Support with Single Ventricle-Ventricular Assist Device (sVAD) in Patients with Functionally Univentricular Circulation Prior to Fontan Operation.

Some patients with functionally univentricular circulation develop cardiac failure refractory to maximal management and are supported with a ventricular assist device (VAD). The purpose of this manuscript is to summarize our previous publications related to single ventricle-ventricular assist device (sVAD) support in patients with functionally univentricular circulation and to describe our current institutional approach at University of Florida to sVAD support in neonates, infants, and children prior to Fontan. Our programmatic philosophy at University of Florida is to strive to identify the minority of neonates with functionally univentricular circulation who are extremely high-risk prior to initiating staged palliation and to stabilize these neonates with primary preemptive sVAD in preparation for cardiac transplantation; our rationale for this approach is related to the challenges associated with failed staged palliation and subsequent bail-out sVAD support and transplantation. A subset of extremely high-risk neonates and infants with functionally univentricular ductal-dependent circulation undergo primary preemptive sVAD insertion and subsequent cardiac transplantation. Support with VAD clearly facilitates survival on the waiting list during prolonged wait times and optimizes outcomes after Norwood (Stage 1) by providing an alternative pathway for extremely high-risk patients. Therefore, the selective utilization of sVAD in extremely high-risk neonates facilitates improved outcomes for all patients with functionally univentricular ductal-dependent circulation. At University of Florida, our programmatic approach to utilizing sVAD support as a bridge to transplantation in the minority of neonates with functionally univentricular circulation who are extremely high-risk for staged palliation is associated with Operative Mortality after Norwood (Stage 1) Operation of 2.9% (2/68) and a one-year survival of 91.1% (82/90) for all neonates presenting with hypoplastic left heart syndrome (HLHS) or HLHS-related malformation with functionally univentricular ductal-dependent systemic circulation. Meanwhile, at University of Florida, for all 82 consecutive neonates, infants, and children supported with pulsatile paracorporeal VAD: Kaplan-Meier survival estimated one year after VAD insertion = 73.3% (95% confidence interval [CI] = 64.1-83.8%), and Kaplan-Meier survival estimated five years after VAD insertion = 68.3% (95% CI = 58.4-79.8%). For all 48 consecutive neonates, infants, and children at University of Florida with biventricular circulation supported with pulsatile paracorporeal VAD: Kaplan-Meier survival estimated one year after VAD insertion = 82.7% (95% CI = 72.4-94.4%), and Kaplan-Meier survival estimated five years after VAD insertion = 79.7% (95% CI = 68.6-92.6%). For all 34 consecutive neonates, infants, and children at University of Florida with functionally univentricular circulation supported with pulsatile paracorporeal sVAD: Kaplan-Meier survival estimated one year after VAD insertion = 59.7% (95% CI = 44.9-79.5%), and Kaplan-Meier survival estimated five years after VAD insertion = 50.5% (95% CI = 35.0-73.0%). These Kaplan-Meier survival estimates for patients supported with pulsatile paracorporeal VAD are better in patients with biventricular circulation in comparison to patients with functionally univentricular circulation both one year after VAD insertion (P=0.026) and five years after VAD insertion (P=0.010). Although outcomes after VAD support in functionally univentricular patients are worse than in patients with biventricular circulation, sVAD provides a reasonable chance for survival. Ongoing research is necessary to improve the outcomes of these challenging patients, with the goal of developing strategies where outcomes after sVAD support in functionally univentricular patients are equivalent to the outcomes achieved after VAD support in patients with biventricular circulation.

Surgical management of hearts with isomeric atrial appendages.

