Pulmonary reperfusion injury in post-palliative intervention of oligaemic cyanotic CHD: a new catastrophic consequence or just revisiting the same old story?

Pulmonary reperfusion injury is a well-recognised clinical entity in the setting pulmonary artery angioplasty for pulmonary artery stenosis or chronic thromboembolic disease, but not much is known about this complication in post-palliative intervention of oligaemic cyanotic CHD. The pathophysiology of pulmonary reperfusion injury in this population consists of both ischaemic and reperfusion injury, mainly resulting in oxidative stress from reactive oxygen species generation, followed by endothelial dysfunction, and cytokine storm that may induce multiple organ dysfunction. Other mechanisms of pulmonary reperfusion injury are "no-reflow" phenomenon, overcirculation from high pressure in pulmonary artery, and increased left ventricular end-diastolic pressure. Chronic hypoxia in cyanotic CHD eventually depletes endogenous antioxidant and increased the risk of pulmonary reperfusion injury, thus becoming a concern for palliative interventions in the oligaemic subgroup. The incidence of pulmonary reperfusion injury varies depending on multifactors. Despite its inconsistence occurrence, pulmonary reperfusion injury does occur and may lead to morbidity and mortality in this population. The current management of pulmonary reperfusion injury is supportive therapy to prevent deterioration of lung injury. Therefore, a general consensus on pulmonary reperfusion injury is necessary for the diagnosis and management of this complication as well as further studies to establish the use of novel and potential therapies for pulmonary reperfusion injury.

Novel Diabolo Configuration of a Large Covered Stent to Treat Cyanosis Related to Pulmonary Arteriovenous Malformations.

Microvascular pulmonary arteriovenous malformations (pAVMs) can lead to profound hypoxemia. "Hepatic factor" is postulated to play a role in their development. Certain patients with congenital heart disease are at particular risk to develop pAVMs, including those with heterotaxy syndromes and complex Fontan palliation. Ideally, an underlying cause is identified and corrected, although pAVMs may persist despite those interventions. We report a patient with heterotaxy syndrome s/p Fontan who had pAVMs that persisted despite Fontan revision with equal hepatic flow to both lungs. We employed a novel method to produce a diabolo configuration of a large covered stent to restrict lung flow while maintaining the potential for future dilation.

Comparison of thromboelastographic profiles in pediatric patients with congenital heart disease according to existence of cyanosis.

PURPOSE: Congenital heart disease (CHD) is divided into two groups according to cyanosis status. Cyanotic CHD has a low level of systemic oxygenation and is accompanied by increased erythropoiesis. We hypothesized that pediatric patients with CHD would exhibit different thromboelastographic profiles according to their cyanosis status. METHODS: The study recruited 70 pediatric patients younger than 12 months who were undergoing surgery for CHD. Patients were allocated to the acyanotic group or cyanotic group after preoperative evaluations of their diagnosis and peripheral oxygen saturation in the operating room on room air. After inducing anesthesia, blood samples were collected. Hematologic and thromboelastographic profiles were evaluated. RESULTS: Demographic data were similar between groups. The thromboelastographic profiles did not differ significantly between the groups. Hematologic profiles generally did not significantly differ between groups, except hematocrit (Hct) was higher in the cyanotic group (41.7 ± 6.8% vs. 35.3 ± 5.3%, p < 0.001). In patients under 3 months of age, prothrombin time (PT) (cyanotic group 15.4 ± 1.1 s vs. acyanotic group 14.2 ± 2.4 s, p = 0.02) and international normalized ratio (INR) (cyanotic group 1.24 ± 0.12 vs. acyanotic group 1.12 ± 0.27, p = 0.01) were significantly greater in the cyanotic group. CONCLUSION: There were no differences in thromboelastographic profiles between the patients with or without cyanosis, regardless of age. The Hct was higher in the cyanotic group in patients under 12 months, while the PT was prolonged and the INR was increased in the cyanotic group in patients under 3 months.

Comparison of Management Strategies for Neonates With Symptomatic Tetralogy of Fallot.

