An Extremely Preterm Infant Born at 23 Weeks' Gestation With an Interrupted Aortic Arch Complex: A Case Report.

We present a case of an infant male born at 23 weeks' gestation with an interrupted aortic arch (IAA) complex. We treated the patient with hypoxic gas ventilation to address developing systemic undercirculation in the acute postnatal phase. As the symptoms of bronchopulmonary dysplasia evolved, hypoxic gas ventilation was no longer required to stabilize the hemodynamics. The patient was discharged home after undergoing the palliative surgical procedure of bilateral pulmonary artery banding and ductus arteriosus stent implantation. Although he suffered from pulmonary hypertension, it was controllable with oxygen supplementation and pulmonary vasodilators. There are limited therapeutic options available for extremely preterm infants with critical congenital heart defects (CHDs). Hypoxic gas ventilation might be considered as one of the options, with its risks taken into account, to manage extremely preterm infants with CHDs with pulmonary overcirculation before performing surgical interventions.

Transient Recovery of Complete Atrioventricular Block Due to Maternal Anti-SS-A Antibody Through Antenatal Steroid Administration After 27 Weeks of Gestation.

Maternal anti-SS-A antibodies may cause complete atrioventricular block or myocardial damage in a fetus. Effective treatment for this has not been established. Although antenatal steroids may be a treatment option for anti-SS-A antibody-related myocarditis or atrioventricular block, a complete atrioventricular block is usually considered irreversible once established. Previous reports have indicated that, in cases where antenatal steroids were effective for atrioventricular block, they were administered earlier in the pregnancy. Here we present a case where maternal steroid administration initiated from 27 weeks, which is beyond the recommended optimal treatment period, was effective in altering a complete atrioventricular block to a grade I atrioventricular block.

Induction of aggressive arterial and venous dilation therapy in addition to pulmonary dilation therapy (super-Fontan strategy) improves Fontan circulation both at rest and during treadmill exercise.

Objective: Fontan circulation maintains preload and cardiac output by reducing venous capacitance and increasing central venous pressure (CVP). The resultant congestive end-organ damage affects patient prognosis. Therefore, a better circulatory management strategy to ameliorate organ congestion is required in patients with Fontan circulation. We sought to verify whether aggressive arterial and venous dilation therapy in addition to pulmonary dilation (super-Fontan strategy) can improve Fontan circulation and reduce congestion. Methods: Patients after Fontan surgery who received the super-Fontan strategy in a single center were recruited. Participants were examined using medical records between 2010 and 2018. We retrospectively analyzed the changes in hemodynamics at rest and during treadmill exercise before and after the introduction of this therapy. Results: The therapy significantly increased venous capacitance (3.21 ± 1.27 mL/kg/mm Hg to 3.79 ± 1.30 mL/kg/mm Hg, P = .017) and decreased total pulmonary resistance, leading to significantly reduced CVP (11.7 ± 2.4 mm Hg to 9.7 ± 2.2 mm Hg, P < .001) and increased cardiac index (CI) (3.09 ± 1.01 L/min/m2 to 3.54 ± 1.19 L/min/m2, P = .047). Furthermore, this strategy significantly reduced the elevations in CVP (19.6 ± 5.3 mm Hg to 15.4 ± 2.7 mm Hg, P = .002) with preserved CI in response to exercise. CVP at rest and during exercise was significantly positively correlated with serum markers of hepatic congestion and fibrosis, respectively. Conclusions: The super-Fontan strategy is a therapy that turns the heart failure condition of Fontan circulation into a more physiological condition. However, whether the strategy improves long-term prognosis warrants further studies.

Successful Pacemaker Setting Using Treadmill Exercise Test in a Child with Fontan Circulation.

The usefulness of a treadmill exercise test for determining optimal pacemaker settings remains unknown. An 8-year-old boy with Fontan circulation and a dual-chamber pacemaker for a rate-dependent advanced atrioventricular block suffered from dullness and poor school attendance. Although the pacemaker log showed an atrial tachycardia/fibrillation episode, treadmill exercise testing revealed sinus tachycardia, which converted to a 2:1 atrioventricular block. The pacemaker setting was optimized, with improvement in the patient's condition.Treadmill exercise testing helps optimize dual-chamber pacemaker settings in children with complex congenital heart disease involved in energy-consuming physical activities and having a wide working range in sinus rate.

