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The majority of cyanotic congenital cardiac defects are caused by the tetralogy of Fallot. Some symptoms include a biventricular connection of the aortic root, right ventricular hypertrophy, blockage of the right ventricular outflow tract, and a ventricular septal defect. Our understanding of tetralogy of Fallot (TOF) has significantly advanced since it was first described in 1888, and early diagnosis has led to improved surgical management and increased life expectancy. Adults with unrepaired and repaired TOF present with a range of late complications, including heart failure, the need for re-interventions, and late arrhythmias. Right ventricular (RV) failure, often caused by chronic pulmonary regurgitation, is a significant cause of heart failure in patients with TOF. Current treatment options are limited, and mainstay surgical procedures such as pulmonary-valve replacement (PVR), trans-annular repair (TAR), or infundibular widening repair have not shown a significant reduction in preventing right ventricular (RV) failure or death. Here, we explain the mechanisms of RV failure in ToF, chronic pulmonary regurgitation, heart failure, and secondary polycythemia. HF management in untreated adults is discussed. The progression of the disease, as well as complications, are also discussed. The treatment plan and the need to investigate the best management approach for this unsolved problem are included. This review aims to fill the knowledge gaps and supply valuable information regarding mechanisms of RV failure, chronic pulmonary regurgitation, and secondary polycythemia. To summarize, a new combat strategy must be found to battle RVF, and a more profound vision of these mechanisms is required. If it is not corrected, it will be one of the future research lines that will contribute to designing more efficacious treatment techniques for adults with TOF.

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Background and Aim: Patients with cyanosis secondary to congenital heart disease (CHD) are characterized by erythrocytosis and increased blood viscosity, which contribute to endothelial dysfunction, increased arterial stiffness, and impaired vascular function, which may affect the final clinical presentation. Asymmetric dimethylarginine (ADMA) and e-selectin (e-sel) are valuable biomarkers for endothelial and vascular dysfunction. Their concentration levels in blood serum have the potential to be an accessible tool that reflects the severity of the disease. We aimed to assess e-sel and ADMA levels and their relationship with the clinical status and endothelial and vascular function. Methods: A cross-sectional study, including 36 adult CHD cyanotic patients [(17 males) (42.3 ± 16.3 years)] with an arterial blood oxygen saturation less than 92% and 20 healthy controls [(10 males) (38.2 ± 8.5 years)], was performed. All the patients underwent a clinical examination, blood testing, and cardiopulmonary tests. Their endothelial function was assessed using the intima media thickness and flow-mediated dilatation. Vascular function, using applanation tonometry methods, was determined using the aortic systolic pressure, aortic pulse pressure, augmentation pressure, augmentation index, pulse pressure amplification, and pulse wave velocity. Results: The concentrations of e-sel and ADMA were significantly higher in the patients with CHD. The E-sel levels correlated positively with red blood cells, hemoglobin concentration, hematocrit, and augmentation pressure; they correlated negatively with blood oxygen saturation, the forced expiratory one-second volume, forced vital capacity, and oxygen uptake. The ADMA levels were found to correlate only with age. Conclusions: The E-sel level, unlike ADMA concentration, reflects the severity of erythrocytosis and hypoxia and, thus, the physical status of patients with cyanotic CHD.

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The pulmonary artery-to-left atrium (LA) fistula is one of the rare and unique structural causes of silent cyanosis. This correctable abnormality can be identified by having a high index of clinical suspicion and appropriate investigations using echocardiography and cardiac computed tomography (CT). We report an eight-year-old child who had worsening exertional dyspnea, long-standing central cyanosis, and recurrent infections. A large-sized fistula connecting the right pulmonary artery (RPA) to the LA with all the right- and left-sided pulmonary veins showed normal drainage into the LA, suggesting a type I RPA-to-LA fistula, which was diagnosed on cardiac CT. Percutaneous closure using the occluder device is planned as further management for the patient.

