When to intervene the pulmonary artery: Importance of anatomical assessment in the diagnosis of pulmonary artery coarctation.

OBJECTIVE: Pulmonary artery coarctation (PACoA) is a major problem that increases the frequency of intervention. However, there is little evidence regarding the prediction of PACoA development. METHODS: A retrospective chart review was performed on 42 patients who underwent modified Blalock-Taussig shunt and preoperative contrast-enhanced computed tomography. An uneven PA branching was defined as an abnormal ductus arteriosus connection to the left PA distal to the PA branching on contrast-enhanced computed tomography. RESULTS: Nineteen (45.2%) of 42 patients were diagnosed with PACoA. The median diameters of the ductus on the aorta and PA sides were 4.1 mm and 3.6 mm in the PACoA group and 3.6 mm and 2.9 mm in the non-PACoA group, respectively (P = .07 and .28, respectively). Tortuous ductus was recognized in 7 (36.8%) patients in the PACoA group and 14 (60.8%) patients in the non-PACoA group (P = .12). PACoA was associated with pulmonary atresia (16 patients [84.2%] in the PACoA group and 12 patients [52.1%] in the non-PACoA group) (P = .02). All 19 patients had uneven PA branching in the PACoA group, whereas 5 of 23 (21.7%) patients had uneven PA branching in the non-PACoA group (P < .001). CONCLUSIONS: Uneven PA branching rather than the ductus arteriosus size was strongly associated with PACoA development; therefore, morphologic assessment by contrast-enhanced computed tomography should be considered in patients with pulmonary atresia.

The Effect of Perioperative Fluid Management and Operative Modifications on Mortality and Morbidity in Patients Undergoing Pulmonary Endarterectomy.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension (CTEPH) is a severe disease treated with pulmonary endarterectomy. Our study aims to reveal the differences in liquid modalities and operation modifications, which can affect the patients' mortality and morbidity. METHODS: One hundred twenty-five patients who were diagnosed with CTEPH and underwent pulmonary thromboendarterectomy (PTE) at our center between February 2011 and September 2013 were included in this retrospective study with prospective observation. They were in New York Heart Association functional class II, III, or IV, and mean pulmonary artery pressure was > 40 mmHg. There were two groups, the crystalloid (Group 1) and colloid (Group 2) liquid groups, depending on the treatment fluids. P-value < 0.05 was considered statistically significant. RESULTS: Although the two different fluid types did not show a significant difference in mortality between groups, fluid balance sheets significantly affected the intragroup mortality rate. Negative fluid balance significantly decreased mortality in Group 1 (P<0.01). There was no difference in mortality in positive or negative fluid balance in Group 2 (P>0.05). Mean duration of stay in the intensive care unit (ICU) for Group 1 was 6.2 days and for Group 2 was 5.4 days (P>0.05). Readmission rate to the ICU for respiratory or non-respiratory reasons was 8.3% (n=4) in Group 1 and 11.7% (n=9) in Group 2 (P>0.05). CONCLUSION: Changes in fluid management have an etiological significance on possible complications in patient follow-up. We believe that as new approaches are reported, the number of comorbid events will decrease.

Hemodynamic Assessment of a Large Pulmonary Arteriovenous Malformation in a Neonate: Case Report and Review of Literature.

Herein we report the case of a neonate with a prenatally diagnosed large pulmonary arteriovenous malformation, managed with minimally invasive hemodynamic monitoring in our Neonatal Intensive Care Unit. The combination of Near-Infrared Spectroscopy and Pressure Recording Analytical Method could guide neonatal management of critical cases of vascular anomalies: immediate data are offered to clinicians, from which therapeutic decisions such as timing of surgical resection are made to achieve a positive outcome. We also systemically collected and summarized information on patients' characteristics of previous cases reported in literature to data, and we compared them to our case.

Proposition of quantitative parameters for pre- and early post-operative assessment in pulmonary thromboendarterectomy - An Indian prospective study.

