Ideal chest compression site for cardiopulmonary resuscitation in fontan circulation patients with dextrocardia.

BACKGROUND: We aimed to identify the ideal chest compression site for cardiopulmonary resuscitation (CPR) in patients with a single ventricle with dextrocardia corrected by Fontan surgery. METHODS: The most recent stored chest computed tomography images of all patients with a single ventricle who underwent Fontan surgery were retrospectively analysed. We reported that the ideal chest compression site is the largest part of the compressed single ventricle. To identify the ideal chest compression site, we measured the distance from the midline of the sternum to the point of the maximum sagittal area of the single ventricle as a deviation and calculated the area fraction of the compressed structures. RESULTS: 58 patients (67.2% male) were analysed. The mean right deviation from the midline of the sternum to the ideal compression site was similar to the mean sternum width (32.85 ± 15.61 vs. 31.05 ± 6.75 mm). When chest compression was performed at the ideal site, the area fraction of the single ventricle significantly increased by 7%, which was greater than that of conventional compression (0.15 ± 0.10 vs. 0.22 ± 0.11, P < 0.05). CONCLUSIONS: When performing CPR on a patient with Fontan circulation with dextrocardia, right-sided chest compression may be better than the conventional location.

Effect of liver abnormalities on mortality in Fontan patients: a systematic review and meta-analysis.

BACKGROUND: Fontan-associated liver disease (FALD) is one of the most common complications following Fontan procedure, but the impact of FALD on survival outcomes remains controversial. The aim of this systematic review and meta-analysis was to examine and quantify the influence of liver disease on the survival of Fontan patients. METHODS: The Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines were followed, and relevant human studies published from inception up to 12 August 2022 were searched. Stata (version 17.0) was applied to perform the meta-analysis, using random effects (Mantel-Haenszel) models. The I2 statistic was used to assess the heterogeneity. Subgroup analysis and meta-regression were employed to explore the potential sources of heterogeneity and sensitivity analysis was performed to determine the potential influence of each study on the overall pooled results. RESULTS: A total of 312 records were initially identified and 8 studies involving 2,466 patients were selected for inclusion. Results revealed a significant association between the severity of liver disease following Fontan procedure and mortality, which was confirmed by sensitivity analysis and subgroup analysis assessing post-HT mortality. Meta-regression showed that diagnostic methods for liver disease may be a source of heterogeneity. After removal of the FALD patients identified by international classification of disease codes, heterogeneity was markedly reduced, and the positive association between all-cause mortality and the severity of liver disease became significant. CONCLUSIONS: This meta-analysis showed the severity of liver disease following the Fontan procedure has a significant association with mortality. Lifelong follow-up is necessary and imaging examinations are recommended for routine surveillance of liver disease. Among patients with failing Fontan and advanced liver disease, combined heart-liver transplantation may provide additional survival benefits.

The Fontan Circulation in Pregnancy: Hemodynamic Challenges and Anesthetic Considerations.

Pregnancy in patients with Fontan physiology presents unique challenges due to altered cardiovascular dynamics inherent to both conditions. The Fontan procedure reroutes venous blood directly to the pulmonary arteries, bypassing the heart, and necessitating precise regulation of pulmonary venous resistance and systemic venous pressure to maintain effective cardiac output. The significant cardiovascular adaptations required during pregnancy to meet the metabolic demands of the mother and fetus can overburden the limited preload capacity and venous compliance in Fontan patients, predisposing them to a spectrum of potential complications, including arrhythmias, heart failure, thromboembolism, and obstetric and fetal risks. This review delineates the essential physiological adaptations during pregnancy and the challenges faced by Fontan patients, advocating for a comprehensive care approach involving multidisciplinary collaboration, vigilant monitoring, tailored anesthetic management, and postpartum care. Understanding the complex dynamics between Fontan physiology and pregnancy is crucial for anesthesiologists to develop and execute individualized management strategies to minimize risks and optimize outcomes for this high-risk population.

Spleen shear wave elastography measurements do not correlate with histological grading of liver fibrosis in Fontan physiology: a preliminary investigation.