BACKGROUND: Neonates with tetralogy of Fallot and symptomatic cyanosis (sTOF) require early intervention. OBJECTIVES: This study sought to perform a balanced multicenter comparison of staged repair (SR) (initial palliation [IP] and subsequent complete repair [CR]) versus primary repair (PR) treatment strategies. METHODS: Consecutive neonates with sTOF who underwent IP or PR at ≤30 days of age from 2005 to 2017 were retrospectively reviewed from the Congenital Cardiac Research Collaborative. The primary outcome was death. Secondary outcomes included component (IP, CR, PR) and cumulative (SR): hospital and intensive care unit lengths of stay; durations of cardiopulmonary bypass, anesthesia, ventilation, and inotrope use; and complication and reintervention rates. Outcomes were compared using propensity score adjustment. RESULTS: The cohort consisted of 342 patients who underwent SR (IP: surgical, n = 256; transcatheter, n = 86) and 230 patients who underwent PR. Pre-procedural ventilation, prematurity, DiGeorge syndrome, and pulmonary atresia were more common in the SR group (p ≤0.01). The observed risk of death was not different between the groups (10.2% vs 7.4%; p = 0.25) at median 4.3 years. After adjustment, the hazard of death remained similar between groups (hazard ratio: 0.82; 95% confidence interval: 0.49 to 1.38; p = 0.456), but it favored SR during early follow-up (<4 months; p = 0.041). Secondary outcomes favored the SR group in component analysis, whereas they largely favored PR in cumulative analysis. Reintervention risk was higher in the SR group (p = 0.002). CONCLUSIONS: In this multicenter comparison of SR or PR for management of neonates with sTOF, adjusted for patient-related factors, early mortality and neonatal morbidity were lower in the SR group, but cumulative morbidity and reinterventions favored the PR group, findings suggesting potential benefits to each strategy.

Critical Cyanosis in a Neonate With Unusual Congenital Tricuspid Valve Lesion.

We describe a case of a low birth weight neonate who presented on second day of life with progressive cyanosis and oxygen saturation of 60% by pulse oximetry. The echocardiography examination revealed a large tumor-like mass connected to the tricuspid valve, with severe obstruction of the right ventricular inflow and massive right-to-left shunt through the distended foramen ovale. A large vegetation-like lesion with calcifications was discovered intraoperatively and was debrided by shave excision technique under deep hypothermic circulatory arrest. Follow-up showed normal function of the tricuspid valve and preserved biventricular function.

Transposition of the Great Arteries Associated With Non-Kommerell Diverticulum: Lessons From Two Cases.

Vascular ring malformations usually occur as an isolated lesion. d-Transposition of the great arteries (d-TGA) associated with vascular ring malformations has seldom been reported in the literature. In this report, we describe two unusual cases of d-TGA associated with non-Kommerell diverticulum resulting in vascular ring. Our approach for the diagnosis and surgical management of this unusual combination of congenital heart lesions is described.

ED50 of Intranasal Dexmedetomidine Sedation for Transthoracic Echocardiography in Children with or without a History of Cardiac Surgery for Cyanotic Congenital Heart Disease.

METHODS: This prospective single-blinded clinical trial included 72 ASA I-II stage children aged 1-36 months with cCHD who were scheduled to undergo TTE under sedation. Children were assigned to group A (n = 37) with a previous history of cardiac surgery and group B (n = 35) with no history of cardiac surgery. Doses of intranasal DEX were analyzed by up-down sequential allocation at an initial dose of 2.3 µg/kg and an increase in steps of 0.2 µg/kg. Intranasal DEXED50 values were analyzed by the up-and-down method of Dixon-Massey and probit regression to determine ED50 and 95% confidence interval (CI) for sedation. The time to effective sedation, time to regaining consciousness, vital signs, oxygen saturation, time of performing TTE, clinical adverse effects, and characteristics of regaining consciousness were compared between the two groups. RESULTS: ED50 of intranasal DEX sedation was 2.530 µg/kg (95% CI, 1.657-4.156) in group A and 2.500 µg/kg (95% CI, 1.987-3.013) in group B. There was no significant difference in sedation onset time and time to regaining consciousness between the two groups. Additionally, no significant adverse hemodynamic or hypoxemic effect was observed. There was no significant difference in sedation-onset time and wake-up time between the two groups (15 ± 4 min vs.16 ± 5 min; 50 ± 11 min vs.48 ± 10 min). This trial is registered with the China Clinical Trials Registry (ChiCTR-IOR-1800015038). CONCLUSIONS: ED50 of intranasal DEX sedation for TTE is similar in children with and without a history of cardiac surgery for cCHD.

[Effect of sodium acetate Ringer injection on perioperative fluid therapy in children with cyanotic congenital heart disease].