INTRODUCTION: Chronic thromboembolic pulmonary hypertension results from the incomplete resolution of the vascular obstruction associated with pulmonary embolism. Symptoms are exertional dyspnoea and fatigue, and over a period of time, right ventricular dysfunction sets in. Pulmonary thromboendarterectomy is an effective surgical remedy for this condition. Our study is an initial post-operative experience of pulmonary thromboendarterectomy and we have also tried to formulate quantitative parameters for the prediction of the post-operative course in patients who are undergoing surgery. METHODS: Twenty patients with chronic thromboembolic pulmonary hypertension underwent pulmonary thromboendarterectomy between July 2017 and January 2020. Pre-operatively, each patient was subjected to the (i) 6-min walk test, (ii) pre-operative brain natriuretic peptide values and (iii) pulmonary artery systolic pressure. Following the surgery and subsequent discharge, the patients were followed up at intervals of 15 days, 1, 3, 6, 9 months and at 1 year. At one year post-operatively, the same three quantitative tests were performed on each subject. RESULTS: Post-operatively, the mean 6-min walk distance was 499.75 m as against 341.35 m pre-operatively (p < 0.0001). Mean brain natriuretic peptide was 8.69 pm/l as against 47.58 pm/l pre-operatively (p < 0.0001). Mean pulmonary artery systolic pressure was 22.25 as against 67.1 pre-operatively (p < 0.0001). CONCLUSION: 6-Min walk test, brain natriuretic peptide and pulmonary artery systolic pressure could be considered as useful predictors of the haemodynamic severity of disease and predict the post-operative outcome.

Serial right heart catheter assessment between balloon pulmonary angioplasty sessions identify procedural factors that influence response to treatment.

BACKGROUND: Balloon pulmonary angioplasty (BPA) is delivered as a series of treatments for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) however, there is little published data on the procedural determinants of outcome. METHODS: Pre- and post-BPA clinical and hemodynamic data, as well as serial hemodynamic and procedural data at each BPA session were evaluated to determine patient and procedure-related factors that influence hemodynamic response. RESULTS: Per procedure data from 210 procedures in 84 patients and per patient data from 182 procedures in 63 patients with completed treatment and 3-month follow-up were analyzed. A median of 3 (range 1-6) BPA procedures treating a median of 2 segments per procedure (range 1-3) were performed per patient with a median interval between procedures of 42 (range 5-491) days. Clinical outcome correlated with hemodynamic change (pulmonary vascular resistance [ΔPVR] vs Cambridge Pulmonary Hypertension Outcome Review [CAMPHOR] symptom score: p < 0.001, Pearson's r = 0.48, n = 49). Responders to BPA had more severe disease at baseline and 37.5 % of non-responders were post-PEA. There was a dose-response relationship between per procedure and total number of segments treated and hemodynamic improvement (ΔPVR: 1 segment: -0.9%, 2: -14.5%, 3 or more: -16.1%, p < 0.001). Treating totally occluded vessels had a greater hemodynamic effect (mean pulmonary artery pressure [ΔmPAP]: sessions with occlusion: -8.0%, without occlusion treated: -3.2%, p < 0.05) without an increased complication rate. CONCLUSIONS: The magnitude of clinical benefit is related to the hemodynamic effect of BPA which in turn is related to the number of segments treated and lesion severity. Patients who were post-PEA were less likely to respond to BPA.

Assessment of oxygenation after balloon pulmonary angioplasty for patients with inoperable chronic thromboembolic pulmonary hypertension.

BACKGROUND: The efficacy of balloon pulmonary angioplasty (BPA) in patients with inoperable chronic thromboembolic pulmonary hypertension would be promising. However, some patients showed residual dyspnea or symptoms, despite normalized hemodynamics. We aimed to clarify the clinical impact of oxygenation parameters on BPA outcome. METHOD: Ninety-nine consecutive patients who underwent BPA from September 2011 to December 2019 were enrolled. We evaluated hemodynamics with right heart catheterization, arterial blood gas examination, New York Heart Association functional class (NYHA-FC), respiratory function tests, nocturnal oximetry, and exercise capacity (6-min walk test and cardiopulmonary exercise testing) at baseline and after BPA. RESULT: Nearly normal hemodynamics was achieved after BPA (mean pulmonary artery pressure (PAP): 37.5 ± 10.0 to 20.6 ± 4.9 mmHg, p < 0.01). Oxygenation slightly improved (partial pressure of arterial oxygen; 61.5 ± 12.3 to 67.7 ± 12.7 mmHg, p < 0.01). Exertional desaturation remained unchanged (-8.1 ± 4.8 to -7.8 ± 5.1, p = 0.59), and this was associated with residual symptom (NYHA-FC ≥ 2) after BPA (OR 0.591, 95% CI 0.416-0.840, p = 0.003) in multivariate regression analyses. Lower vital capacity (r2 = 0.03, p = 0.01), higher mean PAP (r2 = 0.08, p = 0.02), and higher minute ventilation/carbon dioxide production (VE/VCO2) slope (r2 = 0.18, p < 0.01), the marker of ventilatory inefficiency, were correlated with exertional desaturation after BPA in multivariate linear analyses. CONCLUSION: Although hemodynamics nearly normalized, oxygenation did not. Moreover, exertional desaturation remained unchanged. This might cause residual symptom after BPA. Residual pulmonary hypertension suggesting incurable arteriopathy, and higher VE/VCO2 slope suggesting ventilation-perfusion mismatch might be related to exertional desaturation. Domiciliary oxygen therapy should be continued, if necessary.