BACKGROUND: Elevated spleen stiffness may be seen in patients with portal hypertension due to cirrhosis. In patients with Fontan physiology, elevated liver stiffness has been shown to correlate poorly with liver fibrosis. It is unknown whether spleen stiffness may instead serve as a surrogate marker of liver fibrosis in these patients. OBJECTIVE: To compare spleen stiffness determined by shear wave elastography (SWE) with histological findings of an ultrasound-guided liver biopsy in patients who had undergone Fontan palliation as a potential surrogate for Fontan-associated liver disease. MATERIALS AND METHODS: This was an IRB-approved single-center, retrospective study. Patients with Fontan palliation who had undergone both a spleen SWE study and a percutaneous liver biopsy between 2016 and 2020 were included. Biopsy, performed during cardiac catheterization, within 3 months of the SWE was required for inclusion. Using Kruskal-Wallis tests, spleen stiffness was compared with three liver biopsy scoring methods: Ishak, METAVIR, and congestive hepatic fibrosis score (CHFS). When available, Pearson's correlation was also used to compare collagen deposition determined using Sirius Red stain (%SR) with SWE values. A P-value < 0.05 was considered statistically significant. RESULTS: Twenty-two patients (15 males) were included in the study, with a median age of 17 years (IQR is 14.8-20.5 years; age range: 7 years to 30.2 years). The median spleen stiffness was 2.94 m/s (IQR: 2.57-3.61 m/s; range: 1.48-4.27 m/s). The median Fontan pressure was 11 mm Hg (IQR: 10-13.3 mm Hg; range: 7-19 mm Hg) obtained within a median of 10 days (IQR: 1-41 days) of SWE. Splenic stiffness did not correlate with the extent of fibrosis determined by histology (all P > 0.05). There was also no statistically significant correlation between the %SR staining and SWE-determined spleen stiffness (Pearson's correlation of 0.165, P = 0.59, n = 13). CONCLUSIONS: In this preliminary study, SWE spleen stiffness values did not correlate with biopsy-determined scoring of liver fibrosis in patients with Fontan physiology.

Augmented Biphasic Breathing Using Sniff and an Oral Positive Expiratory Pressure Device (Sniff-PEP) in Fontan Patients.

The use of an oral positive expiratory pressure device (oPEP) with sniff breathing (Sniff-PEP) mimics biphasic ventilation. Biphasic ventilation increases pulmonary blood flow and cardiac output in Fontan patients. The aim of this study was to assess the effect of Sniff-PEP on Fontan flow velocities. A single-center, pilot, prospective study was carried out in 15 subjects with Fontan circulation enrolled to use the oPEP device for 1 month. Subjects were instructed on Sniff-PEP and to use the device for 10-15 min 3-4 times a day. Measurements of flow velocity and cardiac output were measured via echocardiogram and quality of life assessments were performed at baseline and 4-6 weeks later. The mean age at enrollment was 19.9 ± 8.7 years (age range of 10-37 years). 7 patients (47%) had dominant left ventricle and 8 (53%) had an open fenestration. There was a statistically significant increase in flow velocities in the hepatic vein from 27.5 ± 7.6 to 35.1 ± 11.3 cm/s (p = 0.003), left pulmonary artery from 51.6 ± 16.6 to 57.6 ± 21.1 cm/s (p = 0.01), and right pulmonary artery from 43.1 ± 14.2 to 45.8 ± 17.2 cm/s (p = 0.04). With chronic use, the mean fenestration gradient slightly decreased from 4.5 ± 1.6 to 4.1 ± 1.9 mmHg but the difference was not statistically significant (p = 0.14). oPEP device therapy increased flow velocity in several areas in the Fontan circulation with acute use. Further studies are needed to assess the effects long term.Clinical Trial Registration: URL: https://clinicaltrials.gov . Unique identifier: NCT03251742.

Real-World Use and Outcomes of Apixaban for Early Post-Surgical Fontan Thromboprophylaxis.

Patients with Fontan physiology are at heightened risk of thrombosis related to passive venous return leading to increased stasis, as well as acquired thrombophilia from congestive hepatopathy. Variability exists for post-Fontan thromboprophylaxis, with no consensus on best practices. Direct oral anticoagulants offer advantages over conventional anticoagulants including fewer drug-drug interactions, no dietary restrictions, and less frequent monitoring. Herein, we report our single center experience utilizing apixaban thromboprophylaxis in children post-Fontan procedure. Single center, retrospective, cohort study evaluating apixaban thromboprophylaxis dosing strategies, efficacy, and safety in children admitted post-Fontan procedure at Boston Children's Hospital. Between September 2019 and December 2023, 62 children, median age 3.2 years (2.1-10.5 years), weight 13.9 kg (9.5-56.3 kg) received apixaban at a median of 93 days post-Fontan (7-1421 days). Over a total of 93 days of apixaban exposure, there was 1 treatment-related thrombosis event (0.07 per 1000 person-days on apixaban) and 3 combined treatment-related clinically relevant non-major (CRNM) and major bleeding events (0.22 per 1000 person-days on apixaban). Apixaban for post-Fontan thromboprophylaxis was feasible with low rates of bleeding and thrombosis.

