Functional Single Ventricle Research Articles

Two hundred and twenty-nine cases of bidirectional cavopulmonary anastomosis with and without antegrade pulmonary blood flow, a single-center experience.

Bidirectional cavopulmonary anastomosis is palliative surgical procedure for stepwise adaptation of the ventricle by time-phased relief of blood volume from the single functional ventricle. There still exists a controversial question regarding maintaining additional antegrade pulmonary blood flow. We retrospectively reviewed the surgical cases of 261 patients who underwent bidirectional cavopulmonary anastomosis in our institution from 2012 to 2022 with special regard to antegrade pulmonary blood flow as our preferred strategy. The mean age at the time of surgery was 33.1 months (range 2.9-192 months), and the mean weight was - 7.6 kg (range 3.9-38 kg). Furthermore, we divided all the patients into two groups: in group 1 (n = 182) - patients who underwent bidirectional cavopulmonary anastomosis with antegrade pulmonary blood flow, and in group 2 (n = 47) - patients without antegrade pulmonary blood flow. The mean follow-up time was 56 months (range 24-120 months). Mortality rate was 4.8 % (n = 11) in the past 10 years. Statistical difference between groups was in the following positions: group 2 had less ICU stay (p < 0.000125) and hospital stay (p < 0.017110); group 1 had a longer duration of pleural effusion (p < 0.000003) and amount of drainage output (p < 0.007), also demonstrated higher oxygen saturation (p < 0.000264) and Glenn shunt pressure (p < 0.002) after the surgery; but there was no difference in oxygen saturation after 6, 12, and 24 months; mortality in both groups has no statistic difference. Considering our experience, we take a stand on the controlled to antegrade pulmonary blood flow strategy during bidirectional cavopulmonary anastomosis.

Improving Reproducibility of Volumetric Evaluation Using Computed Tomography in Pediatric Patients with Congenital Heart Disease.

The volumetric data obtained from the cardiac CT scan of congenital heart disease patients is important for defining patient's status and making decision for proper management. The objective of this study is to evaluate the intra-observer, inter-observer, and interstudy reproducibility of left ventricular (LV) and right ventricular (RV) or functional single-ventricle (FSV) volume. And compared those between manual and using semi-automated segmentation tool. Total of 127 patients (56 female, 71 male; mean age 82.1months) underwent pediatric protocol cardiac CT from January 2020 to December 2022. The volumetric data including both end-systolic and -diastolic volume and calculated EF were derived from both conventional semiautomatic region growing algorithms (CM, TeraRecon, TeraRecon, Inc., San Mateo, CA, USA) and deep learning-based annotation program (DLS, Medilabel, Ingradient, Inc., Seoul, Republic of Korea) by three readers, who have different background knowledge or experience of radiology or image extraction before. The reproducibility was compared using intra- and inter-observer agreements. And the usability was measured using time for reconstruction and number of tests that were reconfigured before the reconfiguration time was reduced to less than 5min. Inter- and intra-observer agreements showed better agreements degrees in DLS than CM in all analyzers. The time used for reconstruction showed significantly shorter in DLS compared with CM. And significantly small numbers of tests before the reconfiguration is needed in DLS than CM. Deep learning-based annotation program can be more accurate way for measurement of volumetric data for congenital heart disease patients with better reproducibility than conventional method.

Optimal timing of bridging annuloplasty and patch augmentation for heterotaxy syndrome associated with functional single ventricles.

Although the challenging prognosis of functional single ventricles with common atrioventricular valves due to complex morphology and uncontrollable regurgitation by valvuloplasty has been highlighted, reports on when and how these extremely complicated atrioventricular valves should be repaired are few. This study investigated the timing and risk factors for valve intervention in these patients. Between April 2006 and March 2023, 40 patients with heterotaxy syndrome associated with functional single ventricles underwent surgery. Valve intervention was performed in 14 of the 40 patients with moderate or severe atrioventricular valve regurgitation. The timing of the first valve intervention varied, with four, five, three, and two patients undergoing valve intervention before the cavopulmonary shunt, simultaneously with the cavopulmonary shunt, before total cavopulmonary connection, and simultaneously with total cavopulmonary connection, respectively. Mechanical valve replacements were performed in three patients. Among the 14 patients undergoing valve intervention, four died. Three of the four patients underwent valvuloplasty before the cavopulmonary shunt, including two who could undergo the cavopulmonary shunt but died after the procedure. Eight of the fourteen patients completed total cavopulmonary connection. The cumulative survival rate was not significantly different between the 14 patients who underwent and 26 who did not undergo intervention (hazard ratio, 2.52; 95% confidence interval, 0.56-11.24; P = 0.23). Our surgical strategies provide a chance for the next staged repair of common atrioventricular valves in patients with both heterotaxy and valvular regurgitation. Including patch augmentation, advanced valve intervention is possible at or after the cavopulmonary shunt.

