Comparative outcomes of cardioplegic arrest versus beating heart in pediatric undergoing extracardiac total cavopulmonary connection.

BACKGROUND: Total cavopulmonary connection (TCPC) is a definitive palliative procedure for functionally univentricular congenital heart disease. The study aims to compare the impact of on-pump cardioplegic arrest and on-pump beating heart cardiopulmonary bypass (CPB) on the prognosis of pediatric patients undergoing extracardiac TCPC. METHODS: The medical data of patients (< 18 years) who underwent extracardiac TCPC with CPB between January 2008 and December 2020 in the cardiac surgery center were retrospectively analyzed. Depending on CPB strategies, the patients were assigned to the beating-heart (BH) and cardioplegic arrest (CA) groups. Data including baseline characteristics, intra/postoperative variables, and clinical outcomes were collected for analysis with 1:1 propensity score matching and multivariable stepwise logistic regressions. RESULTS: Fifty-seven matched patient pairs were obtained. No significant difference existed between the two groups in the in-hospital mortality (3.5% vs. 1.8%, P = 1) and one-year survival rate (100% vs. 96.4%, P = 0.484). The BH group had significantly less intraoperative platelet transfusion (10 mL vs. 150 mL, P = 0.019) and blood loss (100 mL vs. 150 mL, P = 0.033) than the CA group. The CA group had significantly higher vasoactive-inotropic scores (P < 0.05) and longer postoperative ICU stays (2.0 d vs. 3.7 d, P = 0.017). No significant difference existed between the two groups in the incidence of postoperative adverse events. CONCLUSION: Although both CPB strategies are safe and feasible for extracardiac TCPC, the BH technique would cause less intraoperative platelet transfusion and blood loss, and achieve faster early-term postoperative recovery.

Incidence, pathophysiology, and treatment of failing Fontan after the total cavopulmonary connection.

BACKGROUND: Failing Fontan poses a significant clinical challenge. This study aims to improve patients' outcomes by comprehensively understanding the incidence, pathophysiology, risk factors, and treatment of failing Fontan after total cavopulmonary connection. METHODS: We performed a retrospective analysis of patients who underwent total cavopulmonary connection at the German Heart Center Munich between 1994 and 2022. The onset of failing Fontan was defined as: protein-losing enteropathy, plastic bronchitis, NYHA class IV, NYHA class III for > one year, unscheduled hospital admissions for heart failure symptoms, and evaluation for heart transplantation. RESULTS: Among 634 patients, 76 patients presented with failing Fontan, and the incidence was 1.48 per 100 patient-years. Manifestations included protein-losing enteropathy (n = 34), hospital readmission (n = 28), NYHA III (n = 18), plastic bronchitis (n = 16), evaluation for heart transplantation (n = 14), and NYHA IV (n = 4). Risk factors for the onset of failing Fontan were dominant right ventricle (p = 0.010) and higher pulmonary artery pressure before total cavopulmonary connection (p = 0.004). A total of 72 interventions were performed in 59 patients, including balloon dilatation/stent implantation in the total cavopulmonary connection pathway (n = 49) and embolization of collaterals (n = 24). Heart transplantation was performed in four patients. The survival after the onset of Fontan failure was 77% at 10 years. Patients with failing Fontan revealed significantly higher zlog-NT-proBNP levels after onset compared to those without (p = 0.021). CONCLUSIONS: The incidence of Fontan failure was 1.5 per 100 patient years. Dominant right ventricle and higher pulmonary artery pressure before total cavopulmonary connection were significant risks for the onset of failing Fontan. Zlog-NT-proBNP is only a late marker of Fontan failure.

Outcomes after bidirectional cavopulmonary shunt with antegrade pulmonary blood flow in high-risk patients.

