Pulmonary Versus Systemic Outflow Obstruction in Functionally Univentricular Hearts with Isomerism: An Observation.

Our objective was to review our experience with isomerism associated with univentricular hearts and evaluate the prevalence of pulmonary versus systemic outflow obstruction. We identified those prenatally or postnatally diagnosed, between September 2004 and October 2021, with right and left isomerism and a functionally univentricular heart. We identified 62, 51 prenatally and 11 postnatally. Of the 62, 61 had prenatal care for an 84% (51/61) prenatal detection rate. Of the 62, 36 (58%) had right isomerism. Of the 51 prenatally diagnosed, 36 were live-born, 13 had fetal demise, and two underwent elective termination. Of the total 62, 43 had pulmonary outflow obstruction, 14 had systemic outflow obstruction, three had no outflow obstruction, and two had a common arterial trunk. However, between September 2004 and December 2019, 41 of 52 (79%) had pulmonary outflow obstruction, and between January 2000 and October 2021, 2 of 10 (20%) had pulmonary outflow obstruction (p = 001). We noted a statistically significant temporal change in the prevalence of pulmonary versus systemic outflow obstruction in those with isomeric situs and a functionally univentricular heart. Further, prenatal diagnosis exceeded 80% in the general population of Nevada.

Hepatic fibrosis gender differences in extracardiac Fontan patients.

OBJECTIVE: We investigated possible gender differences for hepatic fibrosis in extracardiac-Fontan patients. METHODS: We identified extracardiac Fontan, performed between 2000 and 2016, who underwent cardiac catheterizations with transvenous hepatic biopsies between April 2012 and June 2022. We divided the patients by gender for analysis. RESULTS: We identified 116 patients who underwent 145 transvenous biopsies, with 29 patients undergoing 2 biopsies at an average interval of 5 ± 1 years. We divided the 145 biopsies into two groups: 1) 98/145 (68%) males and 2) 47/145 (32%) females. For the 47 female liver biopsy specimens, the median total fibrosis score was 3 (0-8), and for the 98 male liver biopsy specimens, the median total fibrosis score was 2 (0-6), p = .007. The average age at surgery for females was 3 ± 1 years and for males 3 ± 1 years, p = .99. Average Fontan duration at biopsy for females was 11 ± 5 years and for males, 10 ± 4 years, p = .23. No other demographic, anatomic, echocardiographic, laboratory, or hemodynamic findings demonstrated statistically significant gender differences. CONCLUSIONS: Females had statistically significantly higher median total fibrosis scores than males for the similar average age at extracardiac Fontan and average Fontan duration.

Complex neonatal congenital heart surgery in Nevada.

OBJECTIVE: We reviewed our center's surgical mortality rates for those who underwent a Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) category 4 or 5 neonatal cardiovascular surgery. METHODS: We identified all patients who underwent a STAT category 4 or 5 neonatal index cardiovascular surgical procedure between July 2015 and July 2021. RESULTS: We identified 239 patients. We divided them into two groups: (1) 42 (17.6%) ≤2.5 kg, and (2) 197 (82.4%) were >2.5 kg at the time of neonatal surgery. Of those ≤2.5 kg, 18/42 (42.9%) had syndromes or associated noncardiac malformations versus 34/197 (17.3%) of those >2.5 kg, p = .0093. Thirty-day discharge mortality for those ≤2.5 kg was 3/42 (7.1%) versus l0/197 (5.1%) for those >2.5 kg, p = .83. CONCLUSIONS: Weight at the time of surgery, presence of syndromes, and associated noncardiac malformations did not affect mortality in those undergoing complex neonatal STAT 4 or 5 category cardiovascular surgery.

Prenatal diagnosis of hypoplastic aortic arch without intracardiac malformations: The nevada experience.