Experience of Performing Systemic-to-Pulmonary Artery Shunt in Patients with Univentricular Heart Physiology and Depleted Pulmonary Blood Flow

Among patients with congenital heart disease diagnosed in infancy, 7.7% of infants have anatomical variants with functional single ventricle physiology which is often accompanied by depleted pulmonary blood flow. The type of these defects is clinically associated with cyanosis, in most cases caused not by mixing of blood at the level of the heart chambers, but by the presence of ductal-dependent pulmonary blood flow, which requires urgent surgical intervention. The aim. To evaluate the immediate and long-term outcomes of hemodynamic correction in patients with single-ventricle heart physiology with depleted pulmonary blood flow. Materials and methods. In the period from 2010 to 2022, 114 patients with reduced pulmonary blood flow underwent systemic-pulmonary anastomosis at the National Amosov Institute of Cardiovascular Surgery of the National Academy of Medical Sciences of Ukraine. Among these, 64 patients had biventricular circulation and subsequently underwent radical correction. The other 50 patients had single-ventricular heart physiology and underwent placement of systemic-pulmonary anastomosis as the first stage of the hemodynamic strategy according to Fontaine, so their data became the main material of this study. Results. Hospital mortality after systemic-pulmonary anastomosis was 8% (4 patients). An uncomplicated course of the early postoperative period was observed in 38 (76%) patients, and 16 complications were observed in the remaining 12 (24%) patients. The median follow-up period was 40 [3; 160] months. During the follow-up period, 2 (4.3%) patients died due to anastomosis thrombosis as a result of self-discontinuation of anticoagulant therapy, 3 (6.5%) patients were lost to follow-up and did not come for examination. The second stage of hemodynamic correction in the form of bidirectional cavopulmonary anastomosis was performed in 41 (82%) patients of the study group. Conclusions. Patients with single-ventricular heart physiology with depleted pulmonary blood flow are a group of extremely complex children who require an individual approach at all stages of hemodynamic correction, and early diagnosis and palliative systemic-pulmonary anastomosis continues to be a reliable alternative for these children, despite the fact that mortality after the first stage remains quite high.

The utility of novel STE parameters in echocardiographic assessment of single ventricle after Fontan palliation

Background and aims of the study A functionally single ventricle (FSV) refers to a group of congenital heart defects that are not amenable for biventricular correction. The Fontan operation is utilized as surgical treatment for most of FSV patients. The evaluation of FSV function is extremely difficult due to its unique pathophysiology. This study aimed to explore the efficacy of speckle tracking echocardiography (STE) parameters measured at rest and during exercise for comprehensive assessment of univentricular heart. MethodsWe enrolled 37 patients with a functionally single ventricle after the Fontan operation, hospitalized in the Department of Congenital Heart Defects between years 2019 and 2021.The echocardiographic stress tests were performed in the Echocardiography Laboratory of the Congenital Heart Defects Department. The study was conducted on a bicycle ergometer in a semi-recumbent position. The parameters obtained by speckle tracking echocardiography (STE): the longitudinal strain of the FSV free wall (Ɛ) and the longitudinal strain of myocardial layers: subendocardial, medial and subepicardial were analyzed. A transmural longitudinal strain gradient (TG) was calculated as the difference between longitudinal deformation of the subendocardial and subepicardial layers. Current results of cardiac magnetic resonance imaging (CMR) and cardio-pulmonary test (CPET) were also incorporated. Demographic data, past interventions, pharmacological treatment and comorbidities were extracted from medical records. ResultsƐ at rest and during exercise were not related to the parameters of physical capacity obtained on CPET nor to the CMR results. The transmural strain gradient was dependent on physical performance parameter- peak oxygen uptake- and related to the FSV ejection fraction calculated by magnetic resonance imaging. ConclusionsThe transmural strain gradient and FSV free wall strain are readily measurable and suitable for evaluating single ventricle function. The TG is positively correlated with peak oxygen uptake during the cardiopulmonary test and with the ejection fraction derived from cardiac magnetic resonance imaging. The applicability of these findings in patients undergoing the Fontan procedure warrants further exploration.

