Pulmonary artery banding and arch repair versus Norwood for unbalanced atrioventricular canal defect.

BACKGROUND: The outcomes of single ventricle palliation in unbalanced atrioventricular canal defect with coarctation of aorta (uAVC+CoA) have not been well studied. These patients have a propensity to develop systemic ventricle outflow tract obstruction following aortic arch repair with pulmonary artery banding (arch-PAB); which may adversely affect survival and Fontan candidacy. METHODS: A retrospective review was performed of patients who underwent single ventricle palliation for uAVC+CoA from 2000 to 2022. Patients were divided into two groups based on initial palliation - (1) arch-PAB and (2) Norwood procedure. Demographic and clinical characteristics were analyzed and compared, along with survival data. RESULTS: 41 patients underwent stage 1 palliation for uAVC+CoA. Arch-PAB was performed in 14 infants and Norwood in 27 infants. Arch-PAB patients had more chromosomal abnormalities (28.6 vs 7.4%, p<0.009) and less severe systemic ventricle outflow tract obstruction on baseline echocardiogram (0.0 vs. 70.4%, p<0.001). Survival to stage 3 palliation was lower for the arch-PAB group (28.6 vs. 66.6%, p=0.02). Arch-PAB remained a significant risk factor for mortality (HR 2.93 [CI 1.05-8.53], p=0.04) after adjusting for chromosomal abnormalities and atrioventricular valve regurgitation. Following arch-PAB, systemic ventricle outflow tract obstruction was diagnosed in 13/14 patients. Echocardiography underestimated the degree of outflow tract obstruction in 10/13 arch-PAB patients. CONCLUSIONS: Arch-PAB has worse outcomes than Norwood for uAVC+CoA. Almost all patients develop systemic ventricle outflow tract obstruction following arch-PAB. Outflow tract obstruction is underestimated by echocardiogram, and requires a high index of suspicion along with advanced imaging to ensure timely diagnosis and management.

Neonatal heart transplantation in the United States: Trends and outcomes.

BACKGROUND: Heart transplantation in the neonatal period is associated with excellent survival. However, outcomes data are scant and have been obtained primarily from two single-center reports within the United States. We sought to analyze the outcomes of all neonatal heart transplants performed in the United States using the United Network for Organ Sharing (UNOS) dataset. METHODS: The UNOS dataset was queried for patients who underwent infant heart transplantation from 1987 to 2021. Patients were divided into two groups based on age - neonates (<=31 days), and older infants (32 days-365 days). Demographic and clinical characteristics were analyzed and compared, along with follow up survival data. RESULTS: Overall, 474 newborns have undergone heart transplantation in the United States since 1987. Freedom from death or re-transplantation for neonates was 63.5%, 58.8% and 51.6% at 5, 10, and 20 years, respectively. Patients in the newborn group had lower unadjusted survival compared to older infants (p < .001), but conditional 1-year survival was higher in neonates (p = .03). On multivariable analysis, there was no significant difference in survival between the two age groups (p = .43). Black race, congenital heart disease diagnosis, earlier surgical era, and preoperative mechanical circulatory support use were associated with lower survival among infant transplants (p < .05). CONCLUSIONS: Neonatal heart transplantation is associated with favorable long-term clinical outcomes. Neonates do not have a significant survival advantage over older infants. Widespread applicability is limited by the small number of available donors. Efforts to expand the donor pool to include non-standard donor populations ought to be considered.

Mitral Valve Replacement in Infants and Children: Five-Year Outcomes of the HALO Clinical Trial.

BACKGROUND: Repair is preferable for children with mitral valve disease, but mitral valve replacement (MVR) is occasionally necessary. This report presents the results of a multiinstitutional Investigational Device Exemption trial of the 15-mm St Jude (SJM) mechanical mitral valve (Abbott Structural Heart). METHODS: From May 2015 to March 2017, 23 children aged 0.4 to 27.4 months (mean, 7.8 months; 85% <1 year) weighing 2.9 to 10.9 kg (mean, 5.5 kg) at 15 centers underwent MVR with a 15-mm SJM mechanical mitral valve (intraannular, 45%; supraannular, 55%). A total of 21 (91%) of the children had undergone previous cardiac operations. Follow-up until death, valve explantation, or 5 years postoperatively was 100% complete. RESULTS: There were 6 deaths, all in the first 12 months; no death was valve related. Four patients required a pacemaker (2 supraannular, 2 intraannular). Three patients had thrombosis requiring valve explantation at 13, 21, and 35 days postoperatively. Two of these 3 patients were receiving low-molecular-weight heparin for anticoagulation, and the third had factor V Leiden deficiency. There were 5 nonfatal bleeding complications within 4 months of MVR (1-year freedom from bleeding, 71.0%). The 1- and 5-year freedom from death or valve explantation was 71.0%. CONCLUSIONS: In small children with severe mitral valve disease requiring MVR, the 15-mm SJM mechanical mitral valve provides satisfactory hemodynamics. Mortality and complications in these patients are not trivial. Low-molecular-weight heparin likely should be avoided as primary anticoagulation. Eventual valve replacement is inevitable.

Impact of prolonged ischemic time on pediatric heart transplantation outcomes: Improved outcomes in the most recent era.