BACKGROUND AND AIM: On the basis of previously published accounts, coupled with our own experience, we have assessed the surgical approaches to patients with isomeric atrial appendages. METHODS: We reviewed pertinent published studies on surgical treatment of individuals with isomeric atrial appendages, with the pertinent surgical details provided by most of the manuscripts. RESULTS: Half of patients with right isomerism, and two-thirds of those with left isomerism have bilateral superior caval veins. Azygos extension of the inferior caval vein is reported in three-quarters of those with left isomerism. The coronary sinus is universally absent in right isomerism, along with totally anomalous pulmonary venous connection, and is absent in two-fifths of those with left isomerism. Univentricular atrioventricular connections are expected in up to three-quarters of those with right isomerism. Atrioventricular septal defect is reported in up to four-fifths, more frequently in right isomerism, with such patients typically having discordant ventriculoatrial connections or double outlet right ventricle. Reported mortalities extend to 85% for those with right, and 50% for those with left isomerism. In right isomerism, mortality is up to 54% for systemic-to-pulmonary arterial shunting, up to 75% for univentricular repair, and up to 95% for repair of totally anomalous pulmonary venous connection itself. No more than one-quarter had undergone Fontan completion, with reported mortalities of 21%. CONCLUSION: Early surgical results are satisfactory in patients with left isomerism, but disappointing for those with right. Recent advances in cardiac and liver transplantation may offer improved survival.

Fontan failure: phenotypes, evaluation, management, and future directions.

OBJECTIVES: Management of "failing" and "failed" Fontan circulation, particularly the indications, timing, and type of re-intervention, currently remains nebulous. Factors contributing to pathogenesis and mortality following Fontan procedure differ between children and adults. METHODS: Since organ systems in individual patients are affected differently, we searched the extant literature for a "failing" and "failed" Fontan reviewing the clinical phenotypes, diagnostic modalities, pharmacological, non-pharmacological, and surgical techniques employed, and their outcomes. RESULTS: A total of 410 investigations were synthesised. Although proper candidate selection, thoughtful technical modifications, timely deployment of mechanical support devices, tissue-engineered conduits, and Fontan takedown have decreased the peri-operative mortality from 9 to 15% and 1 to 3% per cent in recent series, pernicious changes in organ function are causing long-term patient attrition. In the setting of a failed Fontan circulation, literature documents three surgical options: Fontan revision, Fontan conversion, or cardiac transplantation. The reported morbidity of 25% and mortality of 8-10% among Fontan conversion continue to improve in select institutions. While operative mortality following cardiac transplantation for Fontan failure is 30% higher than for other CHDs, there is no difference in long-term survival with actuarial 10-year survival of around 54%. Mechanical circulatory assistance, stem cells, and tissue-engineered Fontan conduit for destination therapy or as a bridge to transplantation are in infancy for failing Fontan circulation. CONCLUSIONS: An individualised management strategy according to clinical phenotypes may delay the organ damage in patients with a failing Fontan circulation. At present, cardiac transplantation remains the last stage of palliation with gradually improving outcomes.

Impact of platelet population behaviours in patients undergoing the Glenn procedure.

Pulmonary pressure is one of the most important parameters in the postoperative follow-up of patients who have undergone the Glenn procedure. Platelet activation markers, which are inexpensive and easily accessible blood count parameters, have been shown to be associated with the aetiology and pathogenesis of primary pulmonary artery hypertension. We examined the relationship between platelet activation markers and pulmonary pressures in the early postoperative period of patients who underwent the Glenn procedure.Eighty-five patients who underwent the Glenn procedure in our clinic between January 2011 and March 2020 were included in the study retrospectively. Fifty-one patients were male and 34 were female, and age varied from 4 to 416 months, with a mean of 28.64 ± 51 months.Patients with increased pulmonary blood flow on palliation before Glenn surgery had higher mean platelet volume values. However, no correlation was found between pulmonary pressures and platelet activation markers in the early postoperative period.There was not similar study evaluating platelet activation markers in the paediatric age group before and after postoperative Glenn surgery in the literature. Therefore, even if platelet activation markers provide information about the pulmonary bed, they may be misleading due to other reasons that trigger bleeding and inflammatory processes in the early postoperative period.