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Tetralogy of Fallot (TOF) is a common congenital heart disease (CHD) characterized by four distinct cardiac abnormalities. Brain abscess, though rare, is a life-threatening complication in patients with cyanotic congenital heart disease (CCHD), including TOF. This case report describes a 24-year-old female with unrepaired TOF who presented with symptoms of a brain abscess, including altered sensorium, fever, projectile vomiting, and headache. Diagnostic imaging with non-contrast-enhanced computed tomography (NCCT) revealed a well-defined hypodense lesion with a midline shift, prompting urgent drainage of the abscess. Subsequent cultures of the pus material identified Streptococcus intermedius as the causative agent, and the patient was maintained on antibiotics. This case highlights the importance of early diagnosis and surgical repair of TOF to prevent severe complications such as brain abscess, thereby reducing morbidity and mortality.

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Birth-associated structural issues with the heart are known as congenital heart disorders or defects. They might alter the heart's regular blood flow. A 10-month-old female child presented to a tertiary care hospital with symptoms of recurrent cyanotic spells with episodes of desaturation a few months after birth. ECG findings depicted a normal sinus rhythm with a right axis deviation along the right ventricular forces. Two-dimensional echocardiography showed a tetralogy of Fallot with pulmonary atresia with a patent ductus arteriosus from the undersurface of the arch with confluent small pulmonary arteries. A coronary wire was passed through the left subclavian artery, and a 4 × 16 mm stent was deployed successfully. After the procedure, the patient's saturation improved, and she was extubated on the table. The patient was on heparin for 24 hours and was started on oral aspirin thereafter. This case was discharged on the third postoperative day and was advised to follow up.

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Embryological misalignment between the aorta and pulmonary trunk gives rise to the congenital anomaly of the heart known as transposition of the great arteries (TGA). TGA is a type of parallel circulation, where the heart pumps oxygenated blood from the left ventricle into the pulmonary trunk. The deoxygenated blood from the right ventricle is circulated into the body as it pumps blood into the aorta. This type of parallel circulation is not compatible with life unless there is communication between oxygenated and deoxygenated blood. The presence of a ventricular septal defect (VSD) or patent ductus arteriosus (PDA) in TGA patients serves as this communication. Cyanosis in the first month of life is the most common presenting feature. We had a five-and-a-half-year-old male child presenting with cyanosis and congestive cardiac failure (CCF), along with infective endocarditis with mitral valve regurgitation, which is an unusual complication of dextro-TGA (d-TGA) with pulmonary stenosis (PS) with VSD.

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High-risk congenital heart disease (CHD) in pregnancy presents a complex clinical challenge. With improved medical care and increased survival rates, a growing population of adults with complex CHD are surviving to adulthood, including women of reproductive age. This chapter focuses on risk stratification and management of pregnant women with high-risk CHD, emphasizing the importance of considering both anatomical and physiological complexity. Maternal physiological changes, such as blood volume increase, cardiac output changes, and alterations in vascular resistance, can significantly impact high-risk CHD patients. Management of high-risk CHD in pregnancy necessitates a multidisciplinary approach and individualized care.

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BACKGROUND: Fetuses with cyanotic congenital heart disease (CHD) exhibit profound fetal circulatory disturbances that may affect early outcomes. OBJECTIVES: This study sought to investigate the relationship between fetal hemodynamics and early survival and neurodevelopmental (ND) outcomes in patients with cyanotic CHD. METHODS: In this longitudinal observational study, fetuses with cyanotic CHD underwent late gestational fetal cardiovascular magnetic resonance (CMR) to measure vessel blood flow and oxygen content. Superior vena cava (SVC) flow was used as a proxy for cerebral blood flow. Primary outcomes were 18-month mortality and Bayley Scales of Infant Development-III assessment. RESULTS: A total of 144 fetuses with cyanotic CHD were assessed. By 18 months, 18 patients (12.5%) died. Early mortality was associated with reduced combined ventricular output (P = 0.01), descending aortic flow (P = 0.04), and umbilical vein flow (P = 0.03). Of the surviving patients, 71 had ND outcomes assessed. Cerebral oxygen delivery was the fetal hemodynamic variable most strongly associated with cognitive, language, and motor outcomes (P < 0.05). Fetal SVC flow was also associated with cognitive, language, and motor outcomes (P < 0.01), and it remained an independent predictor of cognitive (P = 0.002) and language (P = 0.04) outcomes after adjusting for diagnosis. Diminished SVC flow also performed better than other fetal CMR and echocardiographic predictors of cognitive ND delay (receiver-operating characteristic curve area: 0.85; SE 0.05). CONCLUSIONS: Among fetuses with cyanotic CHD, diminished fetal combined ventricular output is associated with mortality, whereas cerebral blood flow and oxygen delivery are associated with early cognitive, language, and motor development at 18 months of age. These results support the inclusion of fetal CMR to help identify patients at risk of adverse ND outcomes.

