Coronary artery augmentation with the right subclavian artery for single coronary artery variants of dextro transposition of the great arteries treated by an arterial switch operation.

Objective: Single coronary artery variants in dextro transposition of the great arteries increase the technical demands of performing coronary translocations during the arterial switch operation (ASO). Coronary augmentation using the right subclavian artery as an interposition graft is a viable option in certain cases. The aim of this study is to describe this operative technique and review outcomes. Methods: Of 59 patients who underwent an ASO, from July 2015 to May 2021, 6 had single coronary variants in which the right subclavian artery was used as an interposition graft. Mean follow-up was 21.5 months. Results: Patients mean age and weight at the time of surgery were 7.1 ± 3.8 days and 2.84 ± 0.76 kg, respectively. Four patients had the left anterior descending coronary artery and right coronary artery coming from the left sinus and the circumflex coronary artery coming from the right sinus. One patient had a single ostium arising from the left sinus and another patient had a single ostium coming from the right sinus. All patients are alive and free of cardiac symptoms at follow-up. Conclusions: Single coronary artery variants in dextro transposition of the great arteries can pose technical challenges for coronary translocation during ASO. The augmentation of coronary buttons using a segment of the right subclavian artery is an option which should be considered in selective cases.

Preoperative Evaluation of Refugee Children With Heart Disease.

The objective of this report is to identify nutritional deficiencies and health concerns in Canadian paediatric refugee patients with heart disease before cardiac surgery. A retrospective case study was conducted with 4 refugee children, aged 0-18 years, with heart disease referred to Cardiac Surgery. A total of 75% of patients had low vitamin D levels, 50% had selenium deficiency, 50% had iron deficiency anaemia, 75% were below the third percentile for height and weight for age, and 75% had dental caries. Early laboratory, nutritional, and dental screening of paediatric refugee patients at the time of heart disease diagnosis can optimize general and cardiovascular health before surgical intervention.

Notre étude visait à dépister des carences nutritionnelles et des problèmes de santé présents chez les enfants réfugiés au Canada atteints de cardiopathie, avant une intervention chirurgicale cardiaque. Une étude de cas rétrospective a été menée auprès de quatre enfants réfugiés, âgés de 0 à 18 ans, souffrant de cardiopathie et orientés vers la chirurgie cardiaque. Au total, 75 % des patients présentaient un faible taux de vitamine D, 50 % avaient une carence en sélénium, 50 % souffraient d'anémie ferriprive, 75 % avaient une taille et un poids inférieurs au troisième percentile pour leur âge et 75 % présentaient des caries dentaires. Un dépistage précoce comprenant des analyses de laboratoire, une évaluation nutritionnelle et un examen dentaire, au moment d'un diagnostic de cardiopathie chez les enfants réfugiés, pourrait permettre d'améliorer leur état de santé général et cardiovasculaire avant une intervention chirurgicale.

Hybridizing the hybrid: a "serendipitous bridge" to heart transplantation in a child with hypoplastic left heart syndrome.

We report a unique experience with stage 1 palliation of hypoplastic left heart syndrome (HLHS) using the hybrid approach. The tortuous anatomy of the ductus arteriosus precluded stenting. Persistent ductal patency and ability to support the systemic circulation adequately after prolonged prostaglandin E1 (PGE1) infusion and its subsequent discontinuation presented us with a novel approach to hybrid palliation of hypoplastic left heart syndrome. Our experience offers a tempting approach, but it should not be considered a standard alternative management option to stage I hybrid palliation based on a single case report. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12055-020-01088-8.

Tricuspid Intervention Following Pulmonary Valve Replacement in Adults With Congenital Heart Disease.