Electrophysiological characteristics of tachyarrhythmia and effects of catheter ablation in patients with Fontan circulation

Abstract Introduction Incidence of arrhythmia in complex congenital heart disease is higher than general population. Characteristics of arrhythmia in patients with functional single ventricle is not known. Methods Total 18 patients (age, 22.1 8.5 years, 9 men) with Fontan circulation who had undergone catheter ablation for tachyarrhythmia were retrospectively consecutively included. Characteristics of congenital heart disease, mechanisms of tachyarrhythmia, and efficacy and safety of catheter ablation were analyzed. Results Congenital heart diseases of the patients were as follows: double outlet right ventricle, 9; common atrioventricular septal defect, 5; and pulmonary atresia, 4. Fontan types were as follows: lateral tunnel Fontan, 9; extracardiac conduit Fontan 9. Fontan conduit puncture was successful in all patients. Mechanisms of tachyarrhythmia were as follows: intraatrial macroreentrant tachycardia, 8; focal atrial tachycardia, 4; atrioventricular nodal reentrant tachycardia, 3; twin atrioventricular nodal reciprocating tachycardia, 2; unknown, 2. Success rate of catheter ablation, recurrence rate, and complication rate were 16 of 18 patients, 2 of 18 patients, and 0 of 18 patients, respectively. Conclusion Intraatrial macroreentrant tachycardia is the most common tachycardia mechanism in patients with Fontan circulation. Catheter ablation for tachyarrhythmia is effective and safe in these population.

Serial cardiopulmonary exercise testing in young patients after one-and-half ventricle repair and Fontan procedure: a comparative study.

The Fontan procedure is the palliative surgical treatment for different congenital heart diseases (CHD) with a univentricular heart, but it has been associated with decreased exercise capacity, cardiovascular morbidity, and premature mortality. The one-and-half ventricle repair (1.5VR) was introduced as an alternative to the Fontan procedure, specifically for selected patients with borderline hypoplastic right ventricle (HRV), aiming for a more physiological circulation. Despite these efforts, the benefit of 1.5VR over Fontan circulation comparison on clinical and functional outcomes remains unclear. The aim of this study was to investigate and compare young patients with HRV after 1.5VR with those with functional single right or left ventricles (FSRV or FSLV) after Fontan palliation over a 10-year follow-up period. In this retrospective observational study, serial cardiopulmonary exercise tests (CPETs) performed in patients with 1.5VR and Fontan circulation between September 2002 and March 2024 have been analyzed. Only patients with at least 10 years of follow-up were considered. A total of 41 patients were included (age at baseline 8.6±2.6 years): 21 with FSLV, 12 with FSRV, and 10 with 1.5VR. No differences in cardiorespiratory fitness and efficiency were shown at the first CPET assessment among the three groups. At 10-year follow-up, 1.5VR had higher cardiorespiratory fitness and efficiency compared to FSLV and FSRV patients. These findings suggest that the 1.5VR may provide superior long-term functional outcomes than the Fontan procedure in patients with borderline HRV. Further studies are needed to evaluate the impact on hard clinical endpoints.