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INTRODUCTION: Cyanotic nephropathy, a rare disease characterized by proteinuria, decreased estimated glomerular filtration rate, thrombocytopenia, polycythemia, and hyperuricemia, may occasionally be secondary to cyanotic congenital heart disease (CHD). There are currently no detailed diagnostic criteria or treatments for cyanotic nephropathy, owing to its extremely low incidence. Eisenmenger syndrome (ES) was initially defined by Paul Wood in pathophysiologic terms as "pulmonary hypertension (PH) at the systemic level, caused by a high pulmonary vascular resistance, with a reversed or bidirectional shunt at the aorto-pulmonary, ventricular, or atrial level." It typically develops in the presence of large, unrepaired atrial or ventricular septal defects, arterial shunts, or complex forms of CHD and is the most severe hemodynamic phenotype of pulmonary arterial hypertension associated with CHD. This study aimed to outline the case of an ES patient who developed cyanotic nephropathy and successfully achieved clinical remission through primary disease treatment and symptomatic management. Overall, this case expands our understanding of cyanotic nephropathy and lays a theoretical reference for the treatment of ES. CASE PRESENTATION: A 33-year-old Chinese female attended the outpatient department with abnormal urine test results over the past two and a half years. Following a comprehensive medical history collection, she underwent the necessary tests. Cardiac color ultrasound displayed a significant widening of the pulmonary artery and PH (severe), as well as mild tricuspid regurgitation and patent ductus arteriosus. The results of the kidney biopsy, combined with clinical findings, suggested a high risk of polycythemia-related kidney disease. She was eventually diagnosed with cyanotic nephropathy and ES. Her symptoms were relieved following symptomatic treatment, such as the administration of ambrisentan, febuxostat, and home oxygen therapy. Her follow-up visit at 6 months demonstrated improvements in hyperuricemia and a significant increase in physical strength. CONCLUSION: Cyanotic nephropathy is a rare condition in adults. Kidney biopsy remains the gold standard of diagnosis for various nephropathies. Active treatment of CHD and alleviating hypoxia may be pivotal for the treatment of cyanotic nephropathy.

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Tissue hypoxia increases erythropoietin production and release of immature erythrocytes that can be measured using nucleated red blood cell counts (nRBC). We hypothesized that hypoxia due to congenital heart disease (CHD) is chronic and is better tolerated than hypoxia due to respiratory disease (RD), which is an acute stress in newborns leading to higher nRBC. This study assesses the utility of nRBC as a marker to differentiate hypoxia due to CHD vs RD in term neonates. This was a single-center, retrospective study of term neonates with cyanosis from 2015 to 2022. Neonates < 37 weeks of gestation, with hypoxic-ischemic encephalopathy, and those with other causes of cyanosis were excluded. The patients were divided into 2 groups: cyanotic CHD and cyanotic RD. Clinical and laboratory data done within 12 h and 24-36 h after birth were collected. Data are represented as median and Interquartile range. Of 189 patients with cyanosis, 80 had CHD and 109 had RD. The absolute nRBC count at ≤ 12 h of age was lower in the CHD (360 cells/mm3) compared to RD group (2340 cells/mm3) despite the CHD group having significantly lower baseline saturations. A value of 1070 cells/mm3 was highly sensitive and specific for differentiating CHD from RD. The positive predictive value for this cut-off value of 1070 cells/mm3 was 0.94 and the negative predictive value was 0.89. The absolute nRBC is a simple screening test and is available worldwide. A nRBC < 1070 cells/mm3 in cyanotic newborns should hasten the search for CHD etiology with the possible need for prostaglandin therapy.