OBJECTIVE: We reviewed our center's experience with neonatal and infant hypoplastic aortic arch, unassociated with intracardiac malformations, and investigated changes in prenatal detection rates over time for those requiring therapeutic procedures. METHODS: We identified all prenatal diagnoses of hypoplastic aortic arch with situs solitus, unassociated with intracardiac malformations, made in Nevada between May 2017 and April 2022. In addition, we identified all those 0-180 days old, with prenatal care, that underwent a surgical or interventional cardiac catheterization aortic arch procedure, whether prenatally or postnatally diagnosed. We excluded those with ventricular septal defects, functionally univentricular hearts, interrupted aortic arches, or any associated malformation requiring an additional surgical or interventional procedure ≤6 months old. Additionally, we calculated prenatal detection rates for those undergoing a surgical or interventional catheterization procedure for each of the 5 years. RESULTS: We identified 107 patients prenatally and postnatally. Of the 107 patients, 56 (34 prenatally diagnosed and 22 postnatally diagnosed) underwent an aortic arch procedure, and 51 additionally prenatally diagnosed, live-born infants did not undergo a procedure. Of the 56 procedures, 2 were by interventional catheterization, and 54 underwent a surgical repair. Prenatal detection for those undergoing a procedure statistically significantly increased over the 5 years from 38% to 82%, rho = 0.95 (p = .04). CONCLUSIONS: Currently in Nevada, our prenatal detection rate is >80% in the general population for those between 0 and 6 months old who require a therapeutic procedure for aortic arch obstruction without intracardiac malformations.

Prenatal diagnosis in Nevada for patients undergoing cardiovascular surgery in the first six months.

OBJECTIVE: We reviewed our center's experience with prenatal detection in Nevada's general population for young infants undergoing cardiovascular surgery. METHODS: We identified patients born in Nevada that underwent an initial cardiovascular surgery between 0 and 6 months old with birth dates between August 2012 and July 2021. Additionally, we calculated prenatal congenital cardiovascular malformation detection rates for each of the 9 years. RESULTS: We identified 660 patients. For the 660 patients, 649 (98%) mothers underwent prenatal care, which included at least one anatomical-survey obstetric ultrasound. Of the 649 with prenatal care, 395 (61%) had a prenatal diagnosis overall. However, prenatal diagnosis improved over the 9 years from 44% in 2012 to 79% in 2021 (correlation coefficient of 0.93, p = .00024). CONCLUSIONS: Our results demonstrated a progressive rise in prenatal detection rates for young infants undergoing cardiovascular surgery in Nevada.

Common arterial trunk in the era of high prenatal detection rates: Results of neonatal palliation and primary repair.

OBJECTIVE: We reviewed our center's experience with common arterial trunk. METHODS: We included those with common arterial trunk in Nevada with estimated delivery dates or birth dates between June 2006 and May 2021. We excluded patients with functionally univentricular hearts. RESULTS: We identified a total of 39: 32 prenatally and 7 postnatally. Of the 32 prenatally detected, 2 had elective termination, 2 had fetal demise, and 28 were live-born. Of the 7 postnatally diagnosed, 6 had prenatal care without a fetal echocardiogram, and 1 had no prenatal care. Overall, live-born prenatal detection was 28/34 (82%). Prenatal detection for 2006-2009 was 2/6 (33%) and for 2010-2021 was 26/28 (93%) p = .049. Of the 35 live-born infants, 1 died preoperatively, and 34 underwent neonatal surgery. Of the 34, 8 had palliation (birth weight 1.9±0.7 kg, range 0.8-2.6 kg), and 26 had a primary repair (birth weight 3.0±0.3 kg, range 2.6-4.0 kg) p = .0004. For all 34 neonatal surgical procedures, there were 2 (5.9%) deaths; however, there were no subsequent surgical or interventional catheterization mortalities. CONCLUSIONS: In Nevada, current state-wide, general population prenatal detection of the common arterial trunk was more than 90%. By employing a combination of neonatal palliation and primary repair, surgical mortality was less than 6% in a cohort that included those with birth weights less than 2.5 kg, truncal valve surgery, and interrupted aortic arches.

