UNASSIGNED: Methemoglobin is an altered state of hemoglobin where iron in hemoglobin is oxidized and incapable of binding oxygen; leading to complications such as cyanosis, dyspnea, headache, and heart failure. Methemoglobinemia can be congenital or acquired. Congenital methemoglobinemia is a rare disease and its worldwide incidence is unclear. We recently encountered the first documented case of congenital methemoglobinemia at our institution, necessitating perioperative care.
UNASSIGNED: In the present case, a 22-year-old man with congenital methemoglobinemia underwent general anesthesia for dental extraction. The surgeon was informed to avoid local anesthetics and oxygenation was performed with FiO2 of 1.0. Arterial blood gas analysis showed a PH of 7.337, PaO2 of 302 mm Hg, PaCO2 of 44 mm Hg, oxyhemoglobin level of 63.4%, and methemoglobin level of 37.8%. The patient had a stable course. No methylene blue therapy was required, although cyanosis was observed during surgery.
UNASSIGNED: In summary, though rare, congenital methemoglobinemia poses fatal risks during surgery. Its management involves preoperative recognition and optimization, oxygenation status, multidisciplinary care, avoiding precipitating or oxidizing agents, discussing treatment options, maintaining cardiopulmonary stability, and ensuring perioperative safety measures with the medical team.

BACKGROUND: In light of prolonged hypoxia, children with cyanotic heart disase (CHD) are at a high risk of developing iron deficiency iron deficiency (ID) and iron deficiency anemia (IDA). Reticulocyte hemoglobin equivalent (Ret-He) is a novel and dependable indicator for assessing iron status. However, there has been no previous study regarding cut-off value in pediatric CHD group. The purpose of this study is to assess the role of Ret-He and to establish cut-off points in the diagnosis of iron deficiency and IDA in pediatric cyanotic heart disease.
METHODS: This study was conducted in two tertiary hospitals in Jakarta, Indonesia. 59 children with CHD, aged 3 months to 18 years, were enrolled consecutively. To determine iron status, hematological parameters (hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin) and biochemical parameters for iron status (serum ferritin, transferrin saturation) were analysed and compared to Ret-He levels. The receiver operating characteristic (ROC) analysis was performed for the Ret-He cut-off points for ID and IDA. Sensitivity, specificity, positive and negative predictive value were calculated for each cut-off point.
RESULTS: Normal iron status was identified in 27 (45.8%) subjects, ID in 8 (13.5%) subjects, and IDA 24 (40.7%) subjects. The ID cut-off value for Ret-He is 28.8 pg (sensitivity 75%, specificity 85.2%, PPV 60%, NPV 92%, and AUC 0.828) and the Ret-He cut-off point for IDA is 28.15 pg (sensitivity 75%, specificity 88.9%, PPV 85.7%, NPV 80%, and AUC 0.824). Hemoglobin should be used in conjunction with Ret-He. ID might be detected in this cohort with Ret-He 28.8 pg and hemoglobin > 16,5 g/dL. While Ret-He 28.15 pg or Ret-He 28.15-28.8 pg with hemoglobin 16.5 g/dL could be used to diagnose IDA.
CONCLUSIONS: The reticulocyte hemolgobin equivalent could be utilised as an iron status parameter in pediatric CHD, with a cut-off value of 28.8 pg for ID and 28.15 pg for IDA.

BACKGROUND: There is a high mortality rate in cyanotic patients with congenital heart disease (CHD) due to cardiovascular complications. The cardiovascular prognosis is negatively affected by endothelium dysfunction, increased arterial stiffness, and impaired vascular system. This study aimed to determine carotid intimal mean thickness (CIMT) and flow-mediated dilatation (FMD) in a group of children with cyanotic CHD (CCHD).
METHODS: FMD and CIMT were evaluated for 45 children with CHKD and 38 patients who did not have CHKD over the period 2021 to 2022, as part of this case-control study. In terms of age and gender, the case group has been compared to controls.
RESULTS: Men accounted for 61.3% of the participants, with a mean standard deviation age of 7.8 5.39 years. In subjects with CCHD, CIMT increased non-significantly and FMD decreased significantly, but systolic blood pressure was significantly higher in patients than in the healthy group. (P=0.003).
CONCLUSIONS: FMD was reduced in children with CCHD, but in controls, systolic blood pressure and CIMT were lower. The risk of developing atherosclerosis in CCHD patients may be increased by an increase in CIMT and systolic blood pressure.

UNASSIGNED: Complete repair (CR) can be delayed in neonates with symptomatic tetralogy of Fallot (sTOF) using surgical or transcatheter palliation to relieve cyanosis. Balloon pulmonary valvuloplasty (BPV) is an established treatment for pulmonary valve stenosis; however, its effectiveness in palliating neonates with sTOF has not been well investigated.
UNASSIGNED: A retrospective chart review between 2005 and 2017 on neonates with sTOF who underwent initial BPV from 9 participating centers of the Congenital Cardiac Research Collaborative was performed. Primary outcome was CR at >30 days after BPV without interval reintervention (RI).
UNASSIGNED: In total, 47 neonates with sTOF underwent BPV, of whom 27 (57%) underwent CR at >30 days after BPV without RI. The median time to CR was 151 days (106-210). RI before CR occurred in 17 patients (36%): surgical shunt (n = 7), outflow tract stenting (n = 6), patent ductus arteriosus stenting (n = 2), and surgical outflow patch (n = 2). Valve-sparing repair at CR was performed in 6 patients (13%) after initial BPV. RI or CR ≤30 days from BPV was associated with smaller infundibular diastolic diameter (P = .004). An infundibular diastolic diameter of <3.4 mm demonstrated 75% sensitivity and 67% specificity to predict early CR or RI.
UNASSIGNED: BPV can be an effective palliative therapy in select neonates with sTOF to delay CR. A smaller diastolic infundibulum diameter is a predictor of RI or early CR, and valve-sparing repair is uncommon, making patient selection and alternative palliative methods key when considering BPV palliation in neonates with sTOF.