First Pediatric Case of Clinically-Diagnosed Penicillin G-Induced Hemorrhagic Cystitis.

Hemorrhagic cystitis is a diffuse inflammatory disease of the urinary bladder associated with macrohematuria. Several cases of hemorrhagic cystitis caused by penicillin G have been reported in adults but not children. Here we describe the first pediatric case of clinically-diagnosed penicillin G-induced hemorrhagic cystitis. The patient was a 9-year-old boy with a ventricular septal defect, chromosomal abnormalities, and infective endocarditis caused by Abiotrophia defectiva. After approximately four weeks of penicillin G administration, he had a culture-negative major hemorrhage with a clot. The hematuria resolved one week after penicillin G discontinuation, and a drug lymphocyte stimulation test for penicillin G was positive. In conclusion, penicillin G can also induce hemorrhagic cystitis in children. When large doses of penicillin G are used for long periods in adults or children, the patient should be monitored for hemorrhagic cystitis.

Efficacy of a Subcutaneous Implantable Cardioverter Defibrillator in a Child with Early Repolarization Syndrome.

An early repolarization (ER) pattern or J waves are considered to be a benign finding observed in the healthy population, however, it has been pointed out that the ER pattern seen in the inferolateral leads could be an independent risk factor for fatal arrhythmias. We present a pediatric case in which early repolarization syndrome (ERS) was suspected due to the presence of ER or J waves in the inferior leads, which eventually disappeared after the administration of pilsicainide. During the follow-up period, several fatal ventricular arrhythmias were recorded after implantation of a subcutaneous implantable cardiac defibrillator (S-ICD). This report describes the efficacy of S-ICDs in a child with an ER pattern after aborted sudden cardiac death.

Child with Kawasaki Disease Complicated by A Single Right Coronary Artery.

A 3-year-old boy was referred to our hospital for management of Kawasaki disease at 5 days of illness. Echocardiographic examination on admission suggested aneurysmal dilation of the right coronary artery and a possible aorta-left main trunk connection. However, detailed echocardiography at 12 days of illness revealed an abnormal bifurcation of the proximal right coronary artery and no real connection of the aorta-left main trunk, all of which indicated the presence of a single right coronary artery. These diagnoses were confirmed by selective coronary angiography, which was performed later. Considering the difficulties in diagnosing congenital coronary anomalies, which may increase the risk of future fatal events, knowing the disease entity of the congenital coronary arterial anomaly is important for the accurate evaluation of coronary arteries in patients with Kawasaki disease. To the best of our knowledge, this is the first case report of a patient with Kawasaki disease complicated by a single right coronary artery; however, following a search of the literature, we found a brief conference abstract written in Japanese relating to the same clinical condition.

Markedly long pause due to sinus arrest during dexmedetomidine use and nasal continuous positive airway pressure in two infants with respiratory syncytial virus infection.

Nasal respiratory support for infants with respiratory distress caused by respiratory syncytial (RS) virus infection sometimes requires appropriate sedation. Dexmedetomidine can be an alternative sedative because of its advantage of less frequent respiratory suppression. We report the cases of twin infants with RS virus infection who showed unreported long pauses (4 and 10 s) due to sinus arrest while receiving dexmedetomidine. After termination of dexmedetomidine administration, the long pause of >2 s was no longer observed in both cases. RS virus infection may inhibit the conduction system and sometimes induce bradyarrhythmia. Cardiac and sinus arrests are reported as complications of dexmedetomidine administration. Thus, because dexmedetomidine administration and RS virus infection may additively or synergistically inhibit the conduction system, the use of dexmedetomidine in infantile RS infection should be carefully considered. If sedation is unavoidable, other drugs should be used first. An evidence-based safe regimen for sedation in infants with RS infection should be established in the near future. .

Progression of left ventricular apical hypoplasia-like restrictive cardiomyopathy with severe pulmonary hypertension: Follow-up from fetal stage.