A VERY COMPLEX CASE OF DORV TYPE FALLOT: A CASE REPORT

Abstract Double outlet right ventricle (DORV) is a rare CHD characterized by ventriculoarterial connection in which both great arteries arise entirely or predominantly from the right ventricle. Its prevalence is 0.9% of all CHDs. Several chromosomal abnormalities have been associated with DORV, including trisomy 13, trisomy 18, and chromosome 22q11 deletion. Hearts with DORV are an extremely heterogeneous group showing various morphological features, connections, and relationships at each level of the cardiac segments and intersegmental junctions. As a consequence, the clinical manifestations and required surgical procedures for patients with DORV are variable. The anatomical spectrum is higly variable: it can be associated with ventricular septal defect, transposition of the great arteries (TGA) and functional single ventricle. We report the case of an infant with prenatal diagnosis of CHD and finding partial duplication of the short arm of the X chromosome. Pregnant woman at 22 weeks comes to the outpatient clinic to perform follow–up ultrasound. At that site finding of CHD which was later confirmed at birth and therefore prostaglandin therapy was started. Echocardiogram showed a wide DIV from malalignment with antero–cephalic deviation of the conal septum with significant aortic destroposition configuring picture of double outlet right ventricle. It also presents a complex right efflux obstruction already at subvalvular pulmonary departure. The pulmonary valve presented dysplastic, with en dome motion, hypoplastic. Pulmonary perfusion appears to be provided predominantly by the Botallo‘s duct originating from the isthmic region of the aorta and leading with a long and tortuous course to the pulmonary confluence near the left pulmnary artery with high velocity flow. The remaining findings are normal. Therefore, in view of the clinical picture, he was subjected to palliative surgery of right systemic–pulmonary shunt between the brachiocephalic trunk and right pulmonary artery (modified Blalock–Taussing surgery) in 3.5mm PTFE and ligation of Botallo‘s duct. At subsequent follow–up, the systemic–pulmonary shunt appeared pervious with regular flow. Wide DIV from anterior malalignment with aorta cavalier to DIV. Severe stenosis at complex pulmonary outflow with max gradient up to 124mmHg with dynamic and valvular component. For the subsequent course of treatment, the patient will be discussed collegially.

Patient-specific closed-loop model of the fontan circulation: Calibration and validation

The Fontan circulation, designed for managing patients with a single functional ventricle, presents challenges in long-term outcomes. Computational methods offer potential solutions, yet their application in cardiology practice remains largely unexplored. Our aim was to assess the ability of a patient-specific, closed-loop, reduced-order blood flow model to simulate pulsatile blood flow in the Fontan circulation. Using one-dimensional models, we simulated the aorta, superior and inferior venae cavae, and right and left pulmonary arteries, while lumping heart chambers and remaining vessels into zero-dimensional models. The model was calibrated with patient-specific haemodynamic data from combined cardiac catheterisation and magnetic resonance exams, using a novel physics-based stepwise methodology involving simpler open-loop models. Testing on a 10-year-old, anesthetised patient, demonstrated the model's capability to replicate pulsatile pressure and flow in the larger vessels and ventricular pressure. Average relative errors in mean pressure and flow were 2.9 % and 3.6 %, with average relative point-to-point errors (RPPE) in pressure and flow at 5.2 % and 16.0 %. Comparing simulation results to measurements, mean aortic pressure and flow values were 50.7 vs. 50.4 mmHg and 41.6 vs. 41.9 ml/s, respectively, while ventricular pressure values were 28.7 vs. 27.4 mmHg. The model accurately described time-varying ventricular volume with a RPPE of 2.9 %, with mean, minimum, and maximum ventricular volume values for simulation results vs. measurements at 59.2 vs. 58.2 ml, 38.0 vs. 37.6 ml, and 76.0 vs. 74.4 ml, respectively. It provided physiologically realistic predictions of haemodynamic changes from pulmonary vasodilation and atrial fenestration opening. The new model and calibration methodology are freely available, offering a platform to virtually investigate the Fontan circulation's response to clinical interventions and explore potential mechanisms of Fontan failure. Future efforts will concentrate on broadening the model's applicability to a wider range of patient populations and clinical scenarios, as well as testing its effectiveness.

(1247) - A Single Institutional Experience of Heart Transplantation in Children with Functional Single Ventricle

(1247) - A Single Institutional Experience of Heart Transplantation in Children with Functional Single Ventricle

Cardiac magnetic resonance ventricular parameters correlate with cardiopulmonary fitness in patients with functional single ventricle.

