A Biomimetic Approach Utilizing Pulsatile Perfusion Generates Contractile Vascular Grafts.

Surgical implantation of decellularized cadaveric arteries is routinely used to treat right-sided congenital cardiac lesions. These acellular conduits lack the capacity for somatic growth and are prone to stenosis and calcification, necessitating multiple operations throughout childhood. Islet-1+ cardiovascular progenitor cells (CPCs) have demonstrated the capacity for differentiation into all cell types of the heart and outflow tracts.

Pediatric Surgical Pulmonary Valve Replacement Outcomes After Implementation of a Clinical Pathway.

Background: Standardization of perioperative care can reduce resource utilization while improving patient outcomes. We sought to describe our outcomes after the implementation of a perioperative clinical pathway for pediatric patients undergoing elective surgical pulmonary valve replacement and compare these results to previously published national benchmarks.

Methods: A retrospective single-center descriptive study was conducted of all pediatric patients who underwent surgical pulmonary valve replacement from 2017 through 2020, after the implementation of a clinical pathway.

Unroofed Coronary Sinus Discovered Incidentally during Cardiac Surgery: Systematic Approach to Diagnosis by Transesophageal Echocardiography.

• We report repaired URCS defect concomitant with coronary bypass surgery. • Systematic TEE was used to determine the etiology of isolated dilatation of right heart. • A diagram including the complete spectrum of URCS is provided.

Impact of transplant center volume on donor heart offer utilization rates in the United States.

Background: We tested the hypothesis that transplant centers (TCs) with higher volumes have higher donor heart (DH) offer utilization rates.

Methods: Using the Annual Data reports of the US Organ Procurement and Transplantation Network and the Scientific Registry of Transplant Recipients (SRTR) we reviewed all adult heart transplant offers between July 1, 2016 and June 29, 2019. Unadjusted donor offer utilization rates and observed to expected (O/E) DH utilization ratios adjusted using the SRTR model were calculated for each TC for all DH offers and for the following sub-categories: DH with left ventricular ejection fraction <60%, DH >40 years, DH >500 miles from TC, "hard-to-place hearts" (defined as those offered to >50 TCs) and DH designated as increased infectious risk.

Effects of universal critical CHD screening of neonates at a mid-sized California congenital cardiac surgery centre.

Introduction: CHD affects over 1 million children in the United States. Studies show decreased mortality from CHD with newborn cardiac screening. California began a screening programme on 1 July, 2013.

Novel Multidisciplinary Management of Acute Kidney Injury After Infant Orthotopic Heart Transplantation.

Acute kidney injury following orthotopic heart transplantation in pediatric recipients is often multifactorial, requiring balance of immune suppression, nephrotoxic medication exposure, nutrition, and fluid status. Therapeutic options are often limited by patient size and hemodynamic stability. We describe a four-month, 4.

Primary Transplantation for Congenital Heart Disease in the Neonatal Period: Long-term Outcomes.

Background: Primary transplantation was developed in the 1980s as an alternative therapy to palliative reconstruction of uncorrectable congenital heart disease. Although transplantation achieved more favorable results, its utilization has been limited by the availability of donor organs. This review examines the long-term outcomes of heart transplantation in neonates at our institution.

Interaction Between Ischemic Time and Donor Age on Adult Heart Transplant Outcomes in the Modern Era.

Background: We examined the effect of cold ischemic interval on modern outcomes to determine whether advances in patient management have made an impact.

Methods: Using the United Network of Organ Sharing database, we reviewed adult heart transplants between January 2000 and March 2016. We divided donor age into terciles: younger than 18 years, 18 to 33 years, and 34 years and older.

Long-term transplant outcomes of donor hearts with left ventricular dysfunction.

Objective: Despite small single-center reports demonstrating acceptable outcomes using donor hearts with left ventricular dysfunction, 19% of potential donor hearts are currently unused exclusively because of left ventricular dysfunction. We investigated modern long-term survival of transplanted donor hearts with left ventricular dysfunction using a large, diverse cohort.

Methods: Using the United Network for Organ Sharing database, we reviewed all adult heart transplants between January 2000 and March 2016.

An Absorbable Hydrogel Spray Reduces Postoperative Mediastinal Adhesions After Congenital Heart Surgery.

Background: Adhesions encountered during reoperative cardiac surgery can prolong operative time and increase operative risk. The purpose of this clinical study was to investigate the antiadhesion property of a synthetic bioabsorbable polymer spray after cardiac reoperations in infants.

Methods: A prospective randomized double-blinded study was designed.

Catheter-based endomyocardial delivery of mesenchymal precursor cells using 3D echo guidance improves cardiac function in a chronic myocardial injury ovine model.

The administration of bone marrow-derived stem cells may provide a new treatment option for patients with heart failure. Transcatheter cell injection may require multi-imaging modalities to optimize delivery. This study sought to evaluate whether endomyocardial injection of mesenchymal precursor cells (MPCs) could be guided by real-time 3D echocardiography (RT3DE) in treating chronic, postinfarction (MI) left ventricular (LV) dysfunction in sheep.

Composite scaffold provides a cell delivery platform for cardiovascular repair.

Control over cell engraftment, survival, and function remains critical for heart repair. We have established a tissue engineering platform for the delivery of human mesenchymal progenitor cells (MPCs) by a fully biological composite scaffold. Specifically, we developed a method for complete decellularization of human myocardium that leaves intact most elements of the extracellular matrix, as well as the underlying mechanical properties.

Downregulation of the CXC chemokine receptor 4/stromal cell-derived factor 1 pathway enhances myocardial neovascularization, cardiomyocyte survival, and functional recovery after myocardial infarction.