OBJECTIVE: We have left antegrade pulmonary blood flow (APBF) at bidirectional cavopulmonary shunt (BCPS) only for high-risk patients. This study evaluates the indication and the outcomes of patients with APBF, compared to those without APBF. METHODS: Patients with APBF after BCPS were identified among patients who underwent BCPS between 1997 and 2022. Outcomes of patients with and without APBF after BCPS were compared. RESULTS: APBF was open in 38 (8.2%) of 461 patients. Median age (7.7 versus 6.3 months, p = 0.55) and weight (5.6 versus 6.1 kg, p = 0.75) at BCPS were similar in both groups. The most frequent indication for APBF was high pulmonary artery pressure (PAP) in 14 patients, followed by hypoxaemia in 10, and hypoplastic left pulmonary artery in 8. The source of APBF was the pulmonary trunk in 10 patients and the aortopulmonary shunt in 28. Median hospital stay after BCPS was longer (22 versus 14 days, p = 0.018) and hospital mortality was higher (10.5 versus 2.1%, p = 0.003) in patients with APBF compared to those without APBF. However, 448 hospital survivors showed similar survival after discharge following BCPS (p = 0.224). Survival after total cavopulmonary connection (TCPC) was similar between the groups (p = 0.753), although patients with APBF were older at TCPC compared to those without (3.9 versus 2.2 years, p = 0.010). CONCLUSION: APBF was left in 8% following BCPS in high-risk patients, mainly due to preoperative high PAP. Hospital survivors after BCPS demonstrated comparable survival in patients with and without APBF. Adding APBF at BCPS might be a useful option for high-risk patients.

Validating the Concept of Mechanical Circulatory Support with a Rotary Blood Pump in the Inferior Vena Cava in an Ovine Fontan Model.

Right-sided mechanical support of the Fontan circulation by existing devices has been compounded by the cross-sectional design of vena cava anastomosis to both pulmonary arteries. Our purpose was to investigate whether increasing inferior vena cava (IVC) flow with a rotary blood pump in the IVC only in an ovine animal model of Fontan would lead to acceptable superior vena cava (SVC) pressure. To achieve this, a Fontan circulation was established in four female sheep by anastomosing the SVC to the main pulmonary artery (MPA) and by interposing a Dacron graft between the IVC and the MPA. A rotary blood pump was then introduced in the graft, and the effect of incremental flows was observed at increasing flow regimen. Additionally, to stimulate increased pulmonary resistance, the experience was repeated in each animal with the placement of a restrictive band on the MPA distally to the SVC and Dacron graft anastomosis. Circulatory support of IVC flow alone increased the systemic cardiac output significantly, both with and without banding, indicating the feasibility of mechanical support of the Fontan circulation by increasing the flow only in the inferior vena cava. The increase in SVC pressure remained within acceptable limits, indicating the potential effectiveness of this mode of support. The findings suggest that increasing the flow only in the inferior vena cava is a feasible method for mechanical support of the Fontan circulation, potentially leading to an increase in cardiac output with acceptable increases in superior vena cava pressure.

Impact of veno-venous collaterals on outcome after the total cavopulmonary connection.

OBJECTIVE: To evaluate the prevalence of veno-venous collaterals (VVCs) after total cavopulmonary connection (TCPC) and analyze their impact on outcomes. METHODS: Patients undergoing TCPC between 1994 and 2022 were evaluated. VVCs were identified using angiograms of cardiac catheterizations and their impact on outcomes was analyzed. RESULTS: A total of 635 patients were included. Median age at TCPC was 2.3 (interquartile ranges (IQR): 1.8-3.3) years. The most frequent diagnosis was hypoplastic left heart syndrome in 173 (27.2%) patients. Prior bidirectional cavopulmonary shunt was performed in 586 (92.3%) patients at a median age of 5.3 (3.6-9.9) months. VVCs were found in 94 (14.8%) patients at a median of 2.8 (0.1-11.8) years postoperatively. The prevalence of VVCs was similar between the dominant right and left ventricle (14.7 vs. 14.9%, p = 0.967). Mean pulmonary artery pressure (16.2 vs. 16.0 mmHg, p = 0.902), left atrial pressure (5.5 vs. 5.7 mmHg, p = 0.480), transpulmonary gradient (4.0 vs. 3.8 mmHg, p = 0.554) and oxygen saturation (81.4 vs. 82.6%, p = 0.103) before TCPC were similar between patients with and without VVCs. The development of VVCs did not affect survival after TCPC (p = 0.161). Nevertheless, VVCs were a risk for the development of plastic bronchitis (PB, p < 0.001). Interventional closure of VVCs was performed in 60 (9.4%) patients at a median of 8.9 (0.6-15.1) years after TCPC, and improvement of oxygen saturation was observed in 66% of the patients. CONCLUSIONS: The prevalence of VVCs after TCPC was 15%. VVCs had no impact on survival following TCPC but were associated with a high prevalence of PB.