BACKGROUND: Tricuspid regurgitation (TR) is common among adults with corrected tetralogy of Fallot (TOF) or pulmonary stenosis (PS) referred for pulmonary valve replacement (PVR). Yet, combined valve surgery remains controversial. OBJECTIVES: This study sought to evaluate the impact of concomitant tricuspid valve intervention (TVI) on post-operative TR, length of hospital stay, and on a composite endpoint consisting of 7 early adverse events (death, reintervention, cardiac electronic device implantation, infection, thromboembolic event, hemodialysis, and readmission). METHODS: The national Canadian cohort enrolled 542 patients with TOF or PS and mild to severe TR who underwent isolated PVR (66.8%) or PVR+TVI (33.2%). Outcomes were abstracted from charts and compared between groups using multivariable logistic and negative binomial regression. RESULTS: Median age at reintervention was 35.3 years. Regardless of surgery type, TR decreased by at least 1 echocardiographic grade in 35.4%, 66.9%, and 92.8% of patients with pre-operative mild, moderate, and severe insufficiency. In multivariable analyses, PVR+TVI was associated with an additional 2.3-fold reduction in TR grade (odds ratio [OR]: 0.44; 95% confidence interval [CI]: 0.25 to 0.77) without an increase in early adverse events (OR: 0.85; 95% CI: 0.46 to 1.57) or hospitalization time (incidence rate ratio: 1.17; 95% CI: 0.93 to 1.46). Pre-operative TR severity and presence of transvalvular leads independently predicted post-operative TR. In contrast, early adverse events were strongly associated with atrial tachyarrhythmia, extracardiac arteriopathy, and a high body mass index. CONCLUSIONS: In patients with TOF or PS and significant TR, concomitant TVI is safe and results in better early tricuspid valve competence than isolated PVR.

Are Blood Products Routinely Required in Pediatric Heart Surgery?

A restrictive blood transfusion strategy has emerged in adult cardiac surgery. However, the feasibility in children is poorly investigated. 352 consecutive patients undergoing open-heart surgery were retrospectively reviewed, excluding patients requiring extracorporeal membrane oxygenation. Patient demographics, perioperative blood product usage, and clinical outcome parameters were investigated. Variables predicting the need for blood products were delineated. Of the 352 study patients, 148 patients (42%) underwent bloodless surgery and 204 (58%) were transfused. Of the 204 transfused patients, 170 (83.4%) patients received one blood transfusion and 34 (16.6%) received two or more blood transfusions. Patient's weight and preoperative hematocrit (Hct) were statistically significant in predicting the need for blood priming the CPB circuit (AUC 0.99, p < 0.001, sensitivity 96.6%, specificity 95.2%). A body weight of 8.5 kg carried a sensitivity of 100% and specificity of 94.5% (p < 0.001) for a blood prime. Among patients with a weight less than 8.5 kg (n = 171), only 27 patients (15.8%, p < 0.001) required additional transfusion of PRBCs. Factors impacting the need for a blood transfusion during CPB included redo surgery [odds ratio (OR) 4.61, p = 0.001] and the highest lactate level on CPB (OR 1.65, p = 0.006). Redo surgery had the highest impact (OR 7.27, p = 0.012) for requiring a postoperative PRBC transfusion. A restrictive transfusion strategy can be safely implemented in pediatric cardiac surgery. The majority of children with a BW > 8.5 kg required no blood products and those with a BW ≤ 8.5 kg required only 1 unit of blood, to prime the cardiopulmonary bypass circuit.

Aortic Arch Homograft Reconstruction of Nonconfluent Pulmonary Arteries During Extracardiac Fontan.

Reconstruction of nonconfluent pulmonary arteries during Fontan completion is a challenging technical issue. In this case report, we describe the use of an aortic homograft, including the aortic arch, to complete a Fontan and reconstruct the pulmonary artery confluence in a child with discontinuous pulmonary arteries and bilateral superior caval veins who had undergone bilateral unidirectional Glenn palliation. The configuration of the aortic homograft was ideal to ensure laminar flow from the inferior vena cava to both pulmonary arteries and in maintaining durable elastance posterior to the native aorta.

Jellyfish-Like Accessory Mitral Valve Tissue Causing Near-Collapse in a Young Child.

Accessory mitral valve tissue (AMVT) causing left ventricular outflow tract obstruction (LVOTO) is rare. We report a case of AMVT causing severe LVOTO resulting in acutely progressive symptoms of near-collapse. Urgent surgical resection eliminated the patient's life-threatening symptoms. AMVT should be considered among potential LVOTO diagnoses, and early surgical intervention may be required.