Owing to advances in medical and surgical fields, patients with single ventricle (SV) have a greatly improved life expectancy. However, progressive functional deteriorationis observed over time, with a decrease in cardiopulmonary fitness. This study aimed to identify, in patients with SV, the association between cardiac magnetic resonance imaging (CMR) parameters and change in cardiopulmonary fitness assessed by cardiopulmonary exercise test (CPET), and if certain thresholds could anticipate a decline in aerobic fitness. Patients with an SV physiology were retrospectively screened from 2011 and 2021 in a single-centre observational study. We evaluated (1) the correlation between baseline CMR and CPET parameters,(2) the association between baseline CMR results and change in peak oxygen uptake (peak VO2), and (3) the cut-off values of end-diastolic and end-systolic volume index in patients with an impaired cardiopulmonary fitness (low peak VO2 and/or high VE/VCO2 slope). 32patients were included in the study. End-systolic volume index (r = 0.37,p = 0.03), end-diastolic volume index (r = 0.45,p = 0.01), and cardiac index (r = 0.46,p = 0.01) correlated with the VE/VCO2slope. End-systolic ventricular volume (r = -0.39,p = 0.01), end-diastolic ventricular volume (r = -0.38,p = 0.01), and cardiac output (r = -0.45,p < 0.01) inversely correlated with the peak VO2. In multivariate analysis, the cardiac index obtained from baseline CMR was inversely associated with the change in peak VO2(p < 0.01). An end-diastolic volume index > 101ml/m2 and an end-systolic volume index > 47ml/m2discriminated patients with impaired cardiopulmonary fitness. CMR parameters correlate with cardiopulmonary fitness in patients with SV and can therefore be useful for follow-up and therapeutic management of these patients.

Pulmonary Venous Index as Additional Diagnostic Criteria for Fontan Palliation

Backgroud. The results of the Fontan operation, depending on the anatomy of the pulmonary arteries, have been studied quite well. Various indices have been proposed to assess the degree of hypoplasia of the pulmonary arterial bed (Nakata, Reddy, and McGoon indexes). At the same time, an obstruction of pulmonary venous blood return may be considered as a contraindication to Fontan operation. Aim of the Study. To present an optimal method for pulmonary venous index (PVI) calculation based on computed tomography angiography (CTA) enhancement of the heart data in patients with a functional single ventricle. Materials and Methods. 63 patients with a functional single ventricle (SV) underwent CTА (Philips, Brilliance iCT) before the Fontan operation. Axial sections were reconstructed to a thickness of 0.75–3 mm using soft tissue and lung filters, followed by postprocessing of the data (Horos and OsiriX software) and construction of multiplanar and 3D images. The diagnoses were presented by various types of SV of the heart. The age of the patients ranged from 3 to 30 years (median 7 years). Comparison of PVI was carried out in patients of two groups: those who survived the intervention (n = 55 patients) and those who died (n = 8). The evaluation of the pulmonary veins (PV) and the calculation of the pulmonary venous index (PVI) were carried out based on the measurement of each pulmonary vein at 2 levels (at the level of the orifices and bifurcation). The calculation of the PVI was carried out according to the formula: the sum of the cross-sectional area of the main pulmonary veins, related to the body surface area. 3 variants of PVI calculation were compared: taking into account the values of the PV areas at the level of the orifices, the bifurcation, and the sum of the minimum areas of each of the PVs. Results. In the group of survived patients, the median PVI at the level of the PV orifices was 292 mm/m2, and in the group of deceased, it was 242 mm/m2p=0.0326; at the level of PV bifurcation in the group of survivors, it was 299 mm/m2, and in the group of dead patients, it was 281 mm/m2p=0.0776; the minimum PVI was 257 mm/m2 in the survivor group and 218 mm/m2 in the deceased group p=0.006. An ROC analysis performed to determine the critical value of the minimum PVI affecting survival after Fontan operation revealed that PVI measured taking into account the minimum dimensions of the areas of the PV is a significant risk factor for death after Fontan operation p=0.00015, with its value (cutoff) &lt;233.5 mm2/m2. Conclusion. The value of the minimum PVI can be an important morphological indicator of the state of PV blood return and serve as an additional criterion in determining indications for the Fontan operation.