On-Table Verification of Aortopulmonary Shunt Patency Through Ipsilateral Pulmonary Venous Blood Flow Assessment by Transesophageal Echocardiography.

Intraoperative transesophageal echocardiography is a well-established modality for the evaluation of the adequacy of the surgical repair of complex congenital heart lesions. This case report highlights the important role played by real-time transesophageal echocardiography during the evaluation of the patency of a left modified Blalock-Taussig shunt in a child with pulmonary atresia, nonconfluent pulmonary arteries, and borderline hemodynamic/ventilator parameters. Changes observed in the pulmonary venous blood flow pattern provided reassurance to the surgical team about the patency of the shunt and thereby avoided its reconstruction.

The impact of compliance on Stage 2 uni-ventricular heart circulation: An experimental assessment of the Bidirectional Glenn.

The Bidirectional Glenn (BDG) or cavopulmonary connection is typically undertaken to volume unload the single ventricle in an effort to preserve ventricular and atrioventricular valve function. The geometry of this surgical palliation has been shown to influence the fluid energy loss as well as the distribution of flow that enters through the superior vena cava. In-vitro and in-silico studies to date have been performed on rigid wall models, while this investigation looks at the impact of flexible thin walled models versus rigid walls. Rigid and compliant models of two patient-specific Glenn geometries were fabricated and tested under various flow conditions, within a biosimulator capable of replicating patient specific flow conditions. It was found that the compliant models exhibit greater levels of energy loss compared to the rigid models. Along with these findings greater levels of turbulence was found in both compliant models compared to their rigid counterparts under ultrasound examinations. This shows that vessel compliance has a significant impact on the hemodynamics within hypoplastic left heart syndrome.

CardioMEMSTM System in the Daily Management of Heart Failure: Review of Current Data and Technique of Implantation.

INTRODUCTION: Heart failure (HF) leads to significant morbidity and mortality and imposes a large economic burden. Although there have been several advances in HF monitoring and management, HF-rehospitalization remains a significant problem. Remote monitoring of HF to detect early signs of decompensation has emerged in past years as an option to prevent or reduce the incidence of HF rehospitalization. The CardioMEMSTM HF system is a wireless pulmonary artery (PA) pressure monitoring system that detects changes in PA pressure and transmits data to the healthcare provider. Since changes in PA pressure happen early in the course of HF decompensation, the CardioMEMSTM system allows the provider to institute timely intensification of HF therapies to alter the course. In trial and registry data, the use of the CardioMEMSTM HF system has been associated with reduction in HF hospitalization, improvement in quality of life, symptoms, and physical activity. AREAS COVERED: This review will focus on the available data supporting its utilization in patients with HF. EXPERT OPINION: CardioMEMSTM is relatively safe and cost-effective, reduces heart failure hospitalization rates, and fits into intermediate to high-value medical care.

Saline Contrast Transesophageal Echocardiography in Fontan Patients: Assessment of the Presence, Type, and Size of Right to Left Shunts.