Hybrid stenting for left ventricular outflow tract obstruction in congenitally corrected transposition of the great arteries.

Congenitally corrected transposition of the great arteries is commonly associated with left ventricular outflow tract obstruction. We describe a case of congenitally corrected transposition of the great arteries and previous surgical ventricular septal defect repair with recurrent left ventricular outflow tract obstruction. The patient underwent a hybrid procedure to stent the left ventricular outflow tract, which was successful with no re-intervention through 3 years of follow-up.

Should early extubation be the goal for children after congenital cardiac surgery?

OBJECTIVE: We sought to determine the feasibility and assess the clinical outcomes associated with an early extubation strategy for all children undergoing congenital heart surgery, including neonates (age, <30 days). METHODS: We performed a linked database analysis of all patients undergoing congenital heart surgery from July 1, 2010 to December 31, 2012. We collected data on the cardiac diagnoses, preoperative status, procedure, and postoperative course, including the duration of invasive and noninvasive ventilation, failure of extubation, hemodynamic data, length of stay, complications, and mortality. A multivariable model was used to assess the independent factors associated with an inability to extubate within the operating room and with delayed extubation (>24 hours). RESULTS: We operated on 613 children, including 97 neonates. Intraoperative extubation was achieved in 71% of the cases and early extubation (≤ 24 hours) was achieved in 89% of the cases. The overall mortality was 1.5% (9 of 613 patients). Early extubation was associated with lower mortality (1% vs 9%, P < .001) and a lower rate of reintubation (4% vs 23%, P < .001) compared with delayed extubation. Notably, 63% of the neonates were extubated within 24 hours, including 67% of arterial switch operations and 54% of total anomalous pulmonary venous return repairs. Norwood operations were the only procedure in which no patient was extubated within the first 24 hours. Multivariable logistic regression demonstrated that the predictors of delayed extubation included preoperative mechanical ventilation, weight < 5 kg, a longer procedure time, and the need for postoperative inotrope support. Implementation of an early extubation strategy was associated with low rates of complications (5.1 per 10 procedures), short lengths of intensive care unit stay (median, 1 day; interquartile range, 1-3), and short hospital stays (median, 4 days; interquartile range, 3-6). CONCLUSIONS: Most children undergoing congenital heart surgery can be extubated in the operating room. Most neonates, including many undergoing complex procedures, can be extubated within the first 24 hours after surgery. Early extubation was associated with low morbidity rates and short lengths of intensive care unit and hospital stays.

Nonuniform and variable arrangements of ryanodine receptors within mammalian ventricular couplons.

RATIONALE: Single-tilt tomograms of the dyads in rat ventricular myocytes indicated that type 2 ryanodine receptors (RYR2s) were not positioned in a well-ordered array. Furthermore, the orientation and packing strategy of purified type 1 ryanodine receptors in lipid bilayers is determined by the free Mg2+ concentration. These observations led us to test the hypothesis that RYR2s within the mammalian dyad have multiple and complex arrangements. OBJECTIVES: To determine the arrangement of RYR2 tetramers in the dyads of mammalian cardiomyocytes and the effects of physiologically and pathologically relevant factors on this arrangement. METHODS AND RESULTS: We used dual-tilt electron tomography to produce en-face views of dyads, enabling a direct examination of RYR2 distribution and arrangement. Rat hearts fixed in situ; isolated rat cardiomyocytes permeabilized, incubated with 1 mmol/L Mg2+, and then fixed; and sections of human ventricle, all showed that the tetramer packing within a dyad was nonuniform containing a mix of checkerboard and side-by-side arrangements, as well as isolated tetramers. Both phosphorylation and 0.1 mmol/L Mg2+ moved the tetramers into a predominantly checkerboard configuration, whereas the 4 mmol/L Mg2+ induced a dense side-by-side arrangement. These changes occurred within 10 minutes of application of the stimuli. CONCLUSIONS: The arrangement of RYR2 tetramers within the mammalian dyad is neither uniform nor static. We hypothesize that this is characteristic of the dyad in vivo and may provide a mechanism for modulating the open probabilities of the individual tetramers.