Pregnancy and early post-natal outcomes of fetuses with functionally univentricular heart in a low-and-middle-income country.

BACKGROUND: Care of children with functionally univentricular hearts is resource-intensive. OBJECTIVES: To analyse pregnancy and early post-natal outcomes of fetuses with functionally univentricular hearts in the setting of a low-middle-income country. METHODS: A retrospective study was conducted during the period of January 2008-October 2019. Study variables analysed included gestational age at diagnosis, maternal and fetal comorbidities and cardiac diagnosis including morphologic type of single ventricle. Outcomes analysed included pregnancy outcomes, type of post-natal care and survival status on the last follow-up. RESULTS: A total of 504 fetuses were included. Mean maternal age was 27.5 ± 4.8 years and mean gestational age at diagnosis was 25.6 ± 5.7 weeks. Pregnancy outcomes included non-continued pregnancies (54%), live births (42.7%) and loss to follow-up (3.3%). Gestational age at diagnosis was the only factor that impacted pregnancy outcomes (non-continued pregnancies 22.5 ± 3.5 vs. live births 29.7 ± 5.7 weeks; p < 0.001). Of the 215 live births, intention-to-treat was reported in 119 (55.3%) cases; of these 103 (86.6%) underwent cardiac procedures. Seventy-nine patients (36.7%) opted for comfort care. On follow-up (median 10 (1-120) months), 106 patients (21%) were alive. Parental choice of intention-to-.treat or comfort care was the only factor that impacted survival on follow-up. CONCLUSIONS: Prenatal diagnosis of functionally univentricular hearts was associated with overall low survival status on follow-up due to parental decisions on not to continue pregnancy or non-intention-to-treat after birth. Early detection of these complex defects by improved prenatal screening can enhance parental options and reduce resource impact in low-and-middle-income countries.

Incidence and Outcomes of Patients with Functionally Univentricular Heart Born in Latvia, 2007 to 2015.

Background and Objectives: A functionally univentricular heart is the term used to describe congenital heart defects where it is impossible to restore two pumping chambers. These lesions are associated with high mortality, morbidity, and medical resource utilization. The aim of this study was to review incidence and outcomes of patients with a functionally univentricular heart at the only pediatric cardiac surgery center in Latvia. Methods: We performed a retrospective review of medical records of (i) all children with a functionally univentricular heart treated at the Clinic of Pediatric Cardiology and Cardiac Surgery, and (ii) all prenatally diagnosed cases of univentricular heart at Children's Clinical University Hospital in Latvia. We reviewed data regarding children born from January 1, 2007, to December 31, 2015. The children's cardiac anatomy and interventions were categorized in accordance with the International Pediatric and Congenital Cardiac Code (v3.3). Results: During the study period, 49 patients with a functionally univentricular heart were admitted to Children's Clinical University Hospital with a corrected incidence of 0.69 per 1000 live births per year. There were 26 patients that had a hypoplastic left ventricle, and 22 patients that had a hypoplastic right ventricle, while one patient had an indeterminate ventricle. Thirty (61.2%) patients had died by the end of data collection. Twenty-one of the 30 deaths occurred before or immediately after stage I surgical palliation. Cumulative neonatal and 5-year survival of patients with a hypoplastic right ventricle was 81.8% and 63.6%, respectively; for patients with hypoplastic left ventricle-46.2% and 17.3%, respectively. Discussion: This is the first mid-term outcome study of patients with a univentricular heart in Latvia. The high mortality reflects the challenges of a small-volume, developing congenital cardiac surgery center. Data from this study will be used as a baseline for quality improvement.

Inferior and right-sided juxtaposition of the left atrial appendage with an unexpected type of inter-atrial communication.