Efficacy assessment of strategies for mechanical univentricular circulatory support

Univentricular palliation is performed in patients with congenital heart defects, such as single functional ventricle, hypoplasia, septal defects, valve defects, obstructive defects, etc. After the palliation, the single ventricle becomes systemic, and venae cavae are directly or indirectly connected to pulmonary arteries. Palliated patients may temporary lead a full life yet eventually need heart transplantation. Mechanical circulatory support (MCS) may be an alternative treatment for heart transplantation in patients having univentricular circulation. Personalized modeling of a biotechnical MCS system allows to forecast current and optimal system states and assess support advisability and efficacy before implanting a circulatory assist device. In this study, a mathematical model of univentricular circulation with possibility to connect a circulatory assist device is presented. An algorithm for efficacy forecast and assessment of personalized mechanical univenricular circulatory support was developed. The algorithm automatically determines circulatory model parameters based on patient’s hemodynamic data and a set of parameter templates for corresponding age groups and circulatory states. This first stage is based on genetic algorithm with model parameters used as a genotype. Criterion of obtaining personalized model parameters is a zero sum of relative deviations of patient’s hemodynamic data and simulated data after personalization given the acceptable ranges of deviations determined based on accuracy of clinical diagnostic devices. At the second stage, the developed algorithm simulates a personalized biotechnical system of mechanical univentricular circulatory support using personalized circulatory model and pressure head–flow rate characteristics of circulatory assist device. At the third stage, the algorithm assesses advisability of chosen control strategy with negative recommendation for inadvisable strategy. At the last stage, the algorithm forecasts optimal states of biotechnical system determined as sufficiently approximate to normal circulation. Verification of the developed algorithm was performed with patients’ hemodynamic data from literature. Distributions of hemodynamic parameters in simulated biotechnical systems for three patients are described along with forecast optimal states and corresponding values of control parameter for chosen methods of support. In these cases, pediatric rotary blood pump previously developed by our research group was used as circulatory assist device. Assessment of changes in biotechnical system after implantation of circulatory assist device revealed inefficacy of MCS in one of three considered patients.

Clinical Presentation and Therapy of Tricuspid Atresia and Univentricular Heart.

Although the terms "single ventricle" and "univentricular heart" are frequently used to describe a variety of complex congenital heart defects, in fact, nearly all hearts have two ventricles, although one of the two may be too small to be functional. A better term for these hearts would therefore be "functional single ventricle."

Abstract 17257: Aortopulmonary Collateral Burden in the Fontan Circulation: Longitudinal Changes and Relationship With Clinical Outcomes

Background: Aortopulmonary collaterals (APC) are a common source of volume load in patients with a Fontan circulation and their burden can be quantified by CMR. Longitudinal trends in APC flow and their relationship with outcomes have not been described. Hypothesis: Higher APC flow will be associated with worse clinical outcomes in Fontan patients. Aims: To assess longitudinal changes in APC flow in the Fontan circulation using CMR and their relationship with outcomes. Methods: Single-center retrospective analysis of Fontan patients who had at least 1 CMR with APC flow data. APC flow was estimated as the difference between aortic and systemic venous flows and also expressed as a percent of aortic flow. Primary outcome was a composite of death or heart transplantation; secondary outcomes included protein losing enteropathy, ascites, chylothorax, and hemoptysis. The baseline (time at Fontan=time 0) and trend in APC flow were estimated using a linear mixed model with a random intercept and slope for each patient. Results: Analysis included 758 CMRs from 356 patients; 123 of whom had ≥ 2 CMRs. Median age at first CMR was 14 y (IQR 10-19 y) and median CMRs per patient were 2 (range 1-12). Baseline APC flow was 0.6 (±0.5) L/min/m 2 or 17 (±10) % of aortic flow. Increasing APC flow over time correlated with increasing trend in ventricular dilation and decreasing trend in SaO 2 . Over a median follow-up of 17 years, 22 patients (6%) had the composite outcome. High baseline APC flow as well as an increasing trend in APC flow were associated with clinical outcomes including an independent association with death or heart transplantation (Table). Conclusions: APCs represent a significant hemodynamic burden in functional single ventricle hearts palliated to the Fontan circulation. Higher and increasing APC flow is associated with worse clinical outcomes. Factors contributing to APC development and whether APC occlusion results in a lasting reduction in the burden remain to be elucidated.

Association of Digoxin Use With Transplant-Free Interstage Survival in Infants Palliated With a Stage 1 Hybrid Procedure.