Isolated vascular rings in the era of high prenatal detection rates: Demographics, diagnosis, risk factors, and outcome.

OBJECTIVE: We reviewed our center's isolated vascular ring data. METHODS: Inclusion criteria were patients born in Nevada between June 2015 and July 2020 with situs solitus, levocardia, atrioventricular and ventriculoarterial concordance, and no significant intracardiac malformations. RESULTS: We identified 95 patients. Of the 95, 56 (59%) were female (p = .033). For the study period, there were approximately 180,000 live births, for a prevalence of 5.3 isolated vascular rings per 10,000 live births. Of the 95, 78 (82%) were prenatally diagnosed. Of the 95, 63 (66%) were products of high-risk pregnancies (p = .0001). Additionally, we found advanced maternal age was an isolated vascular ring risk factor (relative risk ratio, 2.7; 95% confidence interval, 1.8, 4.1; p < .00001). CONCLUSIONS: Isolated vascular rings are relatively common cardiovascular malformations and more common in females. High prenatal detection rates are achievable. Further, the majority with isolated vascular rings are products of high-risk pregnancies, and advanced maternal age is a statistically significant occurrence risk factor.

Fontan-associated liver disease and total cavopulmonary anatomical flow effectors.

OBJECTIVE: We investigated a relationship between a composite index comprised of Fontan-circuit anatomical features and hepatic fibrosis scores from biopsy. METHODS: We identified living extracardiac Fontan patients, ≥7 years old and ≥5 but <20 years postoperative, that underwent cardiac catheterization and transvenous liver biopsy between March 2012 and September 2020. We divided patients into anatomical groups and applied a risk score to each patient. We compared average anatomical risk scores with average hepatic total fibrosis scores by group. RESULTS: We identified 111 patients that met inclusion criteria. After excluding four patients, we assigned 107 to one of 12 anatomical variant groups (n ≥ 3). For the 107, the average age at liver biopsy was 14 ± 6 years old. Of the 107, 105 (98%) were New York Heart Association Class 1. We found average anatomical risk scores by group correlated with average total fibrosis scores by group (R = 0.8; p = .005). An average Fontan duration to biopsy of 10 ± 1 years was similar for all 12 anatomical groups. We found no other clinical variables, laboratory, or hemodynamic values that trended with anatomical risk scores or hepatic total fibrosis scores. CONCLUSIONS: In a cohort of relatively young, stable extracardiac Fontan patients, average composite anatomical risk scores strongly correlated with average hepatic total fibrosis scores by anatomical group. These findings suggest that some anatomical variants in extracardiac Fontan patients are associated with higher Fontan-associated liver disease (FALD)-related hepatic total fibrosis scores than others, despite similar Fontan durations.

The Rate of Hepatic Fibrosis Progression in Patients Post-Fontan.

This investigation analyzed the rate of hepatic fibrosis progression in post-Fontan patients that underwent hepatic biopsy. The study cohort comprised post-Fontan patients that underwent cardiac catheterization and transvenous liver biopsy between March 2012 and September 2019. We identified 126 patients that met inclusion criteria. Of the 126, 27 (21%) had a lateral tunnel Fontan, and 99 (79%) had an extracardiac Fontan. For the 27 lateral tunnel Fontan patients, age at Fontan was 4 ± 2 years, and for the 99 extracardiac Fontan patients age at Fontan was 4 ± 2 years (p = 0.98). For the 27 lateral tunnel Fontan patients, the average total fibrosis score was 3.0 ± 1.5; and for the 99 extracardiac Fontan patients, the average total fibrosis was 2.7 ± 1.7 (p = 0.48). For the lateral tunnel Fontan patients, the average Fontan duration was 20 ± 6 years; and for the 99 extracardiac Fontan patients, the average Fontan duration was 11 ± 5 years (p < 0.001). For the 27 lateral tunnel Fontan patients, the average rate of fibrosis progression was 0.16 ± 0.10 total fibrosis score/year; and for the 99 extracardiac Fontan patients, the average rate of fibrosis progression was 0.30 ± 0.23 total fibrosis score/year (p < 0.001). In conclusion, our findings suggest that those with extracardiac Fontans have a faster rate of hepatic fibrosis progression than those with lateral tunnel Fontans. More extensive or multi-institutional studies will be needed to confirm these findings and define the clinical significance of discrepant rates of hepatic fibrosis in post-Fontan patients.