Cardiovascular Imaging-Derived Skeletal Muscle Mass Correlates With Fitness and Survival in Patients With Univentricular Circulation.

Aims This study aims to retrospectively quantify skeletal muscle mass from cardiovascular imaging studies in total cavopulmonary connection (TCPC) patients and to correlate calculated muscle mass with clinical outcomes. Materials and methods Ninety-one TCPC patients at a mean age of 24.0 ±5.5 years (37 women; 40.7%) who underwent chest computed tomography (CT) or cardiac magnetic resonance imaging (MRI) as part of their follow-up were identified in a single-center database. The cross-sectional skeletal muscle index (SMI) at the Th4 and Th12 levels was calculated from CT images, and the dorsal skeletal muscle area (SMA) at the Th12 level was measured from an MRI. Results Calculated SMI at Th12 level was 38.0 (34.5; 42.0) cm2.m-2 or 89.6 (81.9; 101.6) % of predicted values. The median follow-up from CT was 5.9 (3.1; 8.5) years, and the composite endpoint (death N=5, heart transplant N=6) was reached in a total of 11 (26.8%) patients. Patients with SMI (Th12) less than 90% of predicted values had a hazard ratio of 5.8 (95% CI: 1.2; 28.3) (p=0.03) for endpoint achievement. In the MRI group, dorsal SMA at the Th12 level was 27.6 ±5.1 cm2 in men and 20.0 ±5.8 cm2 in women. Correlations were found between SMA/kg and peak oxygen uptake (VO2 peak) (r=0.48, p=0.0005) and fat-free mass (r=0.63, p<0.0001), respectively. Conclusions A low SMI at the Th12 level was associated with a higher risk of death or cardiac transplantation. Evaluation of skeletal muscle mass using cardiovascular imaging methods allows rapid identification of individuals at risk of sarcopenia.

Relationship of Aortopulmonary Collaterals and Pulmonary Artery Development During Staged Single Ventricle Reconstruction.

To evaluate the relationship of aortopulmonary collaterals and the development of central pulmonary arteries during staged palliation. A total of 287 patients, who underwent staged palliation with bidirectional cavopulmonary shunt and total cavopulmonary connection between 2008 and 2019, had available angiography. Pulmonary artery index was calculated using pulmonary angiography as described by Nakata and colleagues. Aortopulmonary collaterals were observed in 47 (16%) patients at stage II palliation, in 131 (46%) at total cavopulmonary connection, and afterwards in 49 (7%). The interventional closure of aortopulmonary collaterals was performed before stage II in 12 (4%) patients, before Fontan completion in 38 (13%), and afterwards in 39 (14%). Presence of aortopulmonary collaterals before stage II was not associated with the pulmonary artery index (129 vs. 150 mm2/m2, p = 0.176) at stage II. In contrast, aortopulmonary collaterals before the Fontan completion were associated with lower pulmonary artery index (154 vs. 172 mm2/m2, p = 0.005), and right pulmonary artery index (99 vs. 106 mm2/m2, p = 0.006). Patients who underwent interventional closure of aortopulmonary collaterals before total cavopulmonary connection had lower pulmonary artery index (141 vs. 169 mm2/m2, p < 0.001), lower right pulmonary artery index (93 vs. 106 mm2/m2, p = 0.007), and left pulmonary artery index (54 vs. 60 mm2/m2, p = 0.013) at Fontan completion. The presence of aortopulmonary collaterals did not influence pulmonary artery size by the time of stage II. However, presence of aortopulmonary collaterals was associated with under-developed pulmonary arteries at Fontan completion, especially in patients who needed interventional closure of aortopulmonary collaterals.

