Transcriptomes and metabolism define mouse and human MAIT cell populations.

Mucosal-associated invariant T (MAIT) cells are a subset of T lymphocytes that respond to microbial metabolites. We defined MAIT cell populations in different organs and characterized the developmental pathway of mouse and human MAIT cells in the thymus using single-cell RNA sequencing and phenotypic and metabolic analyses. We showed that the predominant mouse subset, which produced IL-17 (MAIT17), and the subset that produced IFN-γ (MAIT1) had not only greatly different transcriptomes but also different metabolic states. MAIT17 cells in different organs exhibited increased lipid uptake, lipid storage, and mitochondrial potential compared with MAIT1 cells. All these properties were similar in the thymus and likely acquired there. Human MAIT cells in lung and blood were more homogeneous but still differed between tissues. Human MAIT cells had increased fatty acid uptake and lipid storage in blood and lung, similar to human CD8 T resident memory cells, but unlike mouse MAIT17 cells, they lacked increased mitochondrial potential. Although mouse and human MAIT cell transcriptomes showed similarities for immature cells in the thymus, they diverged more strikingly in the periphery. Analysis of pet store mice demonstrated decreased lung MAIT17 cells in these so-called "dirty" mice, indicative of an environmental influence on MAIT cell subsets and function.

Norwood Aneurysm: Report of a Rare Phenomenon.

An 18-year-old male with complex single-ventricle physiology status post-3-stage palliation developed a large Norwood aneurysm (77 × 67 mm). The patient underwent a successful surgical reconstruction. Care providers must be aware of this rare complication and provide appropriate surveillance.

The number of postoperative surgical or diagnostic procedures following congenital heart surgery correlates with both mortality and hospital length of stay.

BACKGROUND: Outcomes for congenital heart disease have dramatically improved over the past several decades. However, there are patients who encounter intraoperative or postoperative complications and ultimately do not survive. It was our hypothesis that the number of postoperative procedures (including surgical and unplanned diagnostic procedures) would correlate with hospital length of stay and operative mortality. METHODS: This was a retrospective review of 938 consecutive patients undergoing congenital heart surgery at a single institution over a 2-year timeframe. The number of postoperative surgical and unplanned diagnostic procedures were counted and the impact on hospital length of stay and mortality was assessed. RESULTS: 581 of the 938 (62%) patients had zero postoperative diagnostic or surgical procedures. These patients had a median length of stay of 6 days with a single operative mortality (0.2%). 357 of the 938 (38%) patients had one or more postoperative diagnostic or surgical procedures. These patients had a total of 1586 postoperative procedures. There was a significant correlation between the number of postoperative procedures and both hospital length of stay and mortality (p < .001). Patients who required 10 or more postoperative procedures had a median hospital length of stay of 89 days and had a 50% mortality. There were no survivors in patients who had 15 or more postoperative procedures. CONCLUSIONS: The data demonstrate that the number of postoperative procedures was highly correlated with both hospital length of stay and mortality.

Tetralogy of Fallot and Aortic Dissection: Implications in Management.

We present the case of a 61-year-old man with tetralogy of Fallot postrepair and mechanical aortic valve replacement with an aortic root/ascending/arch aneurysm with chronic type A aortic dissection. He underwent uncomplicated aortic root and total arch replacement. Continued surveillance for aortic aneurysm is necessary in the tetralogy of Fallot population. (Level of Difficulty: Intermediate.).

Pseudoaneurysm of Innominate Artery Graft Stump in an Infant.

Innominate artery grafts are often utilized in pediatric cardiac surgery and very rarely lead to complications, including infection. Here, we present a unique case of an infant who underwent repair of coarctation of the aorta and hypoplastic arch using a GORE-TEX graft (W. L. Gore and Associates, Newark, DE) for antegrade cerebral perfusion. The graft subsequently became infected with Pseudomonas and formed a pseudoaneurysm with resultant tracheal compression. The presentation, diagnosis, and management of this mycotic pseudoaneurysm are described.

Long-term Results Using Glutaraldehyde-treated Homograft Pericardium in Congenital Heart Surgery.