Assessment of liver fibrosis using a 3-dimensional high-resolution late gadolinium enhancement sequence in children and adolescents with Fontan circulation.

OBJECTIVES: To assess abnormal liver enhancement on 15-20 min delayed 3D high-resolution late gadolinium enhancement (3D HR LGE) sequence in patients with Fontan circulation. METHODS: Retrospective study of pediatric Fontan patients (< 18 years old) with combined cardiac-liver MRI from January 2018 to August 2021. Abnormal hepatic enhancement was graded (0-3) for each lobe, summed for a total liver enhancement score (0-6), and compared to repaired tetralogy of Fallot (rTOF) patients. Correlations with other hepatic imaging biomarkers were performed. Temporal relationships of enhancement compared to traditional early portal venous and 5-7-min delayed phase liver imaging were analyzed. RESULTS: The Fontan group (n = 35, 13 ± 3.4 years old, median time from Fontan 10 (9-12) years) had 23/35 (66%) with delayed 3D HR LGE total liver enhancement score > 0 (range 0-5), with greater involvement of the right lobe (1 (0-1) vs 0 (0-1), p < 0.01). The rTOF group (n = 35, 14 ± 2.6 years old) had no abnormal enhancement. In the Fontan group, total liver enhancement was 3 (2-4) in the early portal venous phase, lower at 1 (1-2) in the 5-7-min delayed phase (p < 0.01), and lowest at 1 (0-2) in the 15-20-min delayed phase (p = 0.03). 3D HR LGE enhancement correlated inversely with portal vein flow (rs = - 0.42, p = 0.01) and positively with left lobe stiffness (rs = 0.51, p < 0.01). The enhancement score decreased in 13/35 (37%) between the 5-7- and 15-20-min delayed phases. CONCLUSIONS: Liver fibrosis can be assessed on 3D HR LGE sequences in patients with Fontan circulation, correlates with other imaging biomarkers of Fontan liver disease, and may add information for hepatic surveillance in this population. KEY POINTS: • Abnormal liver enhancement on 3D HR LGE sequences in Fontan patients likely represents liver fibrosis and is seen in up to 66% of children and adolescents with variable distribution and severity. • The degree of 3D HR LGE liver enhancement correlates with decreased portal vein flow and increased left hepatic lobe stiffness.

Body composition in patients with Fontan physiology: a systematic review.

Fontan circulation is a highly abnormal circulatory state that may affect various organ systems. The effect on body composition is an important factor to assess the condition of the patient. This systematic review assesses body composition and possibly related adverse outcomes in patients with a Fontan circulation, to provide an overview of current insights. Studies evaluating body composition by compartment (either fat mass or lean/muscle mass) in Fontan patients published up to April 2023 were included in this systematic review. Of 1392 potential studies, 18 studies met the inclusion criteria. In total, body composition measurements of 774 Fontan patients were included. Body composition was measured using dual-energy X-ray absorptiometry (DXA) (n = 12), bioelectrical impedance analysis (BIA) (n = 5), computer tomography (CT) (n = 1), or magnetic resonance imaging (MRI) (n = 1). All studies reported a normal body mass index (BMI) in Fontan patients, compared to controls. Five out of nine studies reported significantly higher body fat values, and twelve out of fifteen studies reported significantly lower muscle or lean mass values in the Fontan population compared to the healthy population. Unfavorable body composition in Fontan patients was associated with decreased exercise capacity, worse cardiac function, and adverse outcomes including hospital admissions and death.   Conclusions: Despite having a normal BMI, Fontan patients have an increased fat mass and decreased muscle mass or lean mass compared to the healthy population. This unfavorable body composition was associated with various adverse outcomes, including a decreased exercise capacity and worse cardiac function. What is Known: • Patients with a Fontan circulation have a decreased exercise capacity compared to healthy peers, an unfavorable body composition might be a contributor to their impaired exercise capacity. What is New: • Fontan patients are predisposed to an unfavorable body composition, characterized by increased fat mass and decreased muscle mass accompanied by a normal BMI compared to the healthy population. • Among others, unfavorable body composition was associated with decreased exercise capacity, cardiac function, and increased morbidity in patients with a Fontan circulation.