We have re-investigated an unusual cardiac specimen with juxtaposition of the atrial appendages. The original description dates to 1962, when the autopsy was performed at the Children's Memorial Hospital in Chicago, now Ann & Robert H. Lurie Children's Hospital of Chicago. The heart was subsequently stored in the Farouk S. Idriss Cardiac Registry at the same institution. The specimen shows usual atrial arrangement, but with the morphologically left appendage juxtaposed in a rightward manner, passing behind the heart rather than through the transverse sinus so as to reach its location inferior to the morphologically right appendage. The heart also demonstrated an inter-atrial communication between the cavities of the juxtaposed left appendage and the morphologically right atrium. We provide a detailed description of the morphology, and provide images of this lesion, which to the best of our knowledge has not previously been described.

Extremely Long-Term Follow-Up of Dr William Glenn's Original Patient Cohort With Superior Cavopulmonary Anastomosis (1958-1990).

BACKGROUND: Historically, Dr William Glenn performed the first classic superior cavopulmonary anastomosis in a seven-year-old child at Yale in 1958. By 1990, this operation was performed consecutively in over 90 patients. With over 60 years of follow-up, this is the longest survival record of early Glenn patients from the first 30 years. METHODS: We performed a single center, retrospective evaluation of patients undergoing a Glenn operation. A collected list of surviving patients, previously updated in 1988, included demographics, age at procedure, and underlying diagnosis. Follow-up data were obtained in May 2022 using electronic medical records to determine survival, age of survivors, and age of deceased. RESULTS: Ninety-five patients underwent the Glenn operation from 1958 to 1990: 58.9% (n = 56) were male and 41.1% (n = 39) female. Fifteen patients were lost to follow-up, but 12 were alive in 1988. Sixty patients were deceased (68.1%), with an average age of 33.5 ± 18.3(range, 2-78, excluding seven early deaths) years. The oldest patient who passed away was a 78-year-old male with tetralogy of Fallot. Twenty patients remain alive, with an average age of 47.5 (range, 32-66) years. Four patients who are still alive today (20% survivors) are older than 60 years. CONCLUSIONS: Since Dr Glenn's original operation, the technique, timing, and indications have been modified (ie, bidirectional Glenn) to adapt to the current era. By following this initial group of patients, we can approach completion of the survival rates for adult congenital patients who were some of the first pediatric patients to receive this ground-breaking palliative procedure.

Analysis of 82 Children Supported With Pulsatile Paracorporeal Ventricular Assist Device: Comparison of Patients With Biventricular Versus Univentricular Circulation.

We reviewed outcomes in 82 consecutive children supported with the Berlin Heart pulsatile ventricular assist device (VAD), comparing those with functionally univentricular circulation (n = 34) to those with biventricular circulation (n = 48). The primary outcome was mortality. Kaplan-Meier (KM) methods and log-rank tests were used to assess group differences in long-term survival. T-tests using KM-estimated survival proportions and standard errors were used to compare groups at specific time points. 48 biventricular patients were supported (Age: median = 1.4 years, range = 17 days-17.7 years; Weight [kilograms]: median = 9.4, range = 3.1-112), including 43 BiVAD, 4 LVAD only, and 1 LVAD converted to BiVAD. In biventricular patients, duration of VAD support [days]: median = 97, range = 4-315. Of 48 biventricular patients, 35 underwent heart transplantation, 7 died on VAD, 5 weaned off VAD (1 of whom underwent heart transplantation 334 days after weaning), and 1 is still on VAD. 34 univentricular patients were supported with single VAD (sVAD) (Age: median = 38.5 days, range = 4 days-13.3 years; Weight [kilograms]: median = 3.98, range = 2.4-32.6). In univentricular patients, duration of VAD support [days]: median = 138, range = 4-554. Of 34 univentricular patients, 22 underwent transplantation, 11 died on VAD, and 1 is still on VAD. One-year survival after VAD insertion was 82.7% (95% CI = 72.4-94.4%) in biventricular patients and 59.7% (95% CI = 44.9-79.5%) in univentricular patients, p = 0.026. Five-year survival after VAD insertion was 79.7% (95% CI = 68.6-92.6%) in biventricular patients and 50.5% (95% CI = 35.0-73.0%) in univentricular patients, p = 0.010. Pulsatile VAD facilitates bridge to transplantation in neonates, infants, and children with functionally univentricular circulation; however, survival is worse than in patients with biventricular circulation.