OBJECTIVE: To evaluate the efficacy of volume therapy with sodium acetate Ringer solution during the perioperative period in children with cyanotic congenital heart disease (CHD). METHODS: The children who underwent elective surgery for cyanotic CHD admitted to Shanghai Children's Medical Center Affiliated to the Medical School of Shanghai Jiaotong University from September to December 2018 were divided into three groups according to random number table with the informed consent of their legal representatives. All of the children received volume therapy with infusion of sodium acetate Ringer solution intravenously upon anesthesia induction. The volume of infusion was calculated according to the "4-2-1" formula (group A, the rehydration volume was 4 mL×kg-1×h-1 for the first 10 kg body weight, 2 mL×kg-1×h-1 for the second 10 kg, and 1 mL×kg-1×h-1 for the third 10 kg and above), and the volume was increased by 50% or 100% in groups B and C, respectively. The intravenous infusion lasted for 30 minutes in all the three groups. Arterial blood gas analysis was performed before and 30 minutes after infusion to observe the acid-base status and electrolyte level. Pulse oxygen saturation (SpO2), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) before and 10, 20, 30 minutes after infusion, central venous pressure (CVP) at 30 minutes after infusion were recorded, as well as adverse events occurred after infusion. RESULTS: Twenty-six children with cyanotic CHD, 17 male and 9 female, aged from 1 to 36 months, body weight 3.6 to 16.0 kg, and America Society of Anesthesiologists (ASA) level of III or IV, were enrolled in the study. The pH value in group B at 30 minutes after infusion was significantly higher than that before infusion (7.35±0.05 vs. 7.32±0.06, P < 0.05), while no significant changes were found before and after infusion in the other two groups. The hematocrits (Hct) after infusion in three groups were significantly lower than those before infusion (0.433±0.141 vs. 0.473±0.146 in group A, 0.324±0.054 vs. 0.372±0.063 in group B, 0.363±0.097 vs. 0.418±0.111 in group C, all P < 0.01), indicating that all the children in the three groups achieved effective hemodilution. However, there was no significant difference in blood gas analysis before and after infusion among the three groups. The level of blood lactic acid (Lac) in all CHD children was decreased from (1.33±0.63) mmol/L to (0.98±0.36) mmol/L after infusion of sodium acetate Ringer solution, the serum Ca2+ concentration was decreased from (1.22±0.06) mmol/L to (1.19±0.06) mmol/L, and the serum Cl- concentration was increased from (108.74±2.70) mmol/L to (109.77±2.54) mmol/L with the statistically significant differences (all P < 0.01). However, no significant difference was found in Lac or electrolyte levels before and after infusion among the three groups. There was no significant difference in vital signs before and after infusion among the three groups, but the period of infusion had an effect on SpO2 (F = 5.998, P < 0.01), HR (F = 34.279, P < 0.01) and SBP (F = 4.345, P < 0.05). HR in groups A and C were significantly lower than those before infusion, and SBP in group A was decreased gradually with the prolongation of infusion time. The CVP value at 30 minutes after infusion in group B was higher than that in group A. No adverse reactions such as rash or anaphylactic shock occurred after infusion of sodium acetate Ringer solution in all children. CONCLUSIONS: The perioperative volume therapy with sodium acetate Ringer solution in children with cyanotic CHD can effectively prevent the increase in Lac level and does not aggravate metabolic acidosis. The volume of infusion was well tolerated by all the children without disturbing the hemodynamic parameters.

Staged Palliation of Cyanotic Obstructive Lesions With a Modified Right Ventricular Outflow Procedure.

BACKGROUND: Traditional palliation for biventricular cyanotic congenital heart lesions often involves staging with systemic-to-pulmonary arterial shunts to secure pulmonary blood flow (PBF) in the newborn period prior to complete repair. However, shunts may lead to life-threatening events secondary to shunt occlusion or acute coronary steal. They may be associated with morbidity secondary to diastolic runoff, systemic steal and volume loading, and do not provide pulsatile flow which has the potential to promote pulmonary artery (PA) growth. We have alternatively performed modified right ventricular outflow (mRVO) procedures by establishing antegrade right ventricle-to-PA flow. METHODS: Retrospective review of data on all patients who underwent the mRVO procedure from 2013 to 2016, including anatomy, number of interstage catheterizations, reoperations, intensive care unit admissions, hypercyanotic episodes, interval to complete repair, and mortality. RESULTS: Seventeen nonconsecutive patients included tetralogy of Fallot (n = 14), pulmonary valve stenosis (n = 2), and 1 with pulmonary atresia-intact septum; 14 had significant branch PA stenosis. Median age of first mRVO procedure was 14 days (range 5-193), and median duration of follow-up was 15.3 months (range 4-47 months). No patients had post-palliation acute hypercyanotic episodes. Nine were admitted to the ICU for persistent interstage hypoxemia, 7 of whom required reintervention prior to complete repair, which was achieved in 11 patients. Two late deaths unrelated to mRVO occurred. CONCLUSIONS: The mRVO procedure is a potential option with satisfactory results. It avoids potential shunt-related sudden death. The physiology of the mRVO palliation may provide unique benefits by providing antegrade pulsatile PBF, facilitates catheter interventions, and avoids branch PA distortion and stenosis.