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Objective: We aimed to explore the feasibility of lung ultrasound for perioperative assessment and the optimal effect of lung ultrasound in reducing lung complications during non-cyanotic congenital heart disease (CHD) surgery using ultrafast-track anesthesia. Methods: Sixty patients were treated at Shenzhen Children's Hospital between 2019 and 2020. Of these, 30 patients in group N had an indication for extubation and ultrafast-track anesthesia after congenital heart surgery; the tracheal catheter was removed, and the patients were sent to the cardiac intensive care unit (CICU) for further monitoring and treatment. Another 30 patients were in group L and also had an indication for extubation and ultrafast-track anesthesia; in addition we compared lung ultrasound score (LUS) before and after surgery, when we found the cases that LUS ≥ 15, for whom targeted optimization treatment would be carried out. The tracheal catheter was removed after LUS <15 days before the patients were sent to the CICU. In all cases, the LUS and PaO2/FiO2 ratios (P/F) of both groups were recorded at the time of anesthesia induction (T0), before extubation (T1), and 5 min (T2), 1 h (T3), and 24 h (T4) after extubation. The incidence of pulmonary complications, LUS, and P/F were compared between the two groups. Results: There was great consistency between LUS and radiographic findings. Comparing the data of the two groups at T2, T3 and T4, the P/F was higher and the LUS was lower in group L than in group N. The incidence of lung complications in group L (18 cases, 60 %) was lower than that in group N (26 cases, 86.7 %, χ2 = 5.46, P = 0.02); comparing LUS between T0 and T3, LUS decreased in a greater number of cases in group L (15, 50 %) than in group N (7 cases, 23.3 %, χ2 = 4.59, P = 0.032). Conclusion: Lung ultrasonography can effectively help assess lung conditions. Optimization guided by lung ultrasound in ultrafast track anesthesia can significantly reduce postoperative lung complications.

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Brain abscesses are localized infections in the brain's parenchyma, characterized by inflammation, pus formation, and the development of a surrounding capsule. These lesions typically occur due to underlying factors such as immunosuppression, ear and sinus infections, and contamination during neurosurgery. While brain abscesses are a life-threatening complication of cyanotic heart defects, they are rarely reported, with only sporadic cases previously documented. This article presents the case of an eight-year-old male patient with an uncorrected transposition of the great arteries, who was evaluated for symptoms including headache, fever, and neurological focalization. Diagnostic imaging revealed three lesions consistent with brain abscesses. Furthermore, the causal agents were identified as Streptococcus intermedius and Fusobacterium spp., representing oral microorganisms. Additionally, the patient exhibited poor oral hygiene and dental caries in multiple teeth. This article discusses and integrates the possible pathophysiological mechanisms that allowed a localized dental infection to spread hematogenously and cause brain abscesses in this patient. Prompt management of the infectious source is crucial to prevent a poor prognosis associated with brain abscesses. Therefore, this case emphasizes the importance of regular dental assessments and thromboprophylaxis for patients with underlying cardiomyopathies that cause right-to-left shunting to prevent potential complications.

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Background and objective Complex congenital heart diseases (CHDs), such as the tetralogy of Fallot (TOF), often warrant reconstruction and augmentation of the right ventricular outflow tract (RVOT). This procedure requires the use of both synthetic and natural materials. However, finding the ideal material for tissue implants can be challenging. Biological materials often face issues such as tissue degeneration, calcium deposition, antigenicity, rejection, shrinkage, and fibrosis. These issues can lead to complications such as stenosis and insufficiency, potentially requiring early reoperations. In light of this, this study aimed to investigate the effectiveness of the Invengenx® bovine patch for RVOT reconstruction and augmentation. Methods This was a retrospective observational study conducted among eight children who underwent TOF correction cardiac surgery. Their demographic and clinical characteristics, intraoperative findings, and postoperative follow-up results at six months were collected from the hospital patient database. Results There were no deaths or complications in this study. We observed a significant reduction in the gradient across the pulmonary valve and the outflow tract at six months post-procedure. The analysis demonstrated that the Invengenx® bovine patch was successful and did not lead to any complications. Conclusions This study demonstrates the safety and efficacy of this engineered bovine pericardial patch (Invengenx®) as a cardiovascular substitute for surgical repair of both simple and more complex congenital cardiac defects.