A Single-Institutional Experience with 36 Children Smaller Than 5 Kilograms Supported with the Berlin Heart Ventricular Assist Device (VAD) over 12 Years: Comparison of Patients with Biventricular versus Functionally Univentricular Circulation.

OBJECTIVES: We reviewed outcomes in all 36 consecutive children <5 kg supported with the Berlin Heart pulsatile ventricular assist device (VAD) at the University of Florida, comparing those with univentricular circulation (n = 23) to those with biventricular circulation (n = 13). METHODS: The primary outcome was mortality. Kaplan-Meier methods and log-rank tests were used to assess group differences in long-term survival after VAD insertion. T-tests using estimated survival proportions and standard errors were used to compare groups at specific time points. RESULTS: Of all 82 patients ever supported with Berlin Heart at our institution, 49 (49/82 = 59.76%) weighed <10 kg and 36 (36/82 = 43.90%) weighed <5 kg. Of these 36 patients who weighed <5 kg, 26 (26/36 = 72.22%) were successfully bridged to transplantation. Of these 36 patients who weighed <5 kg, 13 (13/36 = 36.1%) had biventricular circulation and were supported with 12 biventricular assist devices (BiVADs) and 1 left ventricular assist device (LVAD) (Age [days]: median = 67, range = 17-212; Weight [kilograms]: median = 4.1, range = 3.1-4.9), while 23 (23/36 = 63.9%) had univentricular circulation and were supported with 23 single ventricle-ventricular assist devices (sVADs) (Age [days]: median = 25, range = 4-215; Weight [kilograms]: median = 3.4, range = 2.4-4.9). Of 13 biventricular patients who weighed <5 kg, 12 (12/23 = 92.3%) were successfully bridged to cardiac transplantation. Of 23 functionally univentricular patients who weighed <5 kg, 14 (14/23 = 60.87%) were successfully bridged to cardiac transplantation. For all 36 patients who weighed <5 kg: 1-year survival estimate after VAD insertion = 62.7% (95% confidence interval [CI] = 48.5%-81.2%) and 5-year survival estimate after VAD insertion = 58.5% (95% CI = 43.8%-78.3%). One-year survival after VAD insertion: 84.6% (95% CI = 67.1%-99.9%) in biventricular patients and 49.7% (95% CI = 32.3%-76.4%) in univentricular patients, P = 0.018. Three-year survival after VAD insertion: 84.6% (95% CI = 67.1%-99.9%) in biventricular patients and 41.4% (95% CI = 23.6%-72.5%) in univentricular patients, P = 0.005. CONCLUSION: Pulsatile VAD facilitates bridge to transplantation in neonates and infants weighing <5 kg; however, survival after VAD insertion in these small patients is less in those with univentricular circulation in comparison to those with biventricular circulation.

Implementation of Virtual Fontan Heart Camps During a Pandemic.

BACKGROUND: Children with a Fontan operation represent a unique form of congenital heart disease (CHD) that requires multiple cardiac surgeries and procedures with an uncertain long-term outcome. Given the rarity of the types of CHD that require this procedure, many children with a Fontan do not know any others like them. METHODS: With the cancelation of medically supervised heart camps due to the COVID-19 pandemic, we have organized several physician-led virtual day camps for children with a Fontan operation to connect with others in their province and across Canada. The aim of this study was to describe the implementation and evaluation of these camps via the use of an anonymous online survey immediately after the event and reminders on days 2 and 4 postevent. RESULTS: Fifty-one children have participated in at least 1 of our camps. Registration data showed that 70% of participants did not know anyone else with a Fontan. Postcamp evaluations showed that 86% to 94% learned something new about their heart and 95% to 100% felt more connected to other children like them. CONCLUSION: We have demonstrated the implementation of a virtual heart camp to expand the support network for children with a Fontan. These experiences may help to promote healthy psychosocial adjustments through inclusion and relatedness.