The effect of the conduit size on middle-term outcomes in patients with extracardiac total cavopulmonary connection.

OBJECTIVES: The 18- and 16-mm conduits in extracardiac total cavopulmonary connection (eTCPC) were reported to be optimal based on energy loss and flow stagnation at the relatively early phase. However, because the artificial conduit lacks growth potential, we have recently encountered some cases in which the conduit needs to be changed several years after eTCPC. These cases prompted us to reconsider the surgical strategy for eTCPC. METHODS: We reviewed our 20-year single-centre experience with eTCPC patients (n = 256) to compare the 18-mm conduit (n = 195) and 16-mm conduit (n = 61) in terms of mortality and morbidity. RESULTS: The 16-mm conduit was used significantly more frequently in patients whose main chamber was right ventricle (P < 0.001). There was also a significant difference in preoperative inferior vena cava pressure (P = 0.008). There was a significant difference in the actuarial rate of freedom from late-occurring complications, including mortality, between the 2 groups (P = 0.003). There was a significant difference in the actuarial rate of reoperation-free survival (P = 0.042); however, there was no significant difference in resurgical intervention for the conduit (P = 0.333). In multivariate analysis, preoperative inferior vena cava pressure was an independent predictor for late-occurring complications (hazard ratio 1.19; P = 0.026). Conduit size (18 or 16 mm) itself was not an independent predictive factor for late-occurring complications (P = 0.690). CONCLUSIONS: The mid-term clinical outcomes in patients who underwent eTCPC were excellent with low mortality. Preoperative inferior vena cava pressure was the only predictive risk factor for postoperative morbidity, and the 16 mm conduit was not predictive thereof.

"Quality of life" analysis in the long-term follow-up after "Fontan" palliation for CHDs-a single-centre experience.

BACKGROUND: Complex CHDs are life threatening, and surgical treatment is needed for survival. Fontan palliation led to a significant increase in survival rates during the last decades. Consequently, quality of life became more essential. While a reduced quality of life compared to healthy children has been reported, detailed knowledge about individual quality of life and particular areas is lacking. Furthermore, the effect of different risk factors on quality of life is only rarely evaluated. METHOD AND RESULTS: Database of the department for pediatric cardiology, Heart Center Leipzig, was screened for children after total cavopulmonary connection palliation. n = 39 patients were included in the study, the outcome after total cavopulmonary connection was analysed in detail and quality of life data were collected and analysed using the standardised questionnaire "Pediatric quality of life inventory", version 4.0. We compared the total health score of our patients to the mean score of healthy children in the literature. The mean follow-up time was 6.4 ± 3.2 years, the overall survival was 100% after maximal follow-up time of 11.1 years. We could not find any age or gender dependence, nor an influence of age at total cavopulmonary connection on the later quality of life. Yet, patients with three-staged surgery exhibited a worse quality of life than patients with two-staged palliation. Late complications might influence quality of life, but patient number is too small, to find universal results. CONCLUSION: The total cavopulmonary connection palliation affects physical and psychological quality of life as well as cardiac health independently from age and gender. More patients and longer observation should be examined to confirm the results.

Impact of early postoperative haemodynamic and laboratory parameters on outcome after the Fontan procedure.