BACKGROUND: This study reports the long-term outcomes using glutaraldehyde-treated cryopreserved homograft pericardium (CPH) in neonates, infants, children, and young adults undergoing congenital cardiac surgery. METHODS: A retrospective review was performed of all patients at a single institution (Rady Children's Hospital, San Diego, CA) who had undergone surgical implantation with CPH between 2006 and 2016. The study identified 134 consecutive patients who underwent implantation of a total of 276 patches. The baseline demographic characteristics, primary cardiac diagnosis, surgical characteristics, operative reports, and postoperative catheterization and reoperation reports were analyzed. The use of CPH was categorized by specific anatomic insertion site. RESULTS: The median age at patch implantation was 1.47 years (range, 1 day to 31.6 years). The numbers and locations of patch use were 124 for pulmonary arterial repair, 57 for repair of the aorta, 49 for septal repair, and 43 at other sites. At a median follow-up of 5.29 years, 9 patients had died (6.7%), but none of those deaths were related to CPH. Twelve patients (8.96%) underwent reoperations, and 18 patients (13.4%) underwent catheter interventions at sites of CPH implantation. The 10-year freedom from patch-induced reoperation and catheter intervention rates were 88.5% and 86.9%, respectively. Overall patch failure-free survival was 85.8% and 79.0% at 5 and 10 years, respectively. CONCLUSIONS: The use of CPH patch in the surgical correction of congenital heart disease is effective and durable, as evidenced by the low reintervention rates. These results are comparable to the early and midterm outcomes of other similarly used surgical patches.

Successful Management of a Patient With Jacobsen Syndrome and Hypoplastic Left Heart Syndrome.

Jacobsen syndrome (JS) is a rare genetic condition characterized by intellectual disability, hematologic abnormalities, and congenital heart defects. A male infant presented at birth with phenotypic findings of JS and echocardiographic findings of hypoplastic left heart syndrome (HLHS). Array comparative genomic hybridization was performed at age three days and revealed an 8.1 Mb terminal deletion on the long arm of chromosome 11, consistent with JS. At five days of age, a hybrid stage 1 procedure was performed. At age 46 days, he underwent a Norwood operation followed by bidirectional Glenn at age six months. He is presently 23 months old and doing well. With careful consideration of the individual patient and comorbidities associated with JS, we propose that at least a subset of patients with JS and HLHS can do well with staged surgical palliation.

Prevalence of Complications Following Unifocalization and Pulmonary Artery Reconstruction Procedures.

BACKGROUND: Unifocalization and pulmonary artery reconstructions have been developed to treat complex disorders of pulmonary artery development. These procedures require extremely long periods of cardiopulmonary bypass (CPB) to facilitate surgical repair. The objective of this study was to document the prevalence of complications in patients undergoing unifocalization or pulmonary artery reconstructions associated with prolonged periods of CPB. METHODS: This was a retrospective review of 100 consecutive patients who underwent unifocalization (n = 66) or pulmonary artery reconstructions (n = 34) with CPB times in excess of five hours. Thirty-eight of these operations were primary procedures, whereas 62 were reoperations. RESULTS: The median age at surgery was 15 months, median duration of CPB was 473 minutes, median number of postoperative complications was 5, and the median length of hospital stay was 24 days. The most frequently encountered complications were low cardiac output (43%), open sternum (40%), reintubation (24%), arrhythmia (17%), and bronchoscopy (17%). There was a correlation between the total number of complications and overall length of hospital stay (R2 = 0.64). Major adverse cardiac events (MACE) occurred in 11 patients with one hospital mortality. Patients who experienced MACE had a median length of stay that was 35 days longer (56 vs 21 days) than patients who did not experience MACE. CONCLUSIONS: The data demonstrate that complications were relatively frequent in this cohort of patients and had a linear association with hospital length of stay. Major adverse cardiac events were encountered at a modest prevalence but had a profound impact on measures of outcome.

Arterial Switch Operation in a Patient With Ehlers-Danlos Syndrome Type IV.

Ehlers-Danlos syndrome vascular type IV is characterized by translucent skin, easy bruising, and fragility of arteries. A full-term female infant presented at four weeks of age with a diagnosis of d-transposition of the great arteries with restrictive atrial septal defect. She successfully underwent emergent balloon atrial septostomy and placement of patent ductus arteriosus (PDA) stent. She required restenting of the PDA and pulmonary artery banding prior to arterial switch procedure. At 16 months of age, the patient successfully underwent arterial switch procedure without complication. This report demonstrates the feasibility of an arterial switch operation along with long-term follow-up of this rare condition.

Aortopulmonary Window With Pulmonary Atresia and Interrupted Aortic Arch: A Very Rare Triad.