Fontan venovenous collaterals and hepatic fibrosis.

OBJECTIVE: We hypothesized that a relationship might exist between angiographically demonstrable, post-Fontan venovenous collaterals, and hepatic fibrosis. METHODS: We analyzed data from post-Fontan patients that underwent cardiac catheterization and transvenous-hepatic biopsy procedures between March 2012 and March 2020. From innominate vein angiography, we determined those that either had or lacked venovenous collaterals. Additionally, we examined data from post-Fontan patients that underwent hepatic ultrasound, shear-wave elastography between January 2017 and March 2020. RESULTS: We identified 164 patients that met inclusion criteria. Of the 164, 101 (62%) had venovenous collaterals. Of the 101 with collaterals, average total fibrosis score (TFS) was 3.2 and the average rate of fibrosis progression was 0.28 vs an average TFS of 2.1 and an average fibrosis progression rate of 0.22 for those without collaterals (P = .00001 and P = .01, respectively). Of the 101 with collaterals, oxygen saturation was 91% ± 4% vs 93% ± 3% (P = .048) without collaterals. Of the 164, 86 (52%) underwent ultrasound shear-wave elastography. Of the 86 patients undergoing elastography, 50 (58%) were performed in those with collaterals, and 36 (42%) in those without collaterals. For the 50 with collaterals, average elastography values were 13.3 vs 11.2 kPa for the 36 without collaterals (P = .006). We found no statistically significant differences for age at biopsy, Fontan duration, Fontan-type, type of functional univentricle, laboratory, clinical, or hemodynamic values between those with or without collaterals. CONCLUSIONS: The presence of angiographically demonstrated venovenous collaterals was associated with statistically, significantly more advanced liver fibrosis than those without collaterals.

Analysis of Screening Electrocardiogram for the Subcutaneous Defibrillator in Adults with Congenital Heart Disease.

Candidates for the subcutaneous implantable cardioverter-defibrillator (S-ICD) are screened using an electrocardiogram (S-ECG) tool to measure appropriate detection. We sought to define the S-ICD candidacy of congenital heart disease patients using the S-ECG tool. We also analyzed the reliability of the (S-ECG) tool between measurers in this population. Patients above the age of 12 and with a diagnosis associated with either a higher incidence of cardiac arrest or vascular access challenges were asked to undergo screening. S-ECGs were then analyzed by a pediatric electrophysiologist, an S-ICD device engineer, and an S-ICD clinical representative for candidacy. Results were compared for interobserver variability and S-ECGs were analyzed by t test to determine variables that differ among passing and failing leads. Thirty-one patients underwent screening. Two of the 31 (6.5%) patients failed S-ICD screening. Analysis of the screening leads demonstrated the highest passing rates using lead III at a 5 mm/mV amplitude setting with 71 and 62% pass rate in the supine and standing positions, respectively. Interobserver analysis correlated well among the three measurers. There was a higher amplitude difference between QRS and T waves among passing versus failing S-ECG. Congenital heart disease patients have acceptable passage rates utilizing the S-ECG algorithm. Interobserver measurements were well correlated and these data suggest that the proximal coil to device (lead III) vector would be best utilized in this patient population. A larger difference between QRS and T wave amplitudes was associated with a higher S-ECG passing rate.

Normal Sinus Rhythm-Sinus Bradycardia is Common in Young Children Post-extracardiac Fontan.