Background Digoxin prescription in patients with single-ventricle physiology after stage 1 palliation is associated with reduced interstage death. Prior literature has primarily included patients having undergone the Norwood procedure. We sought to determine if digoxin prescription at discharge in infants following hybrid stage 1 palliation was associated with improved transplant-free interstage survival. Methods and Results A retrospective multicenter cohort analysis was conducted using data from the National Pediatric Cardiology Quality Improvement Collaborative registry data from 2008 to 2021. Infants with functional single ventricles and aortic arch obstruction discharged home after the hybrid stage 1 palliation hospitalization were included. Patients were excluded if they had supraventricular tachycardia or conversion to Norwood operation. The primary outcome was transplant-free survival. Multivariable logistic regression analysis including a propensity score for digoxin use identified associations between digoxin use and interstage death or transplant. Of 259 included infants from 45 sites, 158 (61%) had hypoplastic left heart syndrome. Forty-nine percent had a gestational age ≤38 weeks, 18% had a birth weight <2.5 kg, and 58% had a preoperative risk factor. Of the 259 subjects, 129 (50%) were discharged on digoxin. Interstage death or transplant occurred in 30 (23%) patients in the no-digoxin group compared with 18 (14%) in the digoxin group (P=0.06). With multivariate analysis, discharge digoxin prescription was associated with a lower risk of interstage death or transplant (adjusted odds ratio, 0.48 [95% CI, 0.24-0.93]; P=0.03). Conclusions In infants with single-ventricle physiology who underwent hybrid stage 1 palliation, digoxin prescription at hospital discharge was associated with improved interstage transplant-free survival.

Contemporary outcomes for functional single ventricle with total anomalous pulmonary venous connection

ObjectiveIn 2004, we reported improved early survival for patients with functional single ventricle anatomy and total anomalous pulmonary venous connection. This study sought to discover if outcomes have been ameliorated in the contemporary era. MethodsThis was a single-center review of patients with single ventricle anatomy and total anomalous pulmonary venous connection who were admitted from 1984 to 2021. The cohort was divided into similarly sized groups by date of admission: Era 1: 1984 to 1992, Era 2: 1993 to 2007, and Era 3: 2008 to 2021. Survival was compared, and Cox proportional hazards models were used to evaluate the likelihood of mortality. ResultsWe included 190 patients with single ventricle anatomy and total anomalous pulmonary venous connection. Unbalanced atrioventricular canal defect (70%) was the most common primary diagnosis. The most common type of total anomalous pulmonary venous connection was supracardiac (49%). Approximately one-third (32%) of patients had pulmonary venous obstruction. There were no significant differences in patient characteristics across eras. Early survival after initial palliative operation improved between Eras 1 and 2, and then remained stable in Era 3. Overall survival improved from Era 1 to Eras 2 and 3 (P < .001), but not between Era 2 and 3. Survival to 10 years by Eras 1 to 3 was 15%, 51%, and 54%, respectively. The anatomic features associated with worse survival were hypoplastic left heart syndrome diagnosis (hazard ratio, 1.60; 1.04-2.57) and pulmonary venous obstruction (hazard ratio, 1.80; 1.24-2.69). ConclusionsOverall survival for patients with single ventricle anatomy and total anomalous pulmonary venous connection has plateaued since the early 2000s. Even in the most recent era, survival to age 10 years remains less than 60%. Risk factors for mortality include the diagnosis of hypoplastic left heart syndrome and pulmonary venous obstruction. Further studies should focus on identification of the pathophysiological factors underlying the increased mortality.

Long-term outcomes of functional single ventricles associated with heterotaxy syndrome†.

The goal of this study was to determine the long-term surgical outcomes of patients with functional single ventricles associated with heterotaxy syndrome, risk factors for mortality and factors associated with Fontan stage completion. Overall, 279 patients with a functional single ventricle associated with heterotaxy syndrome who underwent an initial surgical procedure at our institute between 1978 and 2021 were grouped into 4 "eras" based on the surgical year during which the initial procedure was performed: era 1 (1978-1989, n = 71), era 2 (1990-1999, n = 98), era 3 (2000-2009, n = 64) and era 4 (2010-2021, n = 46). Neonatal surgery was more frequent in eras 3 and 4 than in eras 1 and 2. Overall, 228 patients had right atrial isomerism; 120 patients (43.0%) had a total anomalous pulmonary venous connection; and 58 patients (20.8%) underwent an initial procedure as neonates. Overall survival rates at 10, 20 and 30 years after the initial procedure were 47.1%, 40.6% and 36.1%, respectively. Neonatal surgery (P < 0.001), total anomalous pulmonary venous connection repair at the initial procedure (P < 0.001) and early era (P < 0.001) were identified as risk factors for mortality, with the last 2 variables being negatively associated with Fontan stage completion (P < 0.001 for both). Although era had a favourable effect on survival, total anomalous pulmonary venous connection with intrinsic pulmonary vein obstruction was associated with both mortality and Fontan stage completion. R19092.