Right to left (R-L) shunts resulting in cyanosis or systemic embolization occur after the Fontan procedure. The primary modality of diagnosing these is angiography. Successful delineation of these shunts in Fontan patients using selective saline contrast transesophageal echocardiography (SCTEE) may allow for reduced radiation and contrast exposure. We hypothesized that SCTEE could accurately determine the presence, type, and semiquantitative shunt size of R-L shunts in Fontan patients. SCTEE was performed in Fontan patients undergoing angiography for clinical indications. Injections were performed in six sites: mid-Fontan, right and left pulmonary arteries, superior and inferior vena cavae, and innominate vein. R-L shunt size was subjectively graded as 0 = absent, 1 = small, and 2 = medium or large based on echo contrast density in the left atrium. SCTEE was compared to angiography. 33 patients with Fontan were studied with median age 15 years, median weight 50.1 kg, and median O2 saturation of 90% in the R-L shunt group and 95% in the no R-L shunt group. R-L shunt types included intracardiac shunts (ICS), veno-venous collaterals (VVCs), arteriovenous malformations (AVMs), and their combinations. SCTEE versus angiography results were the same for the presence, type, and size of R-L shunts in 79% (26/33). SCTEE identified shunts in 88% (29/33). Angiography identified shunts in 85% (28/33). Neither method missed any medium or large R-L shunts. SCTEE and angiography had similar accuracy. SCTEE accurately detected the presence, type, and size of R-L shunts in most Fontan patients in this study. This can be used to guide targeted angiography, reducing radiation exposure and contrast load.

Assessment of the Reconstructed Pulmonary Circulation With Lung Perfusion Scintigraphy After Unifocalization and Repair of Tetralogy of Fallot With Major Aortopulmonary Collaterals.

BACKGROUND: Pulmonary vascular supply in tetralogy of Fallot (TOF) with major aortopulmonary collaterals (MAPCAs) is highly variable. Our approach to surgical management of this condition emphasizes early repair including unifocalization and reconstruction of the pulmonary circulation, incorporating all lung segments and addressing stenoses both proximal to and within the lung, in addition to ventricular septal defect closure. At our institution, we have over 15 years of experience using lung perfusion scintigraphy (LPS) to assess the distribution of pulmonary blood flow after complete unifocalization and repair. METHODS: We reviewed clinical and quantitative LPS data in 310 patients who underwent complete unifocalization and repair of TOF/MAPCAs from 2003 to 2018 at our institution. Postrepair relative lung perfusion distributions were determined from LPS initially obtained at our institution within 60 days after repair and thereafter. RESULTS: Total lung perfusion to the right and left lungs was 58.0% ± 14.2% and 42.0% ± 14.2%, respectively. Perfusion was balanced in 75% of patients and unbalanced in 25%, including 11% in whom it was extremely unbalanced. On multivariable analysis, older age at repair, surgery other than a single-stage complete unifocalization, and native anatomy consisting of unilateral pulmonary blood supply through a ductus arteriosus were associated with unbalanced perfusion. CONCLUSION: We present our experience using LPS as an outcome measure after surgical repair of TOF/MAPCAs. Balanced lung perfusion was present in the majority of patients who had complete repair of TOF/MAPCAs performed at our center.

Assessment of airway abnormalities in patients with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals.

BACKGROUND: Children with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals (TOF/MAPCAs) are at risk for post-operative respiratory complications after undergoing unifocalisation surgery. Thus, we assessed and further defined the incidence of airway abnormalities in our series of over 500 children with TOF/MAPCAs as determined by direct laryngoscopy, chest computed tomography (CT), and/or bronchoscopy. METHODS: The medical records of all patients with TOF/MAPCAs who underwent unifocalisation or pulmonary artery reconstruction surgery from March, 2002 to June, 2018 were reviewed. Anaesthesia records, peri-operative bronchoscopy, and/or chest CT reports were reviewed to assess for diagnoses of abnormal or difficult airway. Associations between chromosomal anomalies and airway abnormalities - difficult anaesthetic airway, bronchoscopy, and/or CT findings - were defined. RESULTS: Of the 564 patients with TOF/MAPCAs who underwent unifocalisation or pulmonary artery reconstruction surgery at our institution, 211 (37%) had a documented chromosome 22q11 microdeletion and 28 (5%) had a difficult airway/intubation reported at the time of surgery. Chest CT and/or peri-operative bronchoscopy were performed in 234 (41%) of these patients. Abnormalities related to malacia or compression were common. In total 35 patients had both CT and bronchoscopy within 3 months of each other, with concordant findings in 32 (91%) and partially concordant findings in the other 3. CONCLUSION: This is the largest series of detailed airway findings (direct laryngoscopy, CT, and bronchoscopy) in TOF/MAPCAS patients. Although these findings are specific to an at-risk population for airway abnormalities, they support the utility of CT and /or bronchoscopy in detecting airway abnormalities in patients with TOF/MAPCAs.