Somatic growth in single ventricle patients: A systematic review and meta-analysis.

AIM: To map somatic growth patterns throughout Fontan palliation and summarise evidence on its key modifiers. METHODS: Databases were searched for relevant articles published from January 2000 to December 2021. Height and weight z scores at each time point (birth, Glenn procedure, Fontan procedure and >5 years after Fontan completion) were pooled using a random effects meta-analysis. A random effects meta-regression model was fitted to model the trend in z scores over time. RESULTS: Nineteen studies fulfilled eligibility criteria, yielding a total of 2006 participants. The z scores for height and weight were markedly reduced from birth to the interstage period, but recovered by about 50% following the Glenn procedure. At >10 years after the Fontan procedure, the z scores for weight seemed to normalise despite persistent lower height, resulting in increased body mass index. The review revealed a number of modifiers of somatic growth, including aggressive nutritional management, timing of Glenn/Fontan, prompt resolution of complications and obesity prevention programmes in adolescence and adulthood. CONCLUSION: This review mapped the somatic growth of single ventricle patients and summarised key modifiers that may be amendable to improvement. These data provide guidance on strategies to further optimise somatic growth in this population and may serve as a benchmark for clinical follow-up.

Utility of the Total Thrombus-Formation Analysis System as a Tool for Evaluating Thrombogenicity and Monitoring Antithrombotic Therapy in Pediatric Fontan Patients.

BACKGROUND: There is no consensus regarding thromboprophylaxis after Fontan procedure, and novel tools to assess thrombogenicity are needed to establish optimal thromboprophylaxis. The Total Thrombus-formation Analysis System (T-TAS) was developed for the quantitative analysis of thrombus formation using microchips with thrombogenic surfaces. This prospective study evaluated the utility of T-TAS in the assessment of thrombogenicity in pediatric Fontan patients. METHODS AND RESULTS: The participants included 20 consecutive Fontan patients who underwent cardiac catheterization and 30 healthy controls. Blood samples collected without and with antithrombotic therapy (aspirin or aspirin and warfarin) were used for T-TAS to compute the area under the curve (AUC) in the atheroma (AR10-AUC30) and platelet (PL18-AUC10) chips. A higher AUC indicates higher thrombogenicity. T-TAS values showed that patients in the Fontan group without antithrombotic therapy had lower thrombogenicity than those in the control group [PL18-AUC10, median (interquartile range) 356 (313-394) vs. 408 (392-424); AR10-AUC30, median (interquartile range) 1270 (1178-1351) vs. 1382 (1338-1421)]. Aspirin and warfarin therapies significantly decreased PL18-AUC10 and AR10-AUC30, respectively, compared with those of patients without antithrombotic therapy (P < 0.001 for each comparison). Subgroup analysis divided by low (< 9 mmHg) or high (≥ 9 mmHg) central venous pressure (CVP) showed that CVP affects the reduction in AR10-AUC30 with antithrombotic therapy. CONCLUSIONS: T-TAS may be a useful tool for monitoring thrombogenicity and antithrombotic therapy in Fontan patients.

Persistent Patent Vertical Vein After Repair of Total Anomalous Pulmonary Venous Connection (TAPVR): A Rare Cause of Hypoxemia Post-Fontan Procedure.

Vertical vein (VV) ligation during total anomalous pulmonary venous return (TAPVR) repair is controversial. While some surgeons prefer ligation of the VV to prevent adverse sequelae of shunting across it and to promote flow through the newly created anastomosis, others leave it to serve as a "pop off valve" to the left heart structures, which are believed to be hypoplastic and noncompliant, presumably contributing to a more favorable post-operative outcome. We report two patients post-Fontan procedure, who underwent cardiac catheterization to explore the etiology of hypoxia and were found to have a persistent VV responsible for right to left shunting. Both patients underwent closure of the VV with improvement in the cyanosis and clinical course. These cases provide evidence supporting surgical ligation of the VV at the time of TAPVR repair, especially in patients with single ventricle.