Which Phenotypes Should We Include in the Hypoplastic Left Heart Syndrome?

The recent special issue of the World Journal for Pediatric and Congenital Heart Surgery devoted to hypoplastic left heart syndrome, and its related anomalies, contained significant information of great clinical relevance. Very little attention, however, was devoted to the integrity of ventricular septum as providing a criterion to distinguish between the phenotypes to be included within the syndrome, as opposed to the related anomalies. In this commentary, we summarize the evidence in support of the notion that the phenotypes to be included within the syndrome can be interpreted on the basis of an acquired disease of fetal life. We suggest that it is the integrity of the ventricular septum that provided the major criterion for the distinction between the lesions making up the syndrome and the related anomalies. The subsets of lesions to be included within the syndrome can then be recognized in terms of the time, subsequent to the closure of the embryonic interventricular communication, at which the left ventricle ceased its growth relative to the remainder of the cardiac components. On this basis, it is possible to recognize the combinations of aortic and mitral atresia, mitral stenosis with aortic atresia, combined mitral and aortic stenosis, and hypoplasia of the left ventricle with commensurate hypoplasia of the aortic and mitral valves; the latter combination now recognized as the hypoplastic left heart complex.

Defining the Spectrum of Hypoplastic Left Heart Syndrome (HLHS).

The 2021 International Paediatric and Congenital Cardiac Code and the Eleventh Revision of the International Classification of Diseases provide the following definition for hypoplastic left heart syndrome (HLHS): "Hypoplastic left heart syndrome (HLHS) is defined as a spectrum of congenital cardiovascular malformations with normally aligned great arteries without a common atrioventricular junction, characterized by underdevelopment of the left heart with significant hypoplasia of the left ventricle including atresia, stenosis, or hypoplasia of the aortic or mitral valve, or both valves, and hypoplasia of the ascending aorta and aortic arch." Although HLHS with intact ventricular septum (HLHS + IVS) and HLHS with ventricular septal defect (HLHS + VSD) are different cardiac phenotypes, both of these lesions are part of the spectrum of HLHS.

Hypoplastic Left Heart Syndrome Palliation: Technical Aspects and Common Pitfalls of the Hybrid Approach.

The Giessen hybrid strategy is used for initial palliation of HLHS and variants when the intent is to pursue further staged palliative reconstruction toward Fontan circulation. It is also used for initial palliation of HLHC and other anomalies with potential for eventual biventricular repair. From June 1998 - October 2021, 197 patients with HLHS and related variants underwent hybrid stage 1. Follow-up is complete (median 8.3 [range 0-23.3] years). Operative mortality for hybrid stage I was 3.6% (7/197); reduced to 2.8% since 2010 (4/141). Interstage mortality was 4.1% (8/197). Operative mortality for comprehensive stage II was 5.8% (10/172), and since 2010 was 1.8% (2/113 patients). Fontan completion has been accomplished in 117 patients, and 33 are still awaiting stage III. Twelve patients underwent heart transplantation. Over 23 years, overall survival is 77.7% and transplant-free survival is 73.6%.

Ventricular assist device support in neonates and infants with a failing functionally univentricular circulation.

Some neonates with functionally univentricular hearts are at extremely high risk for conventional surgical palliation. Primary cardiac transplantation offers the best option for survival of these challenging neonates; however, waitlist mortality must be minimized. We have developed a comprehensive strategy for the management of neonates with functionally univentricular hearts that includes the selective use of conventional neonatal palliation in standard-risk neonates, hybrid approaches in neonates with elevated risk secondary to a noncardiac etiology, and neonatal palliation combined with insertion of a single ventricular assist device (VAD) in neonates with elevated risk secondary to a cardiac etiology. Here we describe our selection criteria, technical details, management strategies, pitfalls, and current outcomes for neonates with functionally univentricular hearts supported with a VAD. Our experience shows that extremely high-risk neonates with functionally univentricular hearts who are poor candidates for conventional palliation can be successfully stabilized with concomitant palliation and pulsatile VAD insertion while awaiting cardiac transplantation.