OBJECTIVE: To identify early postoperative haemodynamic and laboratory parameters predicting outcomes following total cavopulmonary connection. METHODS: Patients who underwent total cavopulmonary connection between 2012 and 2021 were evaluated. Serial values of mean pulmonary artery pressure, mean arterial pressure, peripheral oxygen saturation, and lactate levels were collected. The influence of these variables on morbidities was analyzed. Cut-off values were calculated using the receiver operating characteristic analysis. RESULTS: A total of 249 patients were included. All patients had previous bidirectional cavopulmonary shunt. Median age and weight at total cavopulmonary connection were 2.2 (1.8-2.7) years and 11.7 (10.7-13.4) kg, respectively. All patients were extubated in the ICU at a median of 3 (2-5) hours after ICU admission. Postoperative pulmonary artery pressure, around 12 hours after extubation, was significantly associated with chest tube drainage (p = 0.048), chylothorax (p = 0.021), ascites (p = 0.016), and adverse events (p = 0.028). Receiver operating characteristic analysis revealed a cut-off value of 13-15 mmHg for chest tube drainage and chylothorax and 17 mmHg for ascites and adverse events. Mean arterial pressure 1 hour after extubation was associated with prolonged chest tube drainage (p = 0.015) and adverse events (p = 0.008). Peripheral oxygen saturation 6 hours after extubation (p = 0.003) was associated with chest tube duration and peripheral oxygen saturation 1 hour after extubation (p < 0.001) was associated with ascites. Lactate levels on 2nd postoperative day (p = 0.022) were associated with ascites and lactate levels on 1st postoperative day (p = 0.009) were associated with adverse events. CONCLUSIONS: Higher pulmonary artery pressure, lower mean arterial pressure, lower peripheral oxygen saturation, and higher lactate in early postoperative period, around 12 hours after extubation, predicted in-hospital and post-discharge adverse events following total cavopulmonary connection.

Tachyarrhythmia after the total cavopulmonary connection: incidence, prognosis, and risk factors.

OBJECTIVE: The purpose of this study is to evaluate the incidence and outcomes regarding tachyarrhythmia in patients after total cavopulmonary connection. METHODS: A retrospective analysis of 620 patients who underwent total cavopulmonary connection between 1994 and 2021 at our institution was performed. Incidence of tachyarrhythmia was depicted, and results after onset of tachyarrhythmia were evaluated. Factors associated with the onset of tachyarrhythmia were identified. RESULTS: A total of 52 (8%) patients presented with tachyarrhythmia that required medical therapy. Onset during hospital stay was observed in 27 patients, and onset after hospital discharge was observed in 32 patients. Freedom from late tachyarrhythmia following total cavopulmonary connection at 5, 10, and 15 years was 97, 95, and 91%, respectively. The most prevalent late tachyarrhythmia was atrial flutter (50%), followed by supraventricular tachycardia (25%) and ventricular tachycardia (25%). Direct current cardioversion was required in 12 patients, and 7 patients underwent electrophysiological study. Freedom from Fontan circulatory failure after onset of tachyarrhythmia at 10 and 15 years was 78% and 49%, respectively. Freedom from occurrence of decreased ventricular systolic function after the onset of tachyarrhythmia at 5 years was 85%. Independent factors associated with late tachyarrhythmia were dominant right ventricle (hazard ratio, 2.52, p = 0.02) and weight at total cavopulmonary connection (hazard ratio, 1.03 per kilogram; p = 0.04). Type of total cavopulmonary connection at total cavopulmonary connection was not identified as risk. CONCLUSIONS: In our large cohort of 620 patients following total cavopulmonary connection, the incidence of late tachyarrhythmia was low. Patients with dominant right ventricle and late total cavopulmonary connection were at increased risk for late tachyarrhythmia following total cavopulmonary connection.

Brady-arrhythmias requiring permanent pacemaker implantation during and after staged Fontan palliation.

BACKGROUND: Brady-arrhythmia requiring pacemaker implantation remains one of the Fontan-specific complications before and after total cavopulmonary connection. METHODS: A retrospective analysis of 620 patients who underwent total cavopulmonary connection between 1994 and 2021 was performed to evaluate the incidence of brady-arrhythmia and the outcomes after pacemaker implantation. Factors associated with the onset of brady-arrhythmia were identified. RESULTS: A total of 52 patients presented with brady-arrhythmia and required pacemaker implantation. Diagnosis included 16 sinus node dysfunctions, 29 atrioventricular blocks, and 7 junctional escape rhythms. Pacemaker implantation was performed before total cavopulmonary connection (n = 16), concomitant with total cavopulmonary connection (n = 8), or after total cavopulmonary connection (n = 28, median 1.8 years post-operatively). Freedom from pacemaker implantation following total cavopulmonary connection at 10 years was 92%. Twelve patients needed revision of electrodes due to lead dysfunction (n = 9), infections (n = 2), or dislocation (n = 1). Lead energy thresholds were stable, and freedom from pacemaker lead revision at 10 years after total cavopulmonary connection was 78%. Congenitally corrected transposition of the great arteries (odds ratio: 6.6, confidence interval: 2.0-21.5, p = 0.002) was identified as a factor associated with pacemaker implantation before total cavopulmonary connection. Pacemaker rhythms for Fontan circulation were not a risk factor for survival (p = 0.226), protein-losing enteropathy/plastic bronchitis (p = 0.973), or thromboembolic complications (p = 0.424). CONCLUSIONS: In our cohort of patients following total cavopulmonary connection, freedom from pacemaker implantation at 10 years was 92% and stable atrial and ventricular lead energy thresholds were observed. Congenitally corrected transposition of the great arteries was at increased risk for pacemaker implantation before total cavopulmonary connection. Having a pacemaker in the Fontan circulation had no adverse effect on survival, protein-losing enteropathy/plastic bronchitis, or thromboembolic complications.