Left ventricular (LV) apical hypoplasia is a rare restrictive cardiomyopathy subtype with an unclear pathophysiology. LV apical hypoplasia typically presents with elongated right ventricle (RV) wrapping around a truncated and spherical LV with a deficient apex (the "banana-shape" of the RV). Here we report a case of a young boy with apparent LV apical hypoplasia that developed after birth; no "banana-shaped" RV was observed during the fetal period. Moreover, suprasystemic pulmonary hypertension (PH) developed even after a mitral valve replacement was performed for progressive mitral stenosis and regurgitation at 14 months of age. He underwent surgery for the Potts shunt, a shunt between the pulmonary artery and aorta, at 13 years to secure systemic output. His PH ameliorated and his heart failure remained stable for 3 years after the operation. This case indicates that the "banana-shaped" RV seen in this condition is not always congenital but that it can form and develop after birth. Furthermore, this case supports the usefulness of the Potts shunt as a therapeutic option in patients with severe PH due to LV apical hypoplasia. .

Steroid-Refractory Protein-Losing Enteropathy with Gastrointestinal Bleeding in a Patient with Fontan Circulation.

Protein-losing enteropathy (PLE) is one of the major complications after a Fontan operation. Some PLE patients suffer from concurrent gastrointestinal bleeding. An effective treatment regimen for such patients has not been established yet. Further, it remains unknown whether PLE and gastrointestinal bleeding coexist independently, or protein losing is associated with gastrointestinal bleeding. We report a 7-year-old steroid-refractory post-Fontan PLE case suggesting the latter pathogenesis together with a literature review.

Prevalence of Short Stature and Growth Hormone Deficiency and Factors Associated With Short Stature After Fontan Surgery.

Background: Fontan circulation is characterized by many features commonly observed in heart failure that may affect physical growth regardless of pituitary gland dysfunction status. The aims of the present study were to investigate the prevalence of short stature and growth hormone deficiency (GHD) and determine the factors associated with short stature after Fontan surgery. Methods and Results: On retrospective evaluation of 47 patients after Fontan surgery, a very high prevalence of short stature was observed (38.3%). In the short stature group, 5 patients were diagnosed with GHD (10.6% of patients after Fontan Surgery), which is much higher than the frequency of 1/10,000 in the general population. Central venous pressure (CVP) was significantly higher (14.6±4.5 vs. 12.2±1.9 mmHg, P<0.05) and the blood pressure and arterial oxygen saturation were significantly lower in the short stature group. Laboratory data also indicated volume retention and congestion in the short stature group. Mean change in stature from catheterization 1 year after Fontan surgery to the most recent visit was significantly lower in the short stature group (-1.1±1.1 SD vs. 0.0±0.8 SD, P<0.05) and significantly negatively correlated with CVP (r=-0.42, P<0.05). Conclusions: Volume retention and congestion, the prominent features of Fontan circulation, affect physical growth partly due to pituitary gland dysfunction, highlighting the need for the screening for and treatment of this condition after Fontan surgery.

Postnatal Amelioration of Fetal Right Ventricular Hypoplasia Associated with Large Eustachian Valve: A Case Report.

In fetuses, the Eustachian valve directs oxygenated blood returning from the inferior vena cava into the left atrium via the foramen ovale. If too large, the Eustachian valve can restrict right ventricular inflow, as well as induce postnatal cyanosis via an interatrial right-to-left shunt. We report a fetal case of postnatal amelioration of the tricuspid valve and right ventricle hypoplasia, despite significant right ventricular hypoplasia associated with a large Eustachian valve. Application of an appropriate respiratory management regimen to help reduce pulmonary vascular resistance is of particular importance for the reversal of the right-to-left shunt via the foramen ovale and associated increases in right ventricular inflow.

Modified underlying cardiac disease severity in twin-twin transfusion syndrome.

Twin-twin transfusion syndrome or related conditions affect fetal loading. We report monochorionic-diamniotic twins. Twin 1 had Ebstein anomaly with mild tricuspid regurgitation (TR) and slightly thickened tricuspid valve leaflets with plastering. Twin 2 had tricuspid valve dysplasia (with abnormal thickening but without plastering) with moderate TR and mild right atrial dilatation. After birth, the severity of TR was greatly reduced in the recipient but increased in the donor. Therefore, intravascular volume change which was due to twin-twin transfusion syndrome seemed to affect the severity of the valvar disease in fetuses. This case suggests that the intrinsic severity of fetal tricuspid valvular disease may be overestimated in the recipient and underestimated in the donor twin. These factors need to be taken into consideration in clinical decision-making.