The Ventricular Switch: An Alternative Strategy Toward Biventricular Repair in Moderately Hypoplastic Left Ventricles or Complex Connections.

Hypoplastic left heart complex (HLHC) constitutes a spectrum of left ventricular hypoplasia and valvar disease and can be associated with increased morbidity and mortality. Traditionally, management of these lesions involves single ventricle palliation (SVP). However, the SVP may be associated with substantial long-term consequences related to its physiology. Alternative management strategies have been employed to achieve biventricular circulation. We have proposed a novel technique, termed the "ventricular switch" procedure, in which the hypoplastic or unroutable left ventricle can be harnessed to function as the subpulmonic ventricle, and the right ventricle functions as the systemic ventricle. Herein, we describe our rationale for considering biventricular circulation and the ventricular switch procedure in HLHC and in other complex lesions.

Risk analysis for patients with a functionally univentricular heart after systemic-to-pulmonary shunt placement.

OBJECTIVES: To investigate risk factors for mortality after systemic-to-pulmonary (SP) shunt procedures in patients with a functionally univentricular heart using the Japan Cardiovascular Surgery Database registry. METHODS: Clinical data from 75 domestic institutions were collected. Overall, 812 patients with a functionally univentricular heart who underwent initial SP shunt palliation were eligible for analysis. Patients with pulmonary atresia with an intact ventricular septum and patients with a SP shunt as part of the Norwood procedure were excluded. Risk factors for 30- and 90-day mortalities were analysed using a logistic regression model. RESULTS: Median age and body weight at SP shunt placement were 41 days and 3.6 kg, respectively. Modified Blalock-Taussig shunt, central shunt and other types of SP shunts were applied in 689 (84.9%), 94 (11.8%) and 30 (3.7%) patients, respectively. Cardiopulmonary bypass was utilized in 410 patients (51%) for 128 min (median, 19-561). There were 411 isolated SP shunt procedures. Median hospital stay was 27 days, and 742 (91.4%) patients were discharged. The 30- and 90-day mortality rates were 3.4% and 6.0%, respectively. Placement of a central shunt was identified as a risk factor for 30-day mortality, while lower body weight, preoperative ventilator support, right atrial isomerism and coexistence of major aortopulmonary collateral arteries and an unbalanced atrioventricular septal defect were identified as risk factors for 90-day mortality. CONCLUSIONS: SP shunt carries a high mortality rate in patients with a functionally univentricular heart when it is performed in smaller patients with complex cardiac anomalies.

Systemic Semilunar Valve Repair/Replacement With Fontan Circulation: The Mayo Clinic Experience.

Background: There is a paucity of literature regarding systemic semilunar valve (SSLV) dysfunction in patients with Fontan circulation. We sought to describe our center's 47-year experience with systemic semilunar valve replacement or repair (SSLVR) in patients with Fontan circulation. Methods: The Mayo Clinic Fontan Database is a comprehensive institutional database that stores clinical information of 1176 patients from 1973 to 2021. It was reviewed to identify patients who had a SSLV intervention at the time of or after Fontan. A cohort of 15 patients was identified and a retrospective review of their records was performed. Results: Fourteen patients had SSLV replacement (all mechanical) and one had a repair. SSLVR occurred up to 29 years following the Fontan (mean 11.3 ± 9 years, median 14 years). Thirteen of 14 with SSLVR were performed after Fontan and one was done at the time of initial Fontan. This was an older cohort and mean age at the time of Fontan was 8.7 ± 9.4 years (median 4 years). Indication for the operation was > moderate SSLV regurgitation in all patients. Six patients had decreased ventricular function (EF < 50%) prior to SSLVR and 8 had reduced function after SSLVR. Conclusion: Fortunately, the need for SSLV intervention after Fontan was rare, as evidenced by our small cohort extracted from a large single-institution database spanning a 47-year time period. Reduced preoperative and postoperative ejection fraction was common but did not seem to impact the outcome. Optimal timing for SSLV intervention after Fontan remains unclear.