Impact of aortopulmonary collaterals on adverse events after total cavopulmonary connection.

OBJECTIVES: Effects of aortopulmonary collaterals (APCs) on outcomes after the total cavopulmonary connection (TCPC) are unclear. This study evaluated the incidence of APCs before and after TCPC and analysed the impacts of APCs on adverse outcomes. METHODS: A total of 585 patients, who underwent TCPC from 1994 to 2020 and whose preoperative angiographies were available, were included. Pre-TCPC angiograms in all patients were used for the detection of APCs, and post-TCPC angiograms were evaluated in selected patients. Late adverse events included late death, protein-losing enteropathy (PLE) and plastic bronchitis (PB). RESULTS: The median age at TCPC was 2.3 (1.8-3.4) years with a body weight of 12 (11-14) kg. APCs were found in 210 patients (36%) before TCPC and in 81 (14%) after TCPC. The closure of APCs was performed in 59 patients (10%) before TCPC, in 25 (4.2%) at TCPC and in 59 (10%) after TCPC. The occurrences of APCs before and after TCPC were not associated with short-term or mid-term mortality. The APCs before TCPC were associated with chylothorax (P = 0.025), prolonged chest tube duration (P = 0.021) and PB (P = 0.008). The APCs after TCPC were associated with PLE (P < 0.001) and PB (P < 0.001). With APCs following TCPC, freedom from PLE and PB was lower than without (P < 0.001, P < 0.001). CONCLUSIONS: APCs before TCPC were associated with chylothorax, prolonged chest tube duration and PB. APCs after TCPC were associated with both PLE and PB. The presence of APCs might affect the lymph drainage system and increase the incidence of chylothorax, PLE and PB.

Recanalized vein of marshall following bidirectional glenn surgery.

A 6-year-old boy with a case of double outlet right ventricle with large non-routable ventricle septal defect and severe pulmonary stenosis was deemed unsuitable for biventricular repair on a prior evaluation. Hence, a bidirectional Glenn (BDG) shunt was performed at 3 years of age following cardiac catheterization.

Acute ST-elevation myocardial infarction with Guillain-Barre syndrome in Fontan circulation.

Total cavopulmonary connection, commonly referred to as the Fontan procedure, is the established destination therapy for univentricular hearts. While the procedure permits a longer survival of these patients, this circulation involves several compromises from normal human circulation and poses several challenges with increasing age after surgery. We present an instance of acute ST-elevation myocardial infarction with Guillain-Barre syndrome in an adult after Fontan palliation and discuss the challenges in management.

Numerical simulation of the cavopulmonary connection flow with conduit stenoses of varying configurations.