BACKGROUND: Absent Pulmonary Valve Syndrome (APVS) is a rare birth defect where the pulmonary valve is missing or underdeveloped. APVS often occurs alongside Tetralogy of Fallot, (TOF) another heart defect.
METHODS: A 33-year-old woman gave birth to a male infant with severe pulmonary stenosis (PS) and a large ventricular septal defect (VSD). The infant underwent surgery to close the VSD and resect the stenotic ring. Two years later, he remained asymptomatic with a closed VSD and no pulmonary valve gradient.
CONCLUSIONS: Despite high mortality rates, long-term survival has improved with advancements in surgical repair. This case underscores the significance of early detection and personalized surgical strategies for complex congenital heart defects.
CONCLUSIONS: Early identification of subtle symptoms is crucial for timely intervention, while individualized surgical strategies optimize outcomes. Further research is needed to understand the complex interplay of cardiac anomalies in APVS, particularly the absence of a patent ductus arteriosus in this case.

Methemoglobinemia is a rare dyshemoglobin disorder which can either be congenital or acquired. Dyshemoglobin disorders can be asymptomatic or symptomatic. We narrate the case of a 12-year-old girl who presented with a fever, cough, and oxygen saturation of 85%. She was diagnosed with COVID-19, along with a large atrial septal defect and pulmonary arterial hypertension. Arterial blood gas analysis revealed normal partial pressure of oxygen and on 100% exposure to oxygen, blood color turned chocolate brown. After the resolution of COVID-19 in 10 days, the patient was treated with oral ascorbic acid and successful atrial septal defect repair. It is important to suspect dyshemoglobin disorder in a patient who presents with hypoxia/hypoxemia.

Abernethy syndrome is a rare congenital malformation stemming from a portosystemic shunt. Diagnosis proves challenging due to nonspecific clinical symptoms, with presentation varying based on age and disease severity. Consequences include hepatic, cardiovascular, renal, gastrointestinal, and neurological complications, and growth retardation. We report the case of a child presenting with perioral and digital cyanosis, observed in early childhood. Clinical examination revealed low saturation, telangiectasias, digital clubbing, and collateral venous circulation in the thorax. Imaging confirmed the diagnosis of Abernethy syndrome.

Total anomalous pulmonary venous return (TAPVR) represents a group of anomalies consisting of a lack of connection between the pulmonary veins and the left atrium. All oxygenated pulmonary venous return flows directly or indirectly into the right atrium. Survival is only possible with a right-to-left atrial shunt. It remains rare, accounting for less than 1% of all congenital heart diseases. Its association with tetralogy of Fallot is much rarer and has been documented in medical literature as isolated cases. Early prenatal diagnosis, rapid surgical repair, and optimal postoperative resuscitation appear to be the best guarantee of a favorable outcome following total repair of a pulmonary venous connection anomaly. Non-obstructed forms present as high-flow shunts with moderate cyanosis. The symptomatology of blocked forms is dominated by the obstruction to venous return; a clinical picture of respiratory distress with intense cyanosis and severe pulmonary arterial hypertension develops from the first days of life. Echocardiography is fundamental in diagnosing TAPVR. If the results are inconclusive, magnetic resonance imaging and computed tomography are appropriate alternatives for establishing a complete and accurate diagnosis. We report a case of a two-month and 22-day-old infant who is a product of a twin pregnancy, presenting with a non-obstructed TAPVR associated with tetralogy of Fallot, and his twin who died on day 20 of life, likely due to a complex cyanotic congenital heart disease.

Methemoglobinemia secondary to administration of hydroxyurea is only reported in veterinary medicine as a result of accidental ingestion of high doses, and once at therapeutic dose in human medicine. A 2.5-year-old female spayed mixed breed dog was presented for acute signs of neurologic disease and diagnosed with severe erythrocytosis without an identified underlying cause, leading to suspicion of polycythemia vera. The dog was managed with phlebotomies, supportive care, and administration of hydroxyurea. Within 2 h of administration of hydroxyurea (37 mg/kg) administration, respiratory distress with cyanosis, and methemoglobinemia developed. Signs resolved within 24 h but recurred after a second administration of lower dosage of hydroxyurea (17 mg/kg) 20 days later. The dog remained asymptomatic except for mild cyanosis but was humanely euthanized for lack of relevant improvement of signs of neurologic disease. This case report documents the repeated occurrence of methemoglobinemia in a dog after administration of hydroxyurea at therapeutic doses.

Indoxacarb, an oxadiazine insecticide, is known for its selective lethality by blocking neuronal voltage-dependent sodium channels. While primarily developed to target insect populations resistant to other pesticides, its toxicity in humans remains poorly understood. We present a case of methemoglobinemia resulting from indoxacarb ingestion, a rare manifestation of its toxic effects. A 38-year-old farmer attempted suicide by ingesting the insecticide, leading to cyanosis, hypoxemia, and characteristic arterial blood gas findings indicative of methemoglobinemia. Prompt diagnosis was challenging due to the absence of specific tests, necessitating clinical suspicion. Treatment with methylene blue and supportive therapy resulted in significant clinical improvement, highlighting the importance of early intervention in managing indoxacarb poisoning. This case underscores the need for increased awareness among healthcare providers regarding the potential toxic effects of indoxacarb. It emphasizes the importance of prompt recognition and treatment of methemoglobinemia in pesticide-related poisonings. Further research is warranted to elucidate the mechanisms underlying indoxacarb toxicity in humans and to optimize treatment strategies for affected individuals.