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PURPOSE OF REVIEW: Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors that commonly produce excess catecholamines causing significant morbidity and mortality. Patients with cyanotic congenital heart disease (CCHD) develop PPGLs at a higher frequency than the general population. This review will summarize recent research in the association of PPGL and CCHD. RECENT FINDINGS: Advances in molecular genetics have provided new insights into a variety of germline mutations and somatic mutations related to PPGLs. In the CCHD population, mutations can occur in the hypoxia signaling pathway with gain-of-function somatic mutations in EPAS1, which prevent degradation of hypoxia-inducible factor-2 alpha. These mutations are implicated in oncogenesis. PPGLs associated with CCHD develop as early as age 15 years and have predominantly noradrenergic secretion. Surgical removal is considered the first line of therapy, although belzutifan, a HIF-2α inhibitor, is currently being tested as a potential therapy. Early screening with plasma metanephrines may assist in identifying PPGLs in patients with CCHD.

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A 58-year-old woman with tetralogy of Fallot was referred to our hospital with a 2-month history of hemoptysis and low-grade fever. The sputum smear on admission showed positive results for acid-fast bacilli, and comparative genomic analysis of the cultured sputum confirmed Mycobacteroides abscessus subsp. abscessus infection. Long-term combination antimicrobial therapy gradually improved the patient's symptoms. Although non-tuberculous mycobacteria infection is rarely observed in patients with cyanotic congenital heart disease, a worldwide increase in non-tuberculous mycobacteria infections may increase the incidence of this rare combination.

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INTRODUCTION AND IMPORTANCE: Brain abscess is an uncommon but potentially fatal infection of the brain parenchyma that can affect 5 % to 18.7 % of people with uncorrected complex congenital heart defects. In management of patients with complex cardiac defects, the main concern is that they are prone to develop perioperative complications. Hence such cases are a real challenge for surgeons and anesthesiologists. In this study we have reported a well-managed awake craniotomy (Awake-Asleep-Awake) for drainage of cerebral abscess in a patient with complex cardiac defect. CASE PRESENTATION: We present a case of a 13-year-old male patient with untreated cyanotic CHD-TOF with complete AV canal defect, who complained of right-side paralysis since 2 weeks; and has been suffering from headache, fever and vomiting for 25 days. Brain CT scan showed a large abscess in the left fronto-temporal lobes. Minimal access awake craniotomy with regional scalp nerve block and sedation was done and about 100-120 cc thick pus was drained. The patient's paralysis improved significantly and neurological deficit ceased on 3rd postoperative day. CLINICAL DISCUSSION: Pediatric population itself is a challenge for anesthesiologists and this manifolds when associated with complex cardiac defects and neurosurgery cases. CONCLUSION: Brain abscess is expected to be more common in patients following uncorrected complex congenital heart disease in developing countries. Physicians must hold a high index of suspicion for early diagnosis and well-management of these patients with multidisciplinary approach. Minimal access awake craniotomy with or without sedation for patients with large brain abscess is a safe surgical approach.

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BACKGROUND: Racial inequities in congenital heart disease (CHD) outcomes are well documented, but contributing factors warrant further investigation. We examined the interplay between race, socioeconomic position, and neonatal variables (prematurity and small for gestational age) on 1-year death in infants with CHD. We hypothesize that socioeconomic position mediates a significant part of observed racial disparities in CHD outcomes. METHODS: Linked birth/death files from the Natality database for all liveborn neonates in the United States were examined from 2014 to 2018. Infants with cyanotic CHD were identified. Non-Hispanic Black (NHB) and Hispanic infants were compared with non-Hispanic White (NHW) infants. The primary outcome was 1-year death. Socioeconomic position was defined as maternal education and insurance status. Variables included as mediators were prematurity, small for gestational age, and socioeconomic position. Structural equation modeling was used to calculate the contribution of each mediator to the disparity in 1-year death. RESULTS: We identified 7167 NHW, 1393 NHB, and 1920 Hispanic infants with cyanotic CHD. NHB race and Hispanic ethnicity were associated with increased 1-year death compared to NHW (OR, 1.43 [95% CI, 1.25-1.64] and 1.17 [95% CI, 1.03-1.33], respectively). The effect of socioeconomic position explained 28.2% (CI, 15.1-54.8) of the death disparity between NHB and NHW race and 100% (CI, 42.0-368) of the disparity between Hispanic and NHW. This was mainly driven by maternal education (21.3% [CI, 12.1-43.3] and 82.8% [CI, 33.1-317.8], respectively) while insurance status alone did not explain a significant percentage. The direct effect of race or ethnicity became nonsignificant: NHB versus NHW 43.1% (CI, -0.3 to 63.6) and Hispanic versus NHW -19.0% (CI, -329.4 to 45.3). CONCLUSIONS: Less privileged socioeconomic position, especially lower maternal education, explains a large portion of the 1-year death disparity in Black and Hispanic infants with CHD. These findings identify targets for social interventions to decrease racial disparities.