Infant repair of massive aortic aneurysm with prosthetic valved conduit.

A 4-month-old child with severe infantile Marfan syndrome underwent successful repair of an extremely dilated aortic root and severe aortic valve insufficiency using a prosthetic valved conduit.

Nitric oxide delivery during cardiopulmonary bypass reduces postoperative morbidity in children--a randomized trial.

OBJECTIVE: Cardiac surgery requiring cardiopulmonary bypass and cardioplegic arrest leads to myocardial ischemic and reperfusion injury. Gaseous nitric oxide has been demonstrated to have a myocardial protective effect following ischemia-reperfusion. We hypothesized that gaseous nitric oxide administered during cardiopulmonary bypass would have similar beneficial effects. METHODS: In a prospective, randomized, blinded, placebo-controlled study, children undergoing repair of tetralogy of Fallot received either 20 ppm of gaseous nitric oxide or placebo delivered to the membrane oxygenator during cardiopulmonary bypass. RESULTS: A total of 16 children were randomized into 2 equal groups once their parents or guardians had given written informed consent. No differences were found in age, crossclamp time, cardiopulmonary bypass time, or methemoglobin between the 2 groups. The group receiving gaseous nitric oxide had a significantly shortened duration of mechanical ventilation (8.4 ± 7.6 vs 16.3 ± 6.5 hours; P < .05) and intensive care unit length of stay (53.8 ± 19.7 vs 79.4 ± 37.7 hours; P < .05) compared with the placebo group. The patients had significantly lower troponin levels at 12, 24, and 48 hours (P < .05) and lower B-type natriuretic peptide levels at 12 and 24 hours (P < .05). A trend was found toward a less positive fluid balance, with significantly less diuretic usage. The study patients had a greater mean hemoglobin at 48 hours, despite the absence of differences in chest tube output, packed red blood cell transfusion, platelet counts or transfusion requirements, fresh frozen plasma transfusion, or prothrombin time/partial thromboplastin time in the first 48 hours. CONCLUSIONS: The delivery of gaseous nitric oxide to the cardiopulmonary bypass circuit for children undergoing cardiac surgery results in myocardial protection, improved fluid balance, and an improved postoperative intensive care unit course.

Trends in the indications and survival in pediatric heart transplants: a 24-year single-center experience in 307 patients.

BACKGROUND: Heart transplantation is the only viable treatment for children with end-stage heart failure due to congenital heart disease (CHD) or cardiomyopathy. This study reviewed the trends in the indications for transplant and survival after transplant during the past 24 years. METHODS: A retrospective review was performed of the 307 heart transplants performed at our center since 1986. To analyze the trends in the indications for transplant as well as operative death and late-survival, the data were divided into three periods in 8-year increments: 1986 to 1993 (50 patients), 1994 to 2001 (116 patients), and 2002 to 2009 (141 patients). RESULTS: The indications for transplantation were 39% cardiomyopathy, 57% CHD, and 4% retransplant. Of the 173 with CHD, 139 (80%) had single-ventricle (SV) anomalies. In the CHD group, transplantation for failed SV palliation, including Fontan procedure, became the predominant indication in the last 8-year interval of our program. Survival after transplant was the best in patients with cardiomyopathy and the worst in patients with failed palliations for SV anomalies, including failed Fontan procedures. CONCLUSIONS: Transplantation for heart failure related to failed SV palliation has become the most common indication for patients with CHD. The high-risk nature of these transplants will have significant implications for heart transplant programs as more infants with SV anomalies survive palliative procedures performed during infancy.

Conservative management of iatrogenic esophageal perforation during neonatal cardiac surgery.

Esophageal perforation is a rare, but life threatening, entity in children. The most common iatrogenic causes include nasogastric tube insertion, stricture dilation, or endotracheal intubation. Recently, transesophageal echocardiography (TEE) has been increasingly used in pediatric cardiac surgery to assess cardiac function and structural abnormalities. The safety of TEE in children is still controversial and complications such as airway obstruction, hemodynamic compromise, and esophageal injury have been reported. We recently experienced a case of esophageal perforation caused by TEE probe insertion during neonatal cardiac surgery; two weeks of conservative management resulted in complete resolution of the injury.