Cyanosis and Stroke due to Functional Cor Triatriatum Dexter in a Neonate.

Small remnants of the right valve of the sinus venosus are commonly found in adults, but the incidence and risk associated with these embryonic remnants in neonates are not well studied. The following report describes a cyanotic neonate with a large Eustachian valve remnant creating a functional cor triatriatum dexter who was initially diagnosed with persistent pulmonary hypertension of the newborn. The cyanosis in this infant improved over the first postnatal week with conservative management, but she suffered multifocal subcortical stroke, likely related to her intracardiac shunt. The clinical presentation and questions regarding long-term management of this rare diagnosis are explored.

A rare cause of cyanosis in newborns: arteriovenous fistula between the right pulmonary artery and the left atrium and its treatment.

The formation of a fistula between the right pulmonary artery and the left atrium via a sac is a very rare cyanotic congenital cardiopulmonary defect. A fistula between the pulmonary artery and left atrium may cause cardiac failure in utero. It can safely be treated surgically and in selected cases closure can be performed with transcatheter insertion of a device. In this article, we present a case with a fistula between the right pulmonary artery and the left atrium that was considered unsuitable for transcatheter closure and was safely treated surgically.

The blalock and taussig shunt revisited.

The systemic to pulmonary artery shunts are done as palliative procedures for cyanotic congenital heart diseases ranging from simple tetralogy of Fallots (TOFs)/pulmonary atresia (PA) to complex univentricular hearts. They allow growth of pulmonary arteries and maintain regulated blood flow to the lungs till a proper age and body weight suitable for definitive corrective repair is reached. We have reviewed the BT shunt with its anaesthtic considerations and management of associated complications.

Hippocampal damage and memory impairment in congenital cyanotic heart disease.

Neonatal hypoxia can lead to hippocampal atrophy, which can lead, in turn, to memory impairment. To test the generalizability of this causal sequence, we examined a cohort of 41 children aged 8-16, who, having received the arterial switch operation to correct for transposition of the great arteries, had sustained significant neonatal cyanosis but were otherwise neurodevelopmentally normal. As predicted, the cohort had significant bilateral reduction of hippocampal volumes relative to the volumes of 64 normal controls. They also had significant, yet selective, impairment of episodic memory as measured by standard tests of memory, despite relatively normal levels of intelligence, academic attainment, and verbal fluency. Across the cohort, degree of memory impairment was correlated with degree of hippocampal atrophy suggesting that even as early as neonatal life no other structure can fully compensate for hippocampal injury and its special role in serving episodic long term memory. © 2017 Wiley Periodicals, Inc.

Alterations in antioxidant and oxidant status of children after on-pump surgery for cyanotic and acyanotic congenital heart diseases.

OBJECTIVE: Oxidative stress refers to an imbalance between reactive oxidative species and antioxidants. In this case-controlled, prospective, observational study, we investigated the total oxidant status, total antioxidant status, oxidative stress index, and albumin and C-reactive protein levels of children with cyanotic and acyanotic congenital heart diseases who had undergone on-pump cardiac surgery. METHOD: The study groups consisted of 60 patients with congenital heart disease, who were operated under cardiopulmonary bypass, and a control group of 30 healthy individuals. The patients were classified into two groups. Among them, one was a patient group that consisted of 30 patients with acyanotic congenital heart disease and the other group consisted of 30 patients with cyanotic congenital heart disease. In the patient groups, blood samples were collected before surgery and at one and 24 hours following surgery. In control groups, blood samples were collected once during hospital admission. RESULTS: No statistically significant differences were found between the groups in terms of baseline total oxidant status, total antioxidant status, and oxidative stress index values. Regarding the postoperative first-hour and 24-hour total oxidant status and total antioxidant status levels as well as oxidative stress index values, there were no significant differences between the groups, except for an increase in total antioxidant status levels (p=0.002) 24 hours after surgery in cyanotic patients. CONCLUSION: There was no difference between oxidative stress status of cyanotic and acyanotic congenital heart disease patients and healthy individuals. Oxidative stress status of cyanotic and acyanotic patients does not change after cardiac surgery under cardiopulmonary bypass.

Rare cause of central cyanosis: right pulmonary artery to left atrial fistula.

