: 8.2; 95% CI: 3.3-20.9). Given the rapid increase in ECLS use, understanding risk factors for ACHD patients receiving ECLS after cardiac surgery will aid clinicians in decision-making and preoperative planning.

Utility of biomarkers in adult Fontan patients with decompensated heart failure.

BACKGROUND: The incidence of heart failure is increasing within the Fontan population. The use of serological markers, including B-type natriuretic peptide, has been limited in this patient population. METHODS: This was a single-centre retrospective study of Fontan patients in acute decompensated heart failure. Fontan patients underwent a 1:2 match with non-Fontan patients for each heart failure hospitalisation for comparative analysis. A univariate logistic regression model was used to assess associations between laboratory and echocardiographic markers and a prolonged length of stay of 7 days or greater. RESULTS: B-type natriuretic peptide levels were significantly lower in Fontan patients admitted for heart failure than that in non-Fontan patients [390.9 (±378.7) pg/ml versus 1245.6 (±1160.7) pg/ml, respectively, p < 0.0001] and were higher in Fontan patients with systemic ventricular systolic or diastolic dysfunction than that in Fontan patients with normal systemic ventricular function [833.6 (±1547.2) pg/ml versus 138.6 (±134.0) pg/ml, p = 0.017]. The change from the last known outpatient value was smaller in Fontan patients in comparison with non-Fontan patients [65.7 (±185.7) pg/ml versus 1638.0 (±1444.7) pg/ml, respectively, p < 0.0001]. Low haemoglobin and high blood urea nitrogen levels were associated with a prolonged length of stay. CONCLUSION: B-type natriuretic peptide levels do not accurately reflect decompensated heart failure in Fontan patients when compared to non-Fontan heart failure patients and should, therefore, be used with caution in this patient population.

What Every Cardiologist Should Know About the 2018 Updated Adult Congenital Cardiology Guidelines.

PURPOSE OF REVIEW: Review the recently updated guidelines for the management of patients with adult congenital heart disease (ACHD) with a focus on the changes between these guidelines and the prior guidelines. RECENT FINDINGS: The 2018 guidelines for the management of patients with ACHD focused on utilizing the available data and limiting the number recommendations based only on expert opinion. These guidelines implement a new anatomic and physiological classification scheme to guide management of patients, which takes into account both the underlying anatomy as well as residual cardiac disease and symptoms. Given a lack of robust outcomes data for many types of CHD, the new guidelines provide fewer total recommendations than the prior version, emphasizing the data that is available and drawing attention to the need for additional data. The 2018 guidelines provide the field with a comprehensive update in the management of ACHD patients with an emphasis on the available data.

Improved Outcomes of Heart Transplantation in Adults With Congenital Heart Disease Receiving Regionalized Care.

BACKGROUND: The number of adult congenital heart disease (CHD) patients undergoing heart transplantation is increasing rapidly. CHD patients have higher surgical risk at transplantation. High-volume adult CHD transplant centers may have better transplant outcomes. OBJECTIVES: This study aimed to evaluate the effect of center CHD transplant volume and expertise on transplant outcomes in CHD patients. METHODS: The authors studied heart transplantations in CHD patients age ≥18 years using the United Network of Organ Sharing (UNOS) database for the primary outcomes of waitlist mortality and post-transplant outcomes at 30 days and 1 year. Transplant centers were assessed by status as the highest CHD transplant volume center in a UNOS region versus all others, presence of Adult Congenital Heart Association accreditation, and adult versus pediatric hospital designation. RESULTS: Between January of 2000 and June of 2018, 1,746 adult CHD patients were listed for transplant; 1,006 (57.6%) of these underwent heart transplantation. After adjusting for age, sex, listing status, and inotrope requirement, waitlist mortality risk was lower at Adult Congenital Heart Association accredited centers (hazard ratio: 0.730; p = 0.020). Post-transplant 30-day mortality was lower at the highest volume CHD transplant center in each UNOS region (hazard ratio: 0.706; p = 0.014). CONCLUSIONS: Designated expertise in CHD care is associated with improved waitlist outcomes for CHD patients listed for transplantation. Post-transplant survival was improved at the highest volume regional center. These findings suggest a possible advantage of regionalization of CHD transplantation.

Predictors of extracorporeal membrane oxygenation support after surgery for adult congenital heart disease in children's hospitals.