20 years of experience with the Fontan procedure: characteristics and clinical outcomes of children in a tertiary referral hospital.

INTRODUCTION: Without participating in a contractile chamber, the Fontan procedure seeks to create a separation of oxygenated and deoxygenated blood in patients with univentricular heart, reducing the risks of long-term hypoxemia and improving their survival. This study describes the clinical outcomes of children undergoing the Fontan procedure between 2000 and 2020 in a tertiary referral hospital care centre in southwestern Colombia. MATERIALS AND METHODS: A retrospective observational descriptive study. The 81 patients who underwent the Fontan procedure were included. Categorical variables were presented with percentages and continuous variables with measures of central tendency according to the distribution of the data evaluated through the Shapiro-Wilk test. Sociodemographic, clinical, surgical variables, complications, and mortality were described. RESULTS: Between 2000 and 2020, 81 patients underwent the Fontan procedure: 43 (53.1%) males and a median age of 5.3 years (interquartile range 4.3-6.6). The most common diagnosis was tricuspid atresia (49.4%). The median mean pulmonary arterial pressure was 12 mmHg (interquartile range 10-15), the Nakata index 272 mm2/m2 (interquartile range 204-327), and the McGoon index (interquartile range 1.86-2.3). Seventy-two (88.9%) patients underwent extracardiac Fontan and 44 (54.3%) patients underwent fenestration. The median hospitalisation days were 19 days. The main complication was coagulopathy (19.8%), mortality in the first month between 2000 and 2010 was 8.6%, and after 2010 was 1.2%. CONCLUSION: The Fontan procedure is a palliative surgery for children with complex heart disease. According to anatomical and physiological variables, the proper choice of patients determines the short- and long-term results.

Cardiac MRI for Fontan candidates after intrapulmonary-artery septation.

Intrapulmonary-artery septoplasty may be effective for establishing two-lung Fontan circulation in patients with unilateral pulmonary circulation. However, evaluation of the function of each lung by conventional modalities can be challenging in these patients due to differing sources of blood flow to the left and right lungs following intrapulmonary-artery septation. Herein, we report a case in which two-lung Fontan circulation was successfully achieved after using cardiac MRI along with conventional modalities to evaluate pulmonary circulation.

Retrograde cerebral perfusion for intracardiac air embolism in Fontan procedure.

We report the case of a 5-year-old boy who suffered from an intracardiac air influx with suspected cerebral air embolism during the Fontan procedure. We immediately transformed the cardiopulmonary bypass circuit to perform a retrograde cerebral perfusion, which resulted in successful neuroprotection. He was extubated in the operating room without any neurological defects.

Fontan Hepatopathy-Managing Unknowns.

BACKGROUND AND AIMS: How to best monitor Fontan-associated liver disease (FALD) remains unclear. We describe results from a prospective liver care pathway in adults (n=84) with a Fontan circulation. METHODS: Routine assessment of the liver, by acoustic radiation force frequency and ultrasound was undertaken. Results, including liver biochemistry, systemic ventricular function (echocardiography), functional class, medication use and clinical endpoints (varices, hepatocellular carcinoma, heart transplantation and death) were collated. RESULTS: Most individuals returned a cirrhotic range acoustic radiation force impulse imaging (ARFI) result. ARFI values were greater in the proportion of individuals with hepatic nodularity (p=0.024). Univariate analysis demonstrated moderate correlation with platelet number (Spearmans rho= -0.376, p=0.049). Patients with clinical endpoints had lower platelets (p=0.012) but only a trend to hepatic nodularity (p=0.057). Clinical endpoints were more common in those with ventricular dysfunction (p=0.011). Multivariate analysis revealed that age at Fontan and being on angiotensin converting enzyme inhibitors (ACEI) predicted ARFI score (ß=0.06 [95% CI 0.01-0.09], p=0.007 and ß=0.53 [95% CI 0.17-0.89], p=0.005, respectively). However, these associations were not significant once adjusted for Fontan type, age at ARFI, systemic ventricle morphology, ventricle function, or Model for End-stage Liver Disease (MELD-XI) excluding international normalised ratio (INR) (p>0.05 for all). CONCLUSIONS: Ideal FALD monitoring remains unclear. ARFI has utility as a binary non-invasive indicator of cirrhosis, highlighting individuals who may need more frequent ongoing monitoring for hepatocellular carcinoma. However, no definite advantage to serial ARFI, once cirrhotic range ARFI results are present, has been identified.

