Impact of Atrioventricular Valve Intervention at Each Stage of Single Ventricle Palliation.

Background: Significant atrioventricular valve dysfunction can be associated with mortality or need for transplant in functionally univentricular heart patients undergoing staged palliation. The purposes of this study are to characterize the impact of concomitant atrioventricular valve intervention on outcomes at each stage of single ventricle palliation and to identify risk factors associated with poor outcomes in these patients. Methods: The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried for functionally univentricular heart patients undergoing single ventricle palliation from 2013 through 2022. Separate analyses were performed on cohorts corresponding to each stage of palliation (1: initial palliation; 2: superior cavopulmonary anastomosis; 3: Fontan procedure). Bivariate analysis of demographics, diagnoses, comorbidities, preoperative risk factors, operative characteristics, and outcomes with and without concomitant atrioventricular valve intervention was performed. Multiple logistic regression was used to identify predictors associated with operative mortality or major morbidity. Results: Concomitant atrioventricular valve intervention was associated with an increased risk of operative mortality or major morbidity for each cohort (cohort 1: 62% vs 46%, P < .001; cohort 2: 37% vs 19%, P < .001; cohort 3: 22% vs 14%, P < .001). Black race in cohort 1 (odds ratio [OR] 3.151, 95% CI 1.181-9.649, P = .03) and preterm birth in cohort 2 (OR 1.776, 95% CI 1.049-3.005, P = .032) were notable predictors of worse morbidity or mortality. Conclusions: Concomitant atrioventricular valve intervention is a risk factor for operative mortality or major morbidity at each stage of single ventricle palliation. Several risk factors are associated with these outcomes and may be useful in guiding decision-making.

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.

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.

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.

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.

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.

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.

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.

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%.