The circulation in the total cavopulmonary connection (TCPC) is a low-energy system which operation and efficiency are subjected to multiple factors. Some retrospective studies report that the abnormal narrowing of vessels in the system, i.e. stenosis, is one of the most dangerous geometric factors which can result in heart failure. In the present study, the effect of varying extracardiac conduit (ECC) stenosis on the hemodynamics in a surrogate TCPC model is investigated using high-fidelity numerical simulations. The efficiency of the surrogate TCPC model was quantified according to the power loss, relative perfusion in lungs and the percentage of conduit surface area with abnormally low and high wall shear stress for venous flow. Additionally, the impact of respiration and asymmetry in the stenosis geometry to the system was examined. The results show that the flow in the TCPC model exhibits pronounced unsteadiness even under the steady initial boundary conditions, while the uneven pulmonary flow distribution and the presence of the ECC stenosis amplify the chaotic nature of the flow. Energy efficiency of the system is shown to strongly correlate with amount of vortical structures in the model and their range of scales. Finally, the study demonstrates that the presence of respiration in the model adds to perturbations in the flow which causes increase in the power loss. Results obtained in the study provide valuable insights on how the ECC stenosis effect the flow in the surrogate TCPC model under different flow conditions.

Protein-Losing Enteropathy and Plastic Bronchitis Following the Total Cavopulmonary Connections.

BACKGROUND: We aimed to evaluate incidence, outcomes, and predictors of protein-losing enteropathy (PLE) and plastic bronchitis (PB) in a cohort of total cavopulmonary connection (TCPC). METHODS: We included 620 consecutive patients undergoing TCPC between 1994 and 2021. Prevalence and predictors for onset of PLE/PB were evaluated. Death and heart transplantation after onset of PLE/PB were examined. RESULTS: A total of 41 patients presented with PLE/PB (31 with PLE, 15 with PB, and 5 developed both PLE and PB). Their median age at TCPC was 2.2 (interquartile ranges [IQRs], 1.7-3.7) years, and time period to onset for PLE was 2.6 (IQR: 1.0-6.6) years and for PB was 1.1 (IQR: 0.3-4.1) years after TCPC. Independent factors for developing PLE/PB were dominant right ventricle (RV, hazard ratio [HR], 2.243; 95% confidence interval [CI], 1.129-4.458, P = .021) and prolonged pleural effusion after TCPC (HR, 2.101; 95% CI, 1.090-4.049, P = .027). In PLE/PB population, freedom from death or transplantation after PLE/PB diagnosis at 5 and 10 years were 88.7% and 76.4%, respectively. Eleven surgical interventions were performed in 10 patients, comprising atrioventricular valve repairs (n = 4), Fontan pathway revisions (n = 2), pacemaker implantation (n = 2), secondary fenestration (n = 1), diaphragm plication (n = 1), and ventricular assist device implantation (n = 1). In nine patients, a recovery from PLE with the resolution of PLE symptoms and normal protein levels was achieved. Eight patients died and the remaining continued to have challenging protein loss. CONCLUSIONS: Protein-losing enteropathy and PB remain severe complications in the cohort of TCPC. Patients with dominant RV, and prolonged pleural effusions, were at risk for PLE/PB.

Virtual surgery to predict optimized conduit size for adult Fontan patients with 16-mm conduits.

OBJECTIVES: Recent evidence suggests that conduits implanted in Fontan patients at the age of 2-4 years become undersized for adulthood. The objective of this study is to use computational fluid dynamic models to evaluate the effect of virtual expansion of the Fontan conduit on haemodynamics and energetics of the total cavopulmonary connection (TCPC) under resting conditions and increased flow conditions. METHODS: Patient-specific, magnetic resonance imaging-based simulation models of the TCPC were performed during resting and increased flow conditions. The original 16-mm conduits were virtually enlarged to 3 new sizes. The proposed conduit sizes were defined based on magnetic resonance imaging-derived conduit flow in each patient. Flow efficiency was evaluated based on power loss, pressure drop and resistance and thrombosis risk was based on flow stagnation volume and relative residence time (RRT). RESULTS: Models of 5 adult patients with a 16-mm extracardiac Fontan connection were simulated and subsequently virtually expanded to 24-32 mm depending on patient-specific conduit flow. Virtual expansion led to a 40-65% decrease in pressure gradient across the TCPC depending on virtual conduit size. Despite improved energetics of the entire TCPC, the pulmonary arteries remained a significant contributor to energy loss (60-73% of total loss) even after virtual surgery. Flow stagnation volume inside the virtual conduit and surface area in case of elevated RRT (>20/Pa) increased after conduit enlargement but remained negligible (flow stagnation <2% of conduit volume in rest, <0.5% with exercise and elevated RRT <3% in rest, <1% with exercise). CONCLUSIONS: Virtual expansion of 16-mm conduits to 24-32 mm, depending on patient-specific conduit flow, in Fontan patients significantly improves TCPC efficiency while thrombosis risk presumably remains low.