We hypothesized that normal sinus rhythm-sinus bradycardia is common in young children following extracardiac Fontan. After excluding patients with sinus pauses, junctional rhythm, tachy-brady syndrome, frequent ectopics, or ectopic atrial rhythm, we found an ambulatory 24-h Holter monitor average heart rate of 78 ± 12 beats per minute (bpm) in 33 post-extracardiac Fontan children with a median age of 6 years (5-10). A 24-h average heart rate of 78 ± 12 bpm is statistically significantly lower than a 24-h average heart rate value of 90 ± 10 bpm derived from a similarly aged control population (p < 0.01). We conclude that after excluding those with significant arrhythmias, normal sinus rhythm-sinus bradycardia is common in children post-extracardiac Fontan.

MELD-XI Scores Correlate with Post-Fontan Hepatic Biopsy Fibrosis Scores.

We tested the hypothesis that MELD-XI values correlated with hepatic total fibrosis scores obtained in 70 predominately stable, post-Fontan patients that underwent elective cardiac catheterization. We found a statistically significant correlation between MELD-XI values and total fibrosis scores (p = 0.003). Thus, serial MELD-XI values may be an additional useful clinical parameter for follow-up care in post-Fontan patients.

An Observation from Liver Biopsies Two Decades Post-Fontan.

This brief report describes an observation from liver biopsy results in nonfailing Fontan patients, currently in their second postoperative decade. In three patients, with either atriopulmonary or atrioventricular connections and functional left ventricles, we found no portal fibrosis. In contrast, we found portal fibrosis in three clinically similar, nonfailing Fontan patients with lateral tunnel connections and functional left ventricles. We recognize the results may be secondary to chance; nevertheless, we speculate about possible relevancy.

Fontan Outcomes and Pulmonary Blood Flow at Birth.

We previously noted, in a small group of post-Fontan patients, a possible association between hepatic fibrosis scores and the status of pulmonary blood flow at birth. To further explore this observation, we examined data from all Fontan patients seen in our center from July 2010 to March 2015. We identified 200 patients for analysis. Of the 200 patients, 56 underwent transvenous-hepatic biopsy. Of the 200 patients, 13 (6.5%) had protein-losing enteropathy. We divided both the 56 biopsy patients and the entire cohort of 200 patients into 4 groups: (1) unobstructed pulmonary blood flow at birth with functional left ventricles, (2) unobstructed pulmonary blood flow at birth with functional right ventricles, (3) obstructed pulmonary blood flow at birth with functional left ventricles, and (4) obstructed pulmonary blood flow at birth with functional right ventricles. Analysis of the 56 liver-biopsy patient groups showed median hepatic total-fibrosis scores for the 4 groups of 2 (0-6), 2 (0-8), 3 (2-6), and 4 (1-8), respectively, with statistical significance between groups 4 and 1 (p = 0.031). For the entire cohort of 200 patients, we analyzed the incidence of protein-losing enteropathy for each of the four groups and found protein-losing enteropathy percent occurrences of 0, 2.9, 8.8, and 16.1, respectively, with statistical significance between groups 4 and 2 (p = 0.031) and between groups 4 and 1 (p = 0.025). A history of obstructed pulmonary blood flow at birth, coupled with a functional right ventricle, may predict a poorer long-term Fontan outcome.

Hybrid Palliation for Ductal-Dependent Systemic Circulation.

We reviewed our hybrid palliation experience for 91 neonates, with ductal-dependent systemic circulation, born between August 2007 and October 2015. For analysis, we stratified the 91 patients by a risk factor (RF) score and divided them into three groups: (1) high-risk two-functional ventricles (2V) median RF score of 3 (N = 20); (2) low-risk one-functional ventricle (1V) RF score 0-1 (N = 32); and (3) high-risk 1V RF score ≥2 (N = 39). Midterm survival (median 4 years) by group was: (1) 95 %, (2) 91 %, and (3) 15 %, (p = 0.001). In conclusion, hybrid palliation was associated with excellent midterm results for high-risk 2V and low-risk 1V patients with ductal-dependent systemic circulation. In contrast, high-risk 1V patients had significantly worse outcomes.