New intra-conduit thrombus detected using transesophageal echocardiography immediately after weaning from cardiopulmonary bypass during the Fontan procedure: a case report.

This study reports a case wherein a new thrombus was detected by transesophageal echocardiography in the conduit during extracardiac conduit Fontan procedure. Immediately after weaning from the cardiopulmonary bypass and administration of protamine, a thrombus was noted in the conduit by transesophageal echocardiography. Since the patient was hemodynamically stable, anticoagulation therapy was initiated after admission to the intensive care unit. One week post-surgery, imaging results showed residual thrombus, but the patient was safely discharged. Even during Fontan procedure, careful observation with transesophageal echocardiography is important because of the possibility of thrombus formation in the conduit.

[Fontan-associated liver disease current status and transplantation consideration].

Fontan-associated liver disease (FALD) is one of the main complications after the Fontan procedure, manifesting mostly as liver fibrosis and even cirrhosis, with a high incidence rate and a lack of typical clinical symptoms that seriously affect patient prognosis. The specific cause is unknown, although it is considered to be associated with long-term elevated central venous pressure, impaired hepatic artery blood flow, and other relevant factors. The absence of association between laboratory tests, imaging data, and the severity of liver fibrosis makes clinical diagnosis and monitoring difficult. A liver biopsy is the gold standard for diagnosing and staging liver fibrosis. The most important risk factor for FALD is time following the Fontan procedure; therefore, it is recommended to do a liver biopsy 10 years after the Fontan procedure and to be cautious for the presence of hepatocellular carcinoma. Combined heart-liver transplantation is a recommended choice with favorable outcomes for patients with Fontan circulatory failure and severe hepatic fibrosis.

Neurocognitive Dysfunction and Smaller Brain Volumes in Adolescents and Adults With a Fontan Circulation.

BACKGROUND: Neurocognitive outcomes beyond childhood in people with a Fontan circulation are not well defined. This study aimed to investigate neurocognitive functioning in adolescents and adults with a Fontan circulation and associations with structural brain injury, brain volumetry, and postnatal clinical factors. METHODS: In a binational study, participants with a Fontan circulation without a preexisting major neurological disability were prospectively recruited from the Australia and New Zealand Fontan Registry. Neurocognitive function was assessed by using Cogstate software in 107 participants with a Fontan circulation and compared with control groups with transposition of the great arteries (n=50) and a normal circulation (n=41). Brain MRI with volumetric analysis was performed in the participants with a Fontan circulation and compared with healthy control data from the ABIDE I and II (Autism Brain Imaging Data Exchange) and PING (Pediatric Imaging, Neurocognition, and Genetics) data repositories. Clinical data were retrospectively collected. RESULTS: Of the participants with a Fontan circulation who had a neurocognitive assessment, 55% were male and the mean age was 22.6 years (SD 7.8). Participants with a Fontan circulation performed worse in several areas of neurocognitive function compared with those with transposition of the great arteries and healthy controls (P<0.05). Clinical factors associated with worse neurocognitive outcomes included more inpatient days during childhood, younger age at Fontan surgery, and longer time since Fontan procedure (P<0.05). Adults with a Fontan circulation had more marked neurocognitive dysfunction than adolescents with a Fontan circulation in 2 domains (psychomotor function, P=0.01 and working memory, P=0.02). Structural brain injury was present in the entire Fontan cohort; the presence of white matter injury was associated with worse paired associate learning (P<0.001), but neither the presence nor severity of infarct, subcortical gray matter injury, and microhemorrhage was associated with neurocognitive outcomes. Compared with healthy controls, people with a Fontan circulation had smaller global brain volumes (P<0.001 in all regions) and smaller regional brain volumes in most cerebral cortical regions (P<0.05). Smaller global brain volumes were associated with worse neurocognitive functioning in several domains (P<0.05). A significant positive association was also identified between global brain volumes and resting oxygen saturations (P≤0.04). CONCLUSIONS: Neurocognitive impairment is common in adolescents and adults with a Fontan circulation and is associated with smaller gray and white matter brain volume. Understanding modifiable factors that contribute to brain injury to optimize neurocognitive function is paramount.

Repeat radiofrequency catheter ablation of atrial tachycardias in patients with congenital heart disease.