Aortopulmonary window (APW) is a rare lesion, accounting for 0.2% to 0.6% of all congenital heart diseases. We report a rare case of an infant with APW, interrupted aortic arch, and pulmonary atresia with intact interventricular septum and right ventricle-dependent coronary circulation. This report describes the anatomy of this lesion set, the complex surgical palliation that was required, and the management of postoperative complications.

Fontan Revision: Presurgical Planning Using Four-Dimensional (4D) Flow and Three-Dimensional (3D) Printing.

Pulmonary arteriovenous malformations (AVMs) can be a complication of certain postoperative Fontan patients whose hepatic venous blood return is not distributed evenly to both lungs. A ten-year-old female, who had previously undergone staged single ventricle palliation for complex congenital heart disease, underwent a Fontan revision due to significant left-sided pulmonary AVMs and increasing arterial oxygen desaturation. The combination of four-dimensional flow cardiac magnetic resonance imaging and three-dimensional printing enabled presurgical planning for a Fontan takedown and diversion of hepatic venous flow to the azygous vein that resulted in significant clinical improvement.

Non-anastomotic failure of woven Dacron tube grafts in the thoracic aorta in young adults.

BACKGROUND: Dacron tube grafts have been used in the surgical management of cardiovascular disease since the 1970s. Complications at the site of the anastomosis have been well described. Non-anastomotic failure is far less common. We present a series of four patients who presented with complications of non-anastomotic failure of woven Dacron tube grafts. METHODS: A retrospective chart review of four patients who presented to our institution between March 2014 and March 2017 with clinical complications of a Dacron tube graft was conducted. RESULTS: All four patients underwent a staged surgical repair for an interrupted aortic arch between the years of 1988 and 2001. All four patients underwent revision of their original interposition graft (Gore-Tex, W.L. Gore & Associates, Flagstaff, AZ) with implantation of a Hemashield woven Dacron tube graft (Maquet, Rastatt, Germany). From 13 to 22 years postimplant of the Dacron tube graft, all patients presented with symptoms or clinical evidence of primary graft failure. Two patients underwent urgent surgical intervention and did not survive. One patient underwent attempted surgical intervention, which was aborted in the setting of profuse bleeding, and ultimately had an endovascular rescue of the tube graft with a Zenith Alpha endograft (Cook Medical, Bloomington, IN). One patient underwent elective endovascular intervention prior to onset of symptoms. CONCLUSION: Non-anastomotic failure of woven Dacron tube grafts can occur in the thoracic aorta in young adults and may be managed with endovascular techniques.

Epicardial Intraoperative Three-Dimensional Mapping of Wolff-Parkinson-White Syndrome in a Child With Ebstein's Anomaly.

Catheter ablation of arrhythmias in small patients has inherent significant risk because of the patient, catheter, and lesion size. Heart block, perforation, and coronary damage may occur. This report shows adaptation of a three-dimensional electroanatomic mapping system for intraoperative use in a small patient with Ebstein's anomaly who was undergoing a cone procedure and a bidirectional Glenn procedure. Use of this technique gave clear identification of the epicardial insertion points of two accessory pathways causing Wolff-Parkinson-White syndrome and resistant episodes of supraventricular tachycardia. Successful three-dimensional mapping and cryoablation were performed with a short procedure time and no complications. The patient remains without preexcitation or arrhythmia 6 months postoperatively.

Per-Ventricular Insertion of Melody Valve-in-Valve in the Neoaortic Position in a Single-Ventricle Patient.

Percutaneous therapies for congenital heart disease have been evolving rapidly despite limited investment from industry. The Melody transcatheter pulmonary valve (Medtronic, Inc, Minneapolis, MN USA) replacement therapy represents an important advancement in this arena. It has been approved in the United States for use in the pulmonary position, on a Humanitarian Device Exemption status. Off-label use of the Melody transcatheter pulmonary valve has extended to the mitral, pulmonary, and aortic valves, especially in previously implanted valves with prosthetic valve degeneration. The single-ventricle patient poses additional challenges. However, there exists one report in the English literature of a patient undergoing Melody transcatheter neoaortic valve replacement after the patient developed severe neoaortic regurgitation after Fontan palliation. Here, we describe a patient with hypoplastic left heart syndrome, palliated with a Norwood modified Blalock-Taussig shunt, with a progressively regurgitant quadricusp neoaortic valve who underwent bioprosthetic valve replacement. There was early prosthetic valve degeneration after a year of bioprosthesis implantation. As he was declined for transplantation, he underwent successful per-ventricular Melody valve-in-valve replacement.