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Left pulmonary artery (LPA) stenosis with acute angulation commonly necessitates surgical revision in the treatment of tetralogy of Fallot (TOF). We investigated the clinical characteristics of acute angulation of the LPA in patients with TOF via computed tomography (CT). Between 2011 and 2022, 160 patients were diagnosed with TOF using CT. After excluding 28 patients due to insufficient records or age, 132 patients were included in the present analysis. The patients were divided into two groups according to the presence or absence of acute angulation of the LPA: group I (TOF with an acute angle of the LPA, n = 53) and group II (TOF without an acute angle of the LPA, n = 79). We retrospectively collected clinical data from electronic medical records. T-tests were used to analyze continuous variables (i.e., age, sex, weight, right ventricular outflow tract [RVOT] pressure on echocardiography, and distance to bifurcation), and Fisher's exact and chi-square tests were used to analyze categorical data (i.e., presence of the right aortic arch, pulmonary arterial atresia/hypoplasia, atrial septal defect [ASD], patent ductus arteriosus [PDA], and pulmonary valve). The groups did not differ significantly in terms of sex, weight, presence of the right aortic arch, pulmonary arterial atresia/hypoplasia, ASD, or distance to the bifurcation. Moreover, there was no significant difference between the presence and absence of PDA (P = 0.057); however, patients in group I were significantly older (143.2 ± 97.8 days) than those in group II (91.1 ± 76.0 days, P = 0.002). Furthermore, RVOT pressure was significantly higher among patients in group I (45.1 ± 22.5 mmHg) than in group II (25.0 ± 12.4 mmHg, P < 0.001). In the current study, acute angulation of the LPA in patients with TOF, as observed on CT, was associated with older age and higher RVOT pressure on echocardiography.

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Background: Congenital ductal-dependent cyanotic congenital heart disease (CHD) is a group of diseases that require early intervention during early infancy or the neonatal period. In this study, we compared the effectiveness, safety, and side effects of stenting patent ductus arteriosus versus a modified Blalock-Taussig (BT) shunt. Materials and Methods: Thirty-six neonates and infants with cyanotic CHD who were <6 months old and were not suitable for complete surgery were admitted to Chamran Hospital in Isfahan and enrolled in this prospective longitudinal cross-sectional study. Ductal stenting (DS) was performed in 18 patients and BT shunt in 18 patients. Data were collected and compared in these patients. Results: Age, height, and weight were lower in the DS group compared to the shunt group (1.28 ± 0.46 vs. 2.50 ± 0.51 months, 53.22 ± 1.80 vs. 56.11 ± 1.67 cm, 3.38 ± 0.45 vs. 4.98 ± 0.57 kg, respectively P < 0.001). The duration of the intensive care unit stay as well as hospital stay in patients in the DS group was much shorter than the shunt group (1.33 ± 0.68 vs. 2.83 ± 0.70 days, 3.33 ± 0.68 vs. 9.55 ± 0.51, P < 0.001, respectively). In both groups, the diameter of the pulmonary branches increased after the procedure compared to before the procedure (P < 0.001). Furthermore, the patient's hemoglobin was significantly decreased compared to before the procedure (P < 0.001). In both groups, one patient died in the postprocedure period. In ductal stent group one patient died in catheterization lab and in shunt group died 48 hours after surgery. There was no significant difference in postprocedural complications between the two groups. Conclusion: Duct stents can be used as an effective and safe method in duct-dependent cyanotic CHD patients who are not suitable candidates for complete surgery. As operators become proficient, this method can be a good alternative to BT shunts with fewer complications.