OBJECTIVE: Adult congenital heart disease (ACHD) patients who undergo cardiac surgery are at risk for poor outcomes, including extracorporeal membrane oxygenation support (ECMO) and death. Prior studies have demonstrated risk factors for mortality, but have not fully examined risk factors for ECMO or death without ECMO (DWE). We sought to identify risk factors for ECMO and DWE in adults undergoing congenital heart surgery in tertiary care children's hospitals. DESIGN: All adults (≥18 years) undergoing congenital heart surgery in the Pediatric Health Information System (PHIS) database between 2003 and 2014 were included. Patients were classified into three groups: ECMO-free survival, requiring ECMO, and DWE. Univariate analyses were performed, and multinomial logistic regression models were constructed examining ECMO and DWE as independent outcomes. SETTING: Tertiary care children's hospitals. RESULTS: A total of 4665 adult patients underwent ACHD surgery in 39 children's hospitals with 51 (1.1%) patients requiring ECMO and 64 (1.4%) patients experiencing DWE. Of the 51 ECMO patients, 34 (67%) died. Increasing patient age, surgical complexity, diagnosis of single ventricle heart disease, preoperative hospitalization, and the presence of noncardiac complex chronic conditions (CCC) were risk factors for both outcomes. Additionally, low and medium hospital ACHD surgical volume was associated with an increased risk of DWE in comparison with ECMO. CONCLUSIONS: There are overlapping but separate risk factors for ECMO support and DWE among adults undergoing congenital heart surgery in pediatric hospitals.

Effect of Congenital Heart Disease Status on Trends in Pediatric Infective Endocarditis Hospitalizations in the United States Between 2000 and 2012.

The purpose of this study was to create national estimates for the incidence of pediatric infective endocarditis (IE) in the United States and to determine if these changed after the implementation of the 2007 American Heart Association IE guidelines. It also sought to determine the effect of congenital heart disease (CHD) status on outcomes in IE. Hospital discharges with the diagnosis of IE in patients < 18 years old from the Kids' Inpatient Database were identified from the years 2000, 2003, 2006, 2009, and 2012. Discharges were grouped into Pre- and Post-2007 groups to facilitate analysis surrounding the implementation of the guidelines in 2007. Patients were categorized by age, underlying CHD, and etiologic organism. Descriptive comparisons and changes in categorical variables were made between groups. Average annual IE hospitalization rates before and after the 2007 guidelines were 10.8 and 9.3 per 1,000,000 children, respectively. The proportion of IE patients with CHD was stable between time periods, (45% vs. 47%, p = 0.50). Mortality was higher in the Post-2007 time period for CHD patients than non-CHD patients (11.1% vs. 2.4%, respectively; p < 0.001), while there was no difference noted during the Pre-2007 time period (6.5% vs. 6.6%, respectively; p = 0.95). Streptococcus was more common among CHD patients than non-CHD patients (27% vs. 17%), while Staphylococcus was more common among non-CHD patients than CHD patients (34% vs. 24%, p < 0.001). Even though the incidence of IE was stable over time, mortality was higher in CHD patients after the implementation of the 2007 AHA IE prophylaxis guidelines.

Prenatal physiologic findings and postnatal advanced imaging in the management of absent pulmonary valve syndrome with intact ventricular septum.

Absent pulmonary valve syndrome is a congenital heart defect usually associated with tetralogy of Fallot. Rarely, absent pulmonary valve syndrome can occur independently of tetralogy of Fallot and presents with an intact ventricular septum and a patent ductus arteriosus. This case report describes the prenatal diagnosis of absent pulmonary valve syndrome with intact ventricular septum via echocardiogram and the postnatal management of the resulting physiologic effects secondary to this rare congenital heart disease.

Understanding and engineering RNA sequence specificity of PUF proteins.

PUF proteins are RNA-binding proteins named for founding members PUMILIO and fem-3 binding factor (FBF). Together these proteins represent the range of known RNA recognition properties. PUMILIO is a prototypical PUF protein whose RNA sequence specificity is simple, elegant, and predictable. FBF displays differences in RNA recognition that represent divergence from the prototype. Here we review recent studies that examine the engineering of sequence specificity of PUF proteins and its applications as well as studies that increase our understanding of the natural diversity of RNA recognition by this family of proteins.