Outcomes of truncal valve replacement in neonates and infants: a meta-analysis.

BACKGROUND: Infants with truncus arteriosus typically undergo repair by repurposing the truncal valve as the neo-aortic valve and using a valved conduit homograft for the neo-pulmonary valve. In cases where the native truncal valve is too insufficient for repair, it is replaced, but this is a rare occurrence with a paucity of data, especially in the infant population. Here, we conduct a meta-analysis to better understand the outcomes of infant truncal valve replacement during the primary repair of truncus arteriosus. METHODS: We systematically reviewed PubMed, Scopus, and CINAHL for all studies reporting infant (<12 months) truncus arteriosus outcomes between 1974 and 2021. Exclusion criteria were studies which did not report truncal valve replacement outcomes separately. Data extracted included valve replacement type, mortality, and reintervention. Our primary outcome was early mortality, and our secondary outcomes were late mortality and reintervention rates. RESULTS: Sixteen studies with 41 infants who underwent truncal valve replacement were included. The truncal valve replacement types were homografts (68.8%), mechanical valves (28.1%), and bioprosthetic valves (3.1%). Overall early mortality was 49.4% (95% CI: 28.4-70.5). The pooled late mortality rate was 15.3%/year (95% CI: 5.8-40.7). The overall rate of truncal valve reintervention was 21.7%/year (95% CI: 8.4-55.7). CONCLUSIONS: Infant truncal valve replacement has poor early and late mortality as well as high rates of reintervention. Truncal valve replacement therefore remains an unsolved problem in congenital cardiac surgery. Innovations in congenital cardiac surgery, such as partial heart transplantation, are required to address this.

Recent advances in porcine cardiac xenotransplantation: from aortic valve replacement to heart transplantation.

INTRODUCTION: Cardiac xenotransplantation presents significant potential to the field of heart failure by addressing the high demand for donor organs. The availability of xenograft hearts would substantially augment the number of life-saving organs available to patients and may ultimately liberalize eligibility criteria for transplantation. AREAS COVERED: In this review, we will discuss the need for cardiac xenotransplantation and the history of research and clinical practice in this field. Specifically, we address immunologic concepts and clinical lessons learned from heart valve replacement using xenogeneic tissues, the advancement of xenotransplantation using organs from genetically modified animals, and the progression of this research to the first-in-man pig-to-human heart transplantation. EXPERT OPINION: Cardiac xenotransplantation holds tremendous promise, but the indications for this new treatment in adults will need to be clearly defined because mechanical support with ventricular assist devices and total artificial hearts are increasingly successful alternatives in heart failure. Cardiac xenotransplantation will also serve as temporary bridge to allotransplantation in babies with complex congenital heart disease who are too small for the currently available mechanical assist devices and total artificial hearts. Moreover, xenotransplantation of the part of the heart containing a heart valve could deliver growing heart valve implants for babies with severe heart valve dysfunction.

Nine-Year Experience With the Arterial Switch Operation With Closed Coronary Transfer.

BACKGROUND: Coronary artery transfer is a critical step of the arterial switch operation (ASO) for transposition of the great arteries (TGA). Strategies for coronary transfer include open transfer before neoaortic anastomosis and closed transfer after neoaortic anastomosis. This study reports outcomes of ASO with closed coronary transfer at a single institution. METHODS: A retrospective analysis was performed of patients undergoing ASO for TGA from November 2006 to September 2015. Closed coronary transfer was universally employed. Patients were assigned to simple vs complex coronary anatomy groups. The primary outcome was overall survival. Secondary outcomes included reoperation-free survival, coronary reintervention, and aortic insufficiency. RESULTS: Ninety-six consecutive patients underwent ASO for TGA. Median follow-up was 5.8 years. Thirty-five (36%) patients had complex coronary anatomy, which was associated with significantly longer cardiopulmonary bypass and aortic cross-clamp time. Overall survival was 97.4%, and reoperation-free survival was 83.6%. There was no difference in survival or reoperation-free survival of patients with simple vs complex coronary anatomy. Hispanic ethnicity, side-by-side great arteries, and urgent or emergent operation were significantly associated with the composite outcome of reoperation or mortality. There were no coronary interventions after ASO, and the incidence of moderate or greater aortic insufficiency was 2.1% at hospital discharge and 1.5% in follow-up. CONCLUSIONS: Closed coronary transfer during ASO has excellent short-term and midterm results. Despite variable and often complex coronary anatomy, coronary ischemic events after ASO are avoidable. Closed coronary transfer has a low risk of aortic valve injury or insufficiency.

Pentalogy of Cantrell With a Left Ventricular Diverticulum and Muscular VSD.