BACKGROUND: Impacts of ischemic time (IT) on pediatric heart transplant outcomes are multifactorial. We aimed to analyze the effect of prolonged IT on graft loss after pediatric heart transplantation. We hypothesized that graft survival with prolonged IT has improved across eras. METHODS: Patients <18 years old in the Pediatric Heart Transplant Society database were included (N=6,765) and stratified by diagnosis and era (1993-2004, 2005-2009, and 2010-2019). Severe graft failure (SGF) was defined as death, retransplant, or need for mechanical circulatory support in the first 7 days post-transplant. Descriptive statistical methods were used to compare differences between patient characteristics and IT. Kaplan-Meier survival analysis compared freedom from graft loss, rejection, and infection. Multivariable analysis was performed for graft loss and SGF (hazard and logistic regression modeling, respectively). RESULTS: Diagnoses were cardiomyopathy (N = 3,246) and congenital heart disease (CHD; N = 3,305). CHD were younger, more likely to have an IT ≥4.5 hours, and more likely to require extracorporeal membrane oxygenation or mechanical ventilation at transplant (all p < 0.001). Median IT was 3.6 hours (interquartile range 2.98-4.31; range 0-10.5). IT was associated with early graft loss (HR 1.012, 95% CI 1.005-1.019), but not when analyzed only in the most recent era. IT was associated with SGF (OR 1.016 95%CI 1.003-1.030). CONCLUSIONS: Donor IT was independently associated with an increased risk of graft loss, albeit with a small effect relative to other risk factors. Graft survival with prolonged IT has improved in the most recent era but the risk of SGF persists.

Long-term Outcomes After Surgical Intervention for Congenital Supravalvar Aortic Stenosis in Children.

BACKGROUND: Primary supravalvar aortic stenosis (SVAS) is a rare congenital cardiovascular condition that can coexist with Williams-Beuren syndrome, coronary artery involvement, aortic coarctation, and pulmonary artery stenosis. SVAS repair can be achieved with low perioperative mortality, but long-term survival remains less well understood. We used the Pediatric Cardiac Care Consortium, a multicenter United States-based registry for pediatric cardiac operations, to assess long-term outcomes after SVAS repair. METHODS: We used Kaplan-Meier plots and Cox proportional hazards regression to examine factors associated with postdischarge deaths. These included sex, age-group, weight z-score, coexisting conditions (Williams-Beuren syndrome, coronary artery involvement, coarctation, and pulmonary artery stenosis), surgical techniques, and era, defined as early (1982-1995) or late (1996-2003). Survival was assessed by matching with the National Death Index through 2021. RESULTS: Of 333 patients who met inclusion criteria, 313 (94.0%) survived to discharge and 188 (60.1%) had identifiers for National Death Index matching. Over a median follow-up of 25.2 years (interquartile range, 21.1-29.4 years), 17 deaths occurred. The 30-year survival after discharge from SVAS repair was 88.7% (95% CI, 82.9%-94.8%). Infantile surgery and non-Williams-Beuren syndrome were associated with decreased 30-year survival. From the various repairs, the 2-sinus technique had better outcomes compared with all other types, except the 3-sinus technique (nonsignificant difference). Adjusted analysis revealed infantile age and type of repair as associated with postdischarge probability of death. CONCLUSIONS: These data demonstrate favorable long-term outcomes after SVAS repair, except for the infantile group that was associated with more diffuse arteriopathy. As techniques continue to evolve, future studies are warranted to investigate their long-term outcomes.

Long-term Outcomes After Interrupted Aortic Arch Repair.

BACKGROUND: Interrupted aortic arch (IAA) is associated with left ventricular outflow tract obstruction (LVOTO) and DiGeorge syndrome. High-risk infantile surgery is required to address IAA, with limited data available on long-term outcomes. We used the Pediatric Cardiac Care Consortium, a multicenter US-based registry for pediatric cardiac interventions, to assess long-term outcomes after IAA repair by patient characteristics and surgical approach. METHODS: This is a retrospective cohort study of patients undergoing IAA repair between 1982 and 2003. Kaplan-Meier plots and Cox proportional hazards regression were used to examine associations with postdischarge deaths tracked by matching with the US National Death Index. RESULTS: Of 390 patients meeting inclusion criteria, 309 (79.2%) survived to discharge. During a median follow-up of 23.6 years, 30-year survival reached 80.7% for patients surviving hospital discharge after initial IAA repair. Adjusted analysis revealed higher risk of death for type B vs type A (adjusted hazard ratio [aHR], 3.32; 95% CI, 1.48-7.44), staged repair (aHR, 2.50; 95% CI, 1.14-5.50), and LVOTO interventions during initial hospitalization (aHR, 4.12; 95% CI, 1.83-9.27) but not for LVOTO without need for interventions or presence of DiGeorge syndrome. There was a trend toward improved in-hospital and long-term survival over time during the study period. CONCLUSIONS: Staged repair, type B IAA, and need for LVOTO intervention during initial hospitalization for repair are associated with high risk of death out to 30 years. Survival outcomes are improving, but further efforts need to minimize staged approach and risks associated with LVOTO relief procedures.