Longitudinal analysis of systemic ventricular function and atrioventricular valve function after the Fontan procedure.

OBJECTIVES: This study aimed to determine the longitudinal change of systemic ventricular function and atrioventricular valve (AVV) regurgitation after total cavopulmonary connection (TCPC). METHODS: In 620 patients who underwent TCPC between 1994 and 2021, 4219 longitudinal echocardiographic examinations of systemic ventricular function and AVV regurgitation were evaluated retrospectively. RESULTS: The most frequent primary diagnosis was hypoplastic left heart syndrome in 172, followed by single ventricle in 131, tricuspid atresia in 95 and double inlet left ventricle (LV) in 91 patients. Dominant right ventricle (RV) was observed in 329 (53%) and dominant LV in 291 (47%). The median age at TCPC was 2.3 (1.8-3.4) years. Transplant-free survival at 5, 10 and 15 years after TCPC was 96.3%, 94.7% and 93.6%, respectively, in patients with dominant RV and 97.3%, 94.6% and 94.6%, respectively, in those with dominant LV (P = 0.987). Longitudinal analysis of systemic ventricular function was similar in both groups during the first 10 years postoperatively. Thereafter, systemic ventricular function worsened significantly in patients with dominant RV, compared with those with dominant LV (15 years: P = 0.007, 20 years: P = 0.03). AVV regurgitation was more frequent after TCPC in patients with dominant RV compared with those with dominant LV (P < 0.001 at 3 months, 3 years, 5 years, 10 years and 15 years, P = 0.023 at 20 years). There was a significant correlation between postoperative systemic ventricular dysfunction and AVV regurgitation (P < 0.001). CONCLUSIONS: There were no transplant-free survival difference and no difference in ventricular function between dominant RV and dominant LV for the first 10 years after TCPC. Thereafter, ventricular function in dominant RV was inferior to that in dominant LV. The degree of AVV regurgitation was significantly higher in dominant RV, compared with dominant LV, and it was positively associated with ventricular dysfunction, especially in dominant RV.

The impact of pulmonary artery size on midterm outcomes after nonfenestrated Fontan operation.

OBJECTIVE: We sought to identify the impact of pulmonary artery size on outcomes after nonfenestrated total cavopulmonary connection. In a subgroup of patients with right-sided bidirectional cavopulmonary shunt, the impact of each branch pulmonary artery size was individually determined. METHODS: The medical records of all patients who underwent nonfenestrated total cavopulmonary connection between 2009 and 2021 were reviewed. The pulmonary artery index was calculated using angiography before the operation. RESULTS: A total of 247 patients were included in this study. A right-sided bidirectional cavopulmonary shunt was performed in 217 patients (88%). Median pulmonary artery index was 162 (133-207) mm2/m2 before total cavopulmonary connection. Chylothorax occurred in 55 patients (22%). Pulmonary artery index was an independent factor for chylothorax (odds ratio, 0.98, 95% confidence interval, 0.97-0.99, P < .001) with a cutoff value of 170 mm2/m2. In a subgroup of patients with right-sided bidirectional cavopulmonary shunt, the left pulmonary artery index was identified as an independent risk factor for longer stay in the intensive care unit (coefficient B -0.02, 95% confidence interval, -0.04 to -0.002, P = .034) and for adverse events (hazard ratio, 0.98, 95% confidence interval, 0.96-0.99, P = .011) with a cutoff value of 56 mm2/m2. CONCLUSIONS: The pulmonary artery index is significantly associated with the occurrence of chylothorax after nonfenestrated total cavopulmonary connection with a cutoff value of 170 mm2/m2. In patients with right-sided bidirectional cavopulmonary shunt, left pulmonary artery index has a significant predictive value for longer stay in the intensive care unit and adverse events with a cutoff value of 56 mm2/m2.