Pentalogy of Cantrell (POC) is a rare congenital disorder characterized by defects of the anterior diaphragm, midline supraumbilical abdominal wall, diaphragmatic pericardium, lower sternum, and heart. The low incidence and significant heterogeneity of POC make it difficult for most surgeons to gain consistent experience in treating these congenital heart defects. Here, we describe the treatment of a patient with POC, tetralogy of Fallot, left ventricular diverticulum, and a muscular ventricular septal defect. An innovative approach through a left ventricular diverticulotomy was utilized, which provided excellent exposure for repair of the muscular ventricular septal defect.

Surgical techniques for aortic valve xenotransplantation.

BACKGROUND: Heart valve replacement in neonates and infants is one of the remaining unsolved problems in cardiac surgery because conventional valve prostheses do not grow with the children. Similarly, heart valve replacement in children and young adults with contraindications to anticoagulation remains an unsolved problem because mechanical valves are thrombogenic and bioprosthetic valves are prone to early degeneration. Therefore, there is an urgent clinical need for growing heart valve replacements that are durable without the need for anticoagulation. METHODS: A human cadaver model was used to develop surgical techniques for aortic valve xenotransplantation. RESULTS: Aortic valve xenotransplantation is technically feasible. Subcoronary implantation of the valve avoids the need for a root replacement. CONCLUSION: Aortic valve xenotransplantation is promising because the development of GTKO.hCD46.hTBM transgenic pigs has brought xenotransplantation within clinical reach.

Immune Privilege of Heart Valves.

Immune privilege is an evolutionary adaptation that protects vital tissues with limited regenerative capacity from collateral damage by the immune response. Classical examples include the anterior chamber of the eye and the brain. More recently, the placenta, testes and articular cartilage were found to have similar immune privilege. What all of these tissues have in common is their vital function for evolutionary fitness and a limited regenerative capacity. Immune privilege is clinically relevant, because corneal transplantation and meniscal transplantation do not require immunosuppression. The heart valves also serve a vital function and have limited regenerative capacity after damage. Moreover, experimental and clinical evidence from heart valve transplantation suggests that the heart valves are spared from alloimmune injury. Here we review this evidence and propose the concept of heart valves as immune privileged sites. This concept has important clinical implications for heart valve transplantation.

Neonatal heart transplant outcomes: A single institutional experience.

OBJECTIVE: Neonatal orthotopic heart transplantation was introduced in the 1980s as a treatment for complex congenital heart disease. Progress in single-ventricle palliation and biventricular correction has resulted in a decline in neonatal heart transplant volume. However, limited reports on neonatal heart transplants have demonstrated favorable outcomes. We report the long-term outcomes of patients with neonatal heart transplants at our institution spanning nearly 30 years. METHODS: A retrospective analysis of neonatal heart transplants and neonates listed for transplant was performed at Children's Hospital Colorado. Primary outcomes were early and late survival. Secondary outcomes were rejection episodes, retransplantation, and development of cardiac allograft vasculopathy or post-transplant lymphoproliferative disease. RESULTS: A total of 21 neonates underwent orthotopic heart transplantation at our institution. Among these, 10 neonates were transplanted from 1991 to 2000, 8 neonates were transplanted from 2001 to 2010, and 3 neonates were transplanted from 2011 to 2020. The average age of these patients was 17 days, and the average weight was 3.43 kg. Early survival was 95.2%. Survival at 1 and 5 years was 85.7% (confidence interval [CI], 61.9%-95.2%) and 75% (CI, 45.6%-85.5%), respectively. Of eligible patients, the 10-year and 20-year survival was 72.2% (CI, 45.1%-85.3%) and 50% (CI, 25.9%-70.1%), respectively. CONCLUSIONS: Our institution reports favorable outcomes of neonatal heart transplantation. These results should be considered within the context of outcomes for patients awaiting transplant and the limited donor availability. However, the successful nature of these procedures suggest it may be necessary to reevaluate the indications for neonatal heart transplantation, particularly where risk of mortality and morbidity with palliative or corrective surgery is high.

Cardiac hemi-autotransplantation as a new approach to resect complex left atrial neoplasms.

Here, we describe cardiac hemi-autotransplantation as a novel technique to mobilize the heart substantially, facilitating resection of complex left atrial paraganglioma with negative margins in a young patient.

Aortic Aneurysm Eroding into the Spine.

Aortic aneurysms are usually asymptomatic until catastrophic rupture occurs. Ruptured abdominal aortic aneurysms classically present with acute back pain, shock, and a pulsatile abdominal mass. The natural history of some aortic aneurysms also includes a stage of contained rupture. This occurs when extravasation of blood from the ruptured aneurysm is contained by surrounding tissues. Here, the authors report the case of a chronic contained abdominal aortic aneurysm rupture that resulted in erosion of the spine.