Transition to Ductal Stenting for Single Ventricle Patients Led to Improved Survival: An Institutional Case Series.

BACKGROUND: The use of systemic-to-pulmonary shunts (SPS) in neonates with single ventricle heart defects and ductal-dependent pulmonary blood flow (ddPBF) was historically associated with high morbidity and mortality at our center. As a result, we transitioned to the preferential use of ductus arteriosus stents (DS) when feasible. This report describes our initial results with this strategy. METHODS: A single-center study of single ventricle patients that received DS or SPS from 2015 to 2019 was performed to assess whether DS was associated with decreased in-hospital morbidity and increased survival to stage II palliation. RESULTS: A total of 34 patients were included (DS = 11; SPS = 23). Underlying cardiac anomalies were similar between groups and included pulmonary atresia, unbalanced atrioventricular septal defect, and tricuspid atresia. Procedure success was similar between groups (82% vs 83%). Two DS patients were converted to SPS, due to ductal vasospasm or pulmonary artery obstruction, and four SPS patients required surgical shunt revision. In DS patients, postprocedure mechanical ventilation duration was shorter (one vs three days, P = .009) and fewer required postprocedure extracorporeal membrane oxygenation (9% vs 39%, P = .11). A higher proportion of DS patients survived to stage II palliation (100% vs 64%, P = .035), and the probability of one-year survival was higher in DS patients (100% vs 61%, P = .02). CONCLUSIONS: At our center, patients with single ventricle heart defects and ddPBF that received DS experienced reduced in-hospital morbidity and increased survival to stage II palliation compared to SPS.

Serial cardiovascular magnetic resonance feature tracking indicates early worsening of cardiac function in Fontan patients.

BACKGROUND: In Fontan patients, attrition of ventricular function is well recognized, but early detection of ventricular dysfunction is difficult. The aim of this study is to longitudinally assess ventricular strain in Fontan patients using a new method for cardiac magnetic resonance (CMR) feature tracking, and to investigate the relationship between ventricular strain and cardiac systolic function. METHODS AND RESULTS: In this prospective, standardized follow-up study in 51 Fontan patients, age ≥ 10 years, CMR and concomitant clinical assessment was done at the start of the study and after 2 years. CMR feature tracking was done combining the dominant and hypoplastic ventricles. Global longitudinal strain (GLS) (-17.3% versus -15.9%, P = 0.041) and global circumferential strain (GCS) (-17.7 versus -16.1, P = 0.047) decreased over 2 years' time. Ejection fraction (EF) (57%), cardiac index (CI) (2.7 l/min/m2) and NYHA functional class (97% in class I/II) were preserved. The strain values of the combined dominant and hypoplastic ventricles were significantly worse compared to those of the dominant ventricle only (GLS -16.8 (-19.5 to -14.0) versus -18.8 (-21.3 to -15.3) respectively, P = 0.001, GCS -18.3 (-22.1 to -14.8) versus -22.5 (-26.3 to -19.4) respectively, P < 0.001). CONCLUSIONS: This study showed a decrease in cardiac strain over 2 years in Fontan patients without clinical signs of Fontan failure, where EF, CI and clinical status were still preserved. Cardiac strain might be a sensitive early indicator of systolic ventricular decline. Furthermore, combined strain of the hypoplastic and dominant ventricles seems a more accurate representation of cardiac strain in functionally univentricular hearts.