INTRODUCTION: Atrial tachycardias (AT) in patients with congenital heart disease (CHD) are significantly contributing to morbidity and mortality. Aim of this study was to evaluate the long-term course of CHD patients requiring repeat ablation procedures (RAP) of AT. PATIENTS AND METHODS: All 144 patients with CHD who had undergone ablation of AT at our center between January 2003 and October 2018 were enrolled. Patients were classified according to the complexity of CHD: complex CHD (cCHD), moderate CHD (mCHD), and simple CHD (sCHD). RESULTS: A total of 101 RAP were performed in 64 patients. One RAP was performed in n = 40, two in n = 13, three in n = 10, and five in n = 1. Acute success rate was 82% (83/101) and was not associated with the complexity of CHD (p = 1.0). Number of procedures was lower in patients with sCHD than in patients with mCHD and cCHD (sCHD 1.3 ± 0.6, mCHD 1.8 ± 1.0, and cCHD 1.8 ± 1.1, p = .04). RAP were most frequent in patients after Fontan palliation or Atrial switch procedure (2.0 ± 1.1 [n = 41] vs. 1.6 ± 0.9 all others, p = .016) and in patients with multiple unstable AT's (2.5 ± 1.1 [n = 11] vs. 1.7 ± 1.0, p = .008). Major complications occurred in 4/101 procedures. Complete follow-up was available in 125 patients. Since last RAP 73% of the patients were in sinus/atrial rhythm and 34/125 patients (27%) with AT recurrence did not require re-ablation with mean follow-up of 52 ± 40 months. CONCLUSIONS: Recurrences after ablation of AT in CHD patients were frequent. After RAP promising long-term results could be achieved. Data encourage repetitive ablation procedures in this patient population.

Prediction of fluid responsiveness following liver compression in pediatric patients with single ventricle physiology.

INTRODUCTION: The role of liver compression in predicting fluid responsiveness in children with a single ventricle has never been evaluated. The purpose of this study was to assess whether blood pressure changes during liver compression predict fluid responsiveness in children with single ventricle physiology. METHODS: This prospective, interventional study included children aged 3 months to 5 years who underwent surgery for bidirectional cavopulmonary shunt or extracardiac Fontan operation. Before fluid loading, the right upper abdomen was compressed at 30 mmHg for 10 s, and changes in the blood pressure waves were recorded before administering 10 ml kg-1 of crystalloid solution. Systolic arterial pressure, diastolic arterial pressure, central venous pressure, pleth variability index, respiratory variation in aortic blood flow peak velocity, and stroke volume were measured before and after fluid loading. A volume responder was defined as a patient with >15% increase in stroke volume index. RESULTS: Thirty patients underwent bidirectional cavopulmonary shunt (15 responders and 15 non-responders), and 32 underwent Fontan surgery (17 responders and 15 non-responders). In children with bidirectional cavopulmonary shunt, Δsystolic arterial pressure > 8 mmHg (sensitivity 76.9% and specificity 93.3%), Δdiastolic arterial pressure > 7 mmHg (sensitivity 69.2% and specificity 93.3%), and Δmean arterial pressure > 7 mmHg (sensitivity 69.2% and specificity 100%) during liver compression predicted fluid responsiveness. The areas under the receiver operating characteristic curves of Δsystolic arterial pressure, Δdiastolic arterial pressure, and Δmean arterial pressure were 0.928, 0.859, and 0.874 (all p < .001). In children who underwent Fontan surgery, only Δsystolic arterial pressure > 16 mmHg was predictive of fluid responsiveness (sensitivity of 41.2% and specificity of 100%), with the areas under the receiver operating characteristic curves curve of 0.786 (p < .001). Pleth variability index and respiratory variation in aortic blood flow peak velocity had no predictive value for fluid responsiveness after both types of surgeries. DISCUSSION: In BCPS patients, liver compression increases the inferior vena cava flow which directly leads to an increase in preload. On the other hand, blood flow from the liver drains directly into the pulmonary arteries in Fontan circulation. Because of this characteristics for preload determination, the clinical application of liver compression to monitor hemodynamic changes might be more useful in patients with bidirectional cavopulmonary shunt than those with Fontan circulation. CONCLUSION: Increase in blood pressure induced by liver compression is predictive of fluid responsiveness in children with single ventricle physiology.