A fistula between the right pulmonary artery and the left atrium is a very rare cause of central cyanosis. A clinical diagnosis is often made by first excluding other common causes and then performing diagnostic catheterization. Surgical closure offers a definitive cure for this rare congenital anomaly.

Outcome following augmentation of superior cavopulmonary blood flow with an arteriovenous fistula.

BACKGROUND: Axillary or brachial arteriovenous fistulae are occasionally created to improve systemic oxygen saturation in patients with functionally univentricular circulation after superior cavopulmonary anastomosis. Different techniques of fistula construction may account for the conflicting results. We sought to determine the impact of axillary arteriovenous fistula on systemic oxygen saturation and survival before subsequent palliation or heart transplantation. METHODS: Medical records of patients who underwent a side-to-side anastomosis between an adjacent axillary artery and vein for cyanosis after superior cavopulmonary anastomosis between 1991 and 2010 were reviewed. RESULTS: The median age (n = 23) at the time of fistula creation was 54 months (4-278 months). There was no operative mortality. The median duration of fistula patency was 48 months (1-174 months). Oxygen saturation improved from 71% ± 10% preoperatively to 84% ± 4% early (P < .05) and 81% ± 4% long term after the arteriovenous fistula (P < .05). Twelve patients underwent additional surgery (total cavopulmonary anastomosis 6, partial biventricular repair 2, and heart transplantation 4) after an interval of 10 to 141 months. Six patients are alive with a patent fistula without subsequent interventions after an interval of 48 to 174 months. Two patients with spontaneous closure or device closure of the fistula are alive after an interval of 76 to 80 months without subsequent interventions. Three deaths occurred with a patent fistula without subsequent interventions after an interval of 1 to 84 months. CONCLUSIONS: Systemic oxygen saturation improved with creation of an axillary arteriovenous fistula after superior cavopulmonary anastomosis. The fistula extended the duration of this stage of palliation without precluding the option for additional palliation or heart transplantation.

Computational fluid dynamics characterization of blood flow in central aorta to pulmonary artery connections: importance of shunt angulation as a determinant of shear stress-induced thrombosis.

The central aortic shunt, consisting of a Gore-Tex (polytetrafluoroethylene) tube (graft) connecting the ascending aorta to the pulmonary artery, is a palliative operation for neonates with cyanotic congenital heart disease. These tubes often have an extended length, and therefore must be angulated to complete the connection to the posterior pulmonary arteries. Thrombosis of the graft is not uncommon and can be life-threatening. We have shown that a viscous fluid (such as blood) traversing a curve or bend in a small-caliber vessel or conduit can give rise to marked increases in wall shear stress, which is the major mechanical factor responsible for vascular thrombosis. Thus, the objective of this study was to use computational fluid dynamics to investigate whether wall shear stress (and shear rate) generated in angulated central aorta-to-pulmonary artery connections, in vivo, can be of magnitude and distribution to initiate platelet activation/aggregation, ultimately leading to thrombus formation. Anatomical features required to construct the computer-simulated blood flow pathways were verified from angiograms of central aortic shunts in patients. For the modeled central aortic shunts, we found wall shear stresses of (80-200 N/m(2)), with shear rates of (16,000-40,000/s), at sites of even modest curvature, to be high enough to cause platelet-mediated shunt thrombosis. The corresponding energy losses for the fluid transitions through the aorta-to-pulmonary connections constituted (70 %) of the incoming flow's mechanical energy. The associated velocity fields within these shunts exhibited vortices, eddies, and flow stagnation/recirculation, which are thrombogenic in nature and conducive to energy dissipation. Angulation-induced, shear stress-mediated shunt thrombosis is insensitive to aspirin therapy alone. Thus, for patients with central aortic shunts of longer length and with angulation, aspirin alone will provide insufficient protection against clotting. These patients are at risk for shunt thrombosis and significant morbidity and mortality, unless their anticoagulation regimen includes additional antiplatelet medications.

Transcatheter closure of atrial septal communication during pregnancy in women with Ebstein's anomaly of the tricuspid valve and cyanosis.

Transcatheter atrial septal defect occlusion is described in three pregnant patients with Ebstein's anomaly and exercise-induced cyanosis. Procedures took place in the second and third trimester. Careful hemodynamic testing was performed prior to permanent atrial septal occlusion to confirm the capacity of the right ventricle to accept the entirety of systemic venous return in the volume-expanded state of pregnancy. Outcomes for mother and fetus were favorable in all patients with significant reduction in maternal symptoms and resolution of cyanosis.