Differences in Cost of Care by Palliation Strategy for Infants With Ductal-Dependent Pulmonary Blood Flow.

BACKGROUND: In infants with ductal-dependent pulmonary blood flow, initial palliation with patent ductus arteriosus (PDA) stent or modified Blalock-Taussig (BT) shunt have comparable mortality but discrepant length of stay, procedural complication rates and reintervention burdens, which may influence cost. The relative economic impact of these palliation strategies is unknown. METHODS AND RESULTS: Retrospective study of infants with ductal-dependent pulmonary blood flow palliated with PDA stent (n=104) or BT shunt (n=251) from 2008 to 2015 at 4 centers of the Congenital Catheterization Research Collaborative. Inflation-adjusted inpatient hospital costs were calculated for first year of life using Pediatric Health Information System data. Costs derived from outpatient catheterizations not in Pediatric Health Information System were imputed. Costs were compared using propensity score-adjusted multivariable models, to account for baseline differences between groups. After propensity score adjustment, first year of life costs were significantly lower in PDA stent ($215 825 [190 644-244 333]) than BT shunt ($249 855 [230 693-270 609]) patients ( P=0.05). After addition of imputed costs, first year of life costs were not significantly different between PDA stent ($226 403 [200 274-255 941]) and BT shunt ($252 072 [232 955-272 759]) groups ( P=0.15). Patient characteristics associated with higher costs included: younger gestational age, genetic syndrome, noncardiac diagnoses, procedural complications, extracorporeal membrane oxygenation, duration of ventilation, intensive care unit and hospital length of stay and reintervention ( P≤0.02 for all). CONCLUSIONS: In this first multicenter comparative cost study of PDA stent or BT shunt as palliation for infants with ductal-dependent pulmonary blood flow, adjusted for baseline differences, PDA stent was associated with lower to equivalent costs over the first year of life. Combined with previous evidence suggesting clinical noninferiority, these findings suggest that PDA stent provides competitive health care value.

Pulmonary Pressure Assessment with the Total Artificial Heart.

Reversal of pulmonary hypertension has been observed in patients during a bridge to transplant with a left ventricular assist device. Total artificial heart (TAH) implant prevents subsequent right heart catheterization. Consequently, controversy exists over whether the prosthetic right ventricle improves or exacerbates pulmonary hypertension. A pulmonary artery (PA) pressure monitor was placed in two patients undergoing TAH implant, as a bridge to transplant. One patient had pulmonary hypertension at implant; the other had normal pulmonary pressures. Daily measurements were taken of systolic, diastolic, and mean PA pressures throughout support. Patient 1 received successful transplant after TAH support of 91 days. Systolic/diastolic (mean) PA pressures steadily decreased from 55/39 (28) mm Hg at implant to 29/18 (7) mm Hg currently. Patient 2 received support for 101 days before death due to abdominal ischemic complications. Pulmonary arterial pressures stayed consistent throughout this period, from 26/17 (20) mm Hg at implant to 23/13 (17) mm Hg at the time of death. These findings suggest that an implantable PA pressure monitor may be useful in optimizing hemodynamics and planning appropriate timing of transplant with TAH support.

Computerized tomography angiography in preoperative assessment of intravenous leiomyomatosis extending to inferior vena cava and heart.

BACKGROUND: Intravenous leiomyomatosis (IVL) extending to inferior vena cava and heart is one of the most challenging conditions for surgical treatment. We explored the use of computerized tomography angiography (CTA) in preoperative assessment for this disease. METHODS: A cohort of 31 patients with IVL extending to inferior vena cava and heart were reviewed from the year 2002 to 2014, focusing on the preoperative CTA imaging characteristics and the surgical procedures in clinical treatment. RESULTS: All patients were diagnosed correctly combining the clinical medical history and CTA imaging. Thirteen patients had tumors confined within the inferior vena cava, and 18 patients had tumors intruding into the right heart. Furthermore, 15 tumors were located in the right atrium alone, and 3 tumors involved both the right atrium and the right ventricle. All patients had simple or multiple soft tissue masses from the pelvis, with 22 tumors extending into inferior vena cava through the iliac veins and 9 tumors through the ovarian veins. Three patients had tumors invading into lung and underwent tumor thrombus resection in the pulmonary artery. Patients received either one-stage surgery or two-stage surgery dependent on patient general condition and tumor status. All operations were successfully performed by multidisciplinary cooperation, including gynecology, cardiac surgery, and vascular surgery, without severe surgical-related complications or deaths. CONCLUSIONS: CTA imaging can present location, size, and full-scale extension pathway of IVL lesions, and can be used as first-line imaging technique in preoperative assessment, having great significance in making surgical plan and obtaining successful outcome.