The role transmural strain gradient in assessment of functionally single ventricle contractility

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The funds of the Ministry of Education and Science. Background Cardiac imaging in patients with FSV (functionally single ventricle) underwent the Fontan procedure is a challenge. One of the most difficult issue to be resolved in FSV patients is myocardial contractility. Thus, we sought for deformation parameters analysis by STE (Speckle Tracing Echocardiography), for haemodynamic and structural reason. We incorporated a novel STE (Speckle Tracing Echocardiography) parameter– TG (transmural strain gradient) representing the difference in strain between subendocardial and subepicardial layer to assess FSV contractile reserve. The role of TG in assessment of FSV after Fontan palliation has not been evaluated yet. Purpose The study aimed to introduce/evaluate transmural longitudinal strain gradient (TG) at rest and during exercise as marker of FSV contractility and exercise performace. Methods The group of 37 patients with FSV after Fontan palliation were enrolled in our study at least 12 months after Fontan operation and in sinus rhythm on ECG. We performed an transthoracic echocardiography at rest and during exercise on a semi-supine cycle ergometer. The apical-chamber views were registered for subsequent post-processing analysis. Due to heterogeneous FSV morphology and primary defects as well as accompanying intraventricular septum segments malformation in majority of cases, we decided to measure and analyse FSV free wall longitudinal strain only. The values of layer-specific: subendocardial and subepicardial longitudinal free wall systolic strain were assessed and the gradient between them was calculated. The TG at rest and during exercise were compared with the cardiopulmonary exercise test results, NYHA class, FSV systolic function studied by CMR (Cardiac Magnetic Resonance) and NT-proBNP concentration. Results The values of TG at rest and during exercise correlated with peak oxygen uptake during the cardio-pulmonary exercise test (p = ,012 for TG at rest, p = ,031). TG during exercise was negatively correlated with CMR-derived ejection fraction (p = ,031) . There was no relationship between TG and NYHA-class and NT-proBNP. Conclusion(s) TG is a promising parameter for FSV contractility assessment. Our preliminary study suggests that it can complete traditional imaging technics and derived parameters. TG is highly associated to exercise capacity. However, utility of TG requires further investigation.

Sutureless Repair of Extracardiac Univentricular Total Anomalous Pulmonary Venous Connection

BackgroundThis study aimed to evaluate the results of sutureless repair of extracardiac total anomalous pulmonary venous connection (TAPVC) with a functional single ventricle at a single institution, including changes in the anastomotic site over time. MethodsThe database contained 98 patients with single-ventricle anatomy who underwent extracardiac TAPVC repair from 1996 to 2022. The median age and body weight at surgery were 59 days and 3.8 kg, respectively. Eighty-seven patients had heterotaxy syndrome, and 42 had preoperatively obstructed TAPVC. Primary sutureless repair was performed in 18 patients, 13 of whom were neonates. The cross-sectional area of the anastomotic site of the atrium and pericardium was divided by the body surface area, and the changes in this value over time were assessed. The median follow-up was 5.2 years (range, 0-19.4 years). ResultsOperative mortality and late mortality occurred in 2 (2.0%) and 38 (38.8%) patients, respectively. The actuarial survival rate at 5 years postoperatively was 56.2%. Multivariate analysis identified preoperatively obstructed TAPVC as a risk factor for mortality. Recurrent pulmonary venous stenosis (PVS) developed in 25 patients, thus giving a 5-year rate of freedom from PVS of 64.9%. Multivariate analysis revealed that sutureless repair significantly decreased the incidence of recurrent PVS. The cross-sectional anastomotic area tended to grow in accordance with the patients’ growth. ConclusionsSutureless repair of extracardiac TAPVC with univentricular anatomy achieved acceptable results. The anastomotic site tended to grow over time and contributed to a decline in the rate of recurrent PVS.