Bridging children of all sizes to cardiac transplantation: the initial multicenter North American experience with the Berlin Heart EXCOR ventricular assist device.

BACKGROUND: Beginning in 2000 and accelerating in 2004, the Berlin Heart EXCOR (Berlin Heart Inc Woodlands, TX) became the first pediatric-specific ventricular assist device (VAD) applied throughout North America for children of all sizes. This retrospective study analyzed the initial Berlin Heart EXCOR pediatric experience as a bridge to transplantation. METHODS: Between June 2000 and May 2007, 97 EXCOR VADs were implanted in North America at 29 different institutions. The analysis is limited to 73 patients (75%) from 17 institutions, for which retrospective data were available. RESULTS: Median age and weight at VAD implant were 2.1 years (range, 12 days-17.8 years) and 11 kg (range, 3-87.6 kg), respectively. The primary diagnoses were dilated cardiomyopathy in 42 (58%), congenital heart disease in 19 (26%), myocarditis in 7 (10%), and other cardiomyopathies in 5 (7%). Pre-implant clinical condition was critical cardiogenic shock in 38 (52%), progressive decline in 33 (45%), or other in 2 (3%). Extracorporeal membrane oxygenation was used as a bridge to EXCOR in 22 patients (30%). Device selection was left VAD (LVAD) in 42 (57%) and biventricular assist devices (BiVAD) in 31 (43%). The EXCOR bridged 51 patients (70%) to transplant and 5 (7%) to recovery. Mortality on the EXCOR was 23% (n = 17) overall, including 35% (11 of 31) in BiVAD vs 14% (6 of 42) in LVAD patients (p = 0.003). Multivariate analysis showed younger age and BiVAD support were significant risk factors for death while on the EXCOR. CONCLUSIONS: This limited but large preliminary North American experience with the Berlin Heart EXCOR VAD as a bridge to cardiac transplantation for children of all ages and sizes points to the feasibility of this approach. The prospective investigational device evaluation trial presently underway will further characterize the safety and efficacy of the EXCOR as a bridge to pediatric cardiac transplantation.

Extracorporeal membrane oxygenation in pediatric lung transplantation.

OBJECTIVE: Effectiveness of preoperative and postoperative extracorporeal membrane oxygenation support in pediatric lung transplantation was studied. METHODS: Institutional database of pediatric lung transplants from 1990 to 2008 was reviewed. RESULTS: Three hundred forty-four patients underwent lung transplants in the study period. Thirty-three of 344 patients (9.6%) required perioperative extracorporeal membrane oxygenation support. Fifteen patients (median, age 1.3 years; range, 0.2-18 years) required 16 pretransplant extracorporeal membrane oxygenation runs. Indications were respiratory failure (8/16, 50%), severe pulmonary hypertension (5/16, 31%), and cardiopulmonary collapse (3/16, 19%). Four of these patients (27%) also required postoperative support. Six (40%) were weaned before lung transplant. Six (40%) survived to hospital discharge. Survival to discharge was higher among patients weaned before lung transplant (4/6, 66% vs 2/9, 22%). Twenty-two patients (median age, 9.4 years; range, 0.2-21 years) underwent 24 extracorporeal membrane oxygenation runs after lung transplant. Indications for postoperative support were primary graft dysfunction (18/24, 75%), pneumonia (4/24, 16%), and others (2/24, 9%). Median time between lung transplant and institution of extracorporeal membrane oxygenation was 32 hours (range, 0-1084 hours); median duration of support was 141 hours (range, 48-505 hours). Five of these patients (23%) survived to hospital discharge. Among nonsurvivors, causes of death were intractable respiratory failure (12/17, 70%) and infectious complications (4/17, 24%). CONCLUSIONS: Need for perioperative extracorporeal membrane oxygenation support is associated with significant morbidity and mortality among pediatric patients receiving lung transplants. A subset of patients who can be weaned from support preoperatively have greater likelihood of survival.