Haemodynamic impact of stent implantation for lateral tunnel Fontan stenosis: a patient-specific computational assessment.

BACKGROUND: The physiological importance of the lateral tunnel stenosis in the Fontan pathway for children with single ventricle physiology can be difficult to determine. The impact of the stenosis and stent implantation on total cavopulmonary connection resistance has not been characterized, and there are no clear guidelines for intervention. Methods and results A computational framework for haemodynamic assessment of stent implantation in patients with lateral tunnel stenosis was developed. Cardiac magnetic resonances images were reconstructed to obtain total cavopulmonary connection anatomies before stent implantation. Stents with 2-mm diameter increments were virtually implanted in each patient to understand the impact of stent diameter. Numerical simulations were performed in all geometries with patient-specific flow rates. Exercise conditions were simulated by doubling and tripling the lateral tunnel flow rate. The resulting total cavopulmonary connection vascular resistances were computed. A total of six patients (age: 14.4 ± 3.1 years) with lateral tunnel stenosis were included for preliminary analysis. The mean baseline resistance was 1.54 ± 1.08 WU · m(2) and dependent on the stenosis diameter. It was further exacerbated during exercise. It was observed that utilising a stent with a larger diameter lowered the resistance, but the resistance reduction diminished at larger diameters. CONCLUSIONS: Using a computational framework to assess the severity of lateral tunnel stenosis and the haemodynamic impact of stent implantation, it was observed that stenosis in the lateral tunnel pathway was associated with higher total cavopulmonary connection resistance than unobstructed pathways, which was exacerbated during exercise. Stent implantation could reduce the resistance, but the improvement was specific to the minimum diameter.

Pulmonary Hemodynamics Simulations Before Stage 2 Single Ventricle Surgery: Patient-Specific Parameter Identification and Clinical Data Assessment.

Single ventricle heart defects involve pathologies in which the heart has only one functional pumping chamber. In these conditions, treatment consists of three staged procedures. At stage 1 pulmonary flow is provided through an artificial shunt from the systemic circulation. Representative hemodynamics models able to explore different virtual surgical options can be built based on pre-operative imaging and patient data. In this context, the specification of boundary conditions is necessary to compute pressure and flow in the entire domain. However, these boundary conditions are rarely the measured variables. Moreover, to take into account the rest of the circulation outside of the three-dimensional modeled domain, a number of reduced order models exist. A simplified method is presented to iteratively, but automatically, tune reduced model parameters from hemodynamic data clinically measured before stage 2 surgery. Patient-specific local hemodynamics around the distal systemic-to-pulmonary shunt anastomosis and the connected pulmonary arteries are also analyzed. Multi-scale models of pre-stage 2 single ventricle patients are developed, including a 3D model of shunt-pulmonary connection and a number of pulmonary arteries. For each pulmonary outlet a total downstream resistance is identified, consistent with measured flow split and pressures. Target pressures such as minimum, maximum or average over one or both lungs are considered, depending on the clinical measurement. When possible, both steady and pulsatile identifications are performed. The methodology is demonstrated with six patient-specific models: the clinical target data are well-matched, except for one case where clinical data were subsequently found inconsistent. Inhomogeneous pressure, swirling blood flow patterns and very high wall shear stress 3D maps highlight similarities and differences among patients. Steady and pulsatile tuning results are similar. This work demonstrates (1) how to use routine clinical data to define boundary conditions for patient-specific 3D models in pre-stage 2 single ventricle circulations and (2) how simulations can help to check the coherence of clinical data, or provide insights to clinicians that are otherwise difficult to measure, such as in the presence of kinks. Finally, the choice of steady vs. pulsatile tuning, limitations and possible extensions of this work are discussed.