Heterotaxy in southern Nevada: prenatal detection and epidemiology.

We retrospectively analyzed a combination of prenatally detected and postnatally diagnosed patients with heterotaxic situs that included those with situs inversus, bilateral left-sidedness, and bilateral right-sidedness for the period between April 2002 and July 2014. We found a statistically higher prevalence in the Hispanic population of Southern Nevada of 2.7/10,000 live births (95 % confidence intervals of 1.7-3.9) versus the non-Hispanic population of 1.6/10,000 live births (95 % confidence intervals of 1.1-2.1), p = 0.04. Additionally, we noted a high prenatal detection rate of 68 % over the 12-year period of time, rising to 100 % over the last 2 years.

Fontan hepatic fibrosis and pulmonary vascular development.

Fontan patients are at risk for hepatic fibrosis; however, risk factors are unclear. We performed a multivariate analysis in a small cohort of 14 patients (7-24 years old, mean 15) with Fontan circulation, undergoing cardiac catheterization and transvenous liver biopsies, all demonstrating fibrosis. We found by stepwise regression analysis that the history of pulmonary atresia was a predictor of higher total hepatic fibrosis scores than a history of unobstructed pulmonary blood flow (p = 0.002). Other variables including age, time from Fontan, hemodynamic measurements, and laboratory values were not predictive of total fibrosis scores at p values <0.05. Hepatic fibrosis scores between those born with pulmonary atresia versus unrestricted pulmonary blood flow may reflect differences in pulmonary circulatory physiology, resulting from differences in pulmonary vascular development.

Moving towards universal prenatal detection of critical congenital heart disease in southern Nevada: a community-wide program.

This study compares the current, prenatal detection rate for critical congenital heart disease in Southern Nevada with the previously reported rate, after developing and expanding a comprehensive, community-wide fetal cardiology program. For the current-period analysis, we inquired our database and electronic health records for patients born in Clark County, Nevada, with critical congenital heart disease between May 2012 and April 2014, and we compared the results with the previous period between May 2003 and April 2006. The major components of the community-wide program include fetal congenital heart disease screening via general obstetric ultrasound studies performed in obstetrician's offices, radiology imaging centers, or maternal-fetal medicine specialty practices; subsequent referral for comprehensive fetal echocardiography performed in maternal-fetal medicine offices under the on-site supervision by fetal cardiologists; and recurring community educational programs teaching the 5-axial plane, fetal echocardiographic screening protocol to general obstetric sonographers and instructing perinatal sonographers in advanced imaging topics. For the current period, the prenatal detection rate for critical congenital heart disease in Southern Nevada was 71 versus 36% for the previous period (p < 0.001). The temporal improvement in prenatal detection of critical congenital heart disease may be related to our expanded decentralized, community-wide fetal cardiology program, and our experiences may be applicable to other metropolitan areas.

Transvenous hepatic biopsy in stable Fontan patients undergoing cardiac catheterization.

Liver pathology complicates Fontan palliation. Previous reports established that both hepatic sinusoidal and portal fibrosis occur in patients after Fontan procedures. Past studies predominantly included symptomatic patient cohorts. Thus, the authors of this study aimed to characterize hepatic pathology via transvenous hepatic biopsies in 21 asymptomatic patients at the time of elective cardiac catheterization. Seven of these patients (33 %) were accompanied by an interventional procedure. Hepatic biopsies showed evidence of either sinusoidal or portal fibrosis or both in all but one patient. The findings showed a statistically significant (p = 0.005) moderately strong positive correlation between fibrosis scores and time since Fontan surgery. Additionally, no significant correlation was found between fibrosis scores and inferior vena cava pressure, pulmonary vascular resistance, platelet counts, or serum laboratory testing of hepatic function.