Objectives: Although adequate numbers of hematopoietic progenitor cells reside in the human bone marrow, the extent of endogenous neovascularization after myocardial infarction remains insufficient. The aim of this study was to identify the role of the CXC chemokine receptor 4/stromal cell-derived factor 1 axis in the mobilization and homing of hematopoietic progenitor cells in the ischemic heart.

Methods: Human bone marrow-derived hematopoietic progenitor cells or saline were injected systemically into athymic nude rats 48 hours after myocardial infarction.

Biodegradable fibrous scaffolds with tunable properties formed from photo-cross-linkable poly(glycerol sebacate).

It is becoming increasingly apparent that the architecture and mechanical properties of scaffolds, particularly with respect to mimicking features of natural tissues, are important for tissue engineering applications. Acrylated poly(glycerol sebacate) (Acr-PGS) is a material that can be cross-linked upon exposure to ultraviolet light, leading to networks with tunable mechanical and degradation properties through simple changes during Acr-PGS synthesis. For example, the number of acrylate functional groups on the macromer dictates the concentration of cross-links formed in the resulting network.

Naringenin inhibits neointimal hyperplasia following arterial reconstruction with interpositional vein graft.

Vessels respond to injury by a healing process that includes the development of neointima. Stenosis secondary to neointima formation is the main cause of failure following arterial reconstructions. Vessel wall homeostasis is regulated by proinflammatory cytokines that affect smooth muscle cell proliferation, growth, migration, and death.

Mesenchymal cell transplantation and myocardial remodeling after myocardial infarction.

Background: Targeted delivery of mesenchymal precursor cells (MPCs) can modify left ventricular (LV) cellular and extracellular remodeling after myocardial infarction (MI). However, whether and to what degree LV remodeling may be affected by MPC injection post-MI, and whether these effects are concentration-dependent, remain unknown.

Methods And Results: Allogeneic MPCs were expanded from sheep bone marrow, and direct intramyocardial injection was performed within the borderzone region 1 hour after MI induction (coronary ligation) in sheep at the following concentrations: 25x10(6) (25 M, n=7), 75x10(6) (75 M, n=7), 225x10(6) (225 M, n=10), 450x10(6) (450 M, n=8), and MPC free media only (MI Only, n=14).

Proliferation and migration of label-retaining cells of the kidney papilla.

The kidney papilla contains a population of cells with several characteristics of adult stem cells, including the retention of proliferation markers during long chase periods (i.e., they are label-retaining cells [LRCs]).

Challenges in cardiac tissue engineering.

Cardiac tissue engineering aims to create functional tissue constructs that can reestablish the structure and function of injured myocardium. Engineered constructs can also serve as high-fidelity models for studies of cardiac development and disease. In a general case, the biological potential of the cell-the actual "tissue engineer"-is mobilized by providing highly controllable three-dimensional environments that can mediate cell differentiation and functional assembly.

Percutaneous cell delivery into the heart using hydrogels polymerizing in situ.

Heart disease is the leading cause of death in the US. Following an acute myocardial infarction, a fibrous, noncontractile scar develops, and results in congestive heart failure in more than 500,000 patients in the US each year. Muscle regeneration and the induction of new vascular growth to treat ischemic disorders of the heart can have significant therapeutic implications.

Effect of left ventricular assist device infection on post-transplant outcomes.

Background: In this study, we sought to confirm which types of device-related infections impact bridge-to-transplant rates. We also aimed to determine the effect of device-related infections on post-transplant survival and post-transplant infection.

Methods: We retrospectively reviewed paper and electronic medical records for 149 patients undergoing left ventricular assist device (LVAD) implantation as a bridge to transplantation at the Columbia Presbyterian Medical Center between 2000 and 2006.

Allogeneic mesenchymal precursor cell therapy to limit remodeling after myocardial infarction: the effect of cell dosage.

Background: This experiment assessed the dose-dependent effect of a unique allogeneic STRO-3-positive mesenchymal precursor cell (MPC) on postinfarction left ventricular (LV) remodeling. The MPCs were administered in a manner that would simulate an off-the-self, early postinfarction, preventative approach to cardiac cell therapy in a sheep transmural myocardial infarct (MI) model.

Methods: Allogeneic MPCs were isolated from male crossbred sheep.

Biomimetic approach to tissue engineering.

The overall goal of tissue engineering is to create functional tissue grafts that can regenerate or replace our defective or worn out tissues and organs. Examples of grafts that are now in pre-clinical studies or clinical use include engineered skin, cartilage, bone, blood vessels, skeletal muscle, bladder, trachea, and myocardium. Engineered tissues are also finding applications as platforms for pharmacological and physiological studies in vitro.

Engineered microenvironments for human stem cells.

Regulation of cell differentiation and assembly remains a fundamental question in developmental biology. During development, tissues emerge from coordinated sequences of the renewal, differentiation, and assembly of stem cells. Likewise, regeneration of an adult tissue is driven by the migration and differentiation of repair cells.

Simvastatin reverses cardiac hypertrophy caused by disruption of the bradykinin 2 receptor.

Bradykinin 2 receptor (B2R) deficiency predisposes to cardiac hypertrophy and hypertension. The pathways mediating these effects are not known. Two-month-old B2R knockout (KO) and wild-type (WT) mice were assigned to 4 treatment groups (n = 12-14/group): control (vehicle); nitro-L-arginine methyl ester (L-NAME) an NO synthase inhibitor; simvastatin (SIM), an NO synthase activator; and SIM+L-NAME.