Two Extremely Low Birth Weight Infants Who Survived Functional Pulmonary Atresia with Normal Intracardiac Anatomy.

For the first time, we report about two extremely low birth weight infants who were born at 25 and 22 weeks' gestation and who survived functional pulmonary atresia (fPA) with normal intracardiac anatomy. A slow, reflected, and bimodal blood flow pattern in the pulmonary artery (both cases) and the presence of pulmonary regurgitation (1 case) were useful for diagnosing fPA. Timely use of lipo-prostaglandin E1 to maintain adequate pulmonary flow and reduce pulmonary arterial resistance and sodium bicarbonate to improve acidosis were effective treatments to attain forward flow. As optimal management is essential for the intact survival of extremely early preterm infants and the accurate diagnosis of fPA is difficult without the awareness of the disease entity, our cases underline the importance of recognizing that fPA can occur even in extremely low birth weight infants with normal intracardiac anatomy.

Improvement in Dyssynchrony with Pharmacological Ablation of Right-Sided Accessory Pathway-Induced Cardiomyopathy in Infants.

Right-sided accessary pathways in patients with Wolff-Parkinson-White (WPW) syndrome may cause cardiac dyssynchrony and dilated cardiomyopathy, with a characteristic septal shape, irrespective of any supraventricular tachycardia episodes. We report on two infants (13 and 5 months), whose right-sided accessary pathway-induced dilated cardiomyopathy was successfully treated by flecainide for the first time. After the flecainide administration, an abnormal aneurysmal dilation of the basal interventricular septum was almost restored to normal, and the decreased ejection fraction recovered. Flecainide use may be an important therapeutic option for this entity to avoid catheter ablation during infancy.

First Report of Fatal Secondary Abdominal Compartment Syndrome Induced by Intestinal Gas Accumulation without Organic Occlusive Intestinal Lesion in a Child with Sepsis.

BACKGROUND Abdominal compartment syndrome (ACS), characterized by an increased intra-abdominal pressure and new-onset organ dysfunction, is a critical and potentially fatal condition, with no case of ACS caused by intestinal gas without intestinal lesion being reported to date. CASE REPORT A 2-year-old girl with a chromosomal abnormality of 1p36 deletion presented with fever and diarrhea following upper-gastrointestinal series for the evaluation of gastroesophageal reflux. After 20 days, she experienced septic shock and multiple-organ failure, accompanied with rapidly growing, severe abdominal distension. A marked increase in the intra-abdominal pressure was indicated by the complete loss of elasticity in the extremely hard and distended abdomen. She died 14 h after the onset of shock. Her autopsy examination revealed extensive pneumonia and excessive intestinal gas, despite no occlusive intestinal lesion present. CONCLUSIONS It is critical to be aware that secondary ACS can occur following sepsis due to the accumulation of extensive intestinal gas, without an occlusive intestinal lesion.

Blood reservoir function in patients with Fontan circulation and asplenia syndrome.

Splanchnic circulation constitutes a major portion of the vasculature capacitance and plays an important role in maintaining blood perfusion. Because patients with asplenia syndrome lack this vascular bed as a blood reservoir, they may have a unique blood volume and distribution, which may be related to their vulnerability to the haemodynamic changes often observed in clinical practice. During cardiac catheterisation, the mean circulatory filling pressure was calculated with the Valsalva manoeuvre in 19 patients with Fontan circulation, including 5 patients with asplenia syndrome. We also measured the cardiac output index and circulatory blood volume by using a dye dilution technique. The blood volume and the mean circulatory filling pressure and the venous capacitance in patients with asplenia syndrome were similar to those in the remaining patients with Fontan circulation (85 ± 14 versus 77 ± 18 ml/kg, p = 0.43, 31 ± 8 versus 27 ± 5 mmHg, p = 0.19, 2.8 ± 0.6 versus 2.9 ± 0.9 ml/kg/mmHg, p = 0.86). Unexpectedly, our data indicated that patients with asplenia syndrome, who lack splanchnic capacitance circulation, have blood volume and venous capacitance comparable to those in patients with splanchnic circulation. These data suggest that (1) there is a blood reservoir other than the spleen even in patients with asplenia; (2) considering the large blood pool of the spleen, the presence of a symmetrical liver may represent the possible organ functioning as a blood reservoir in asplenia syndrome; and (3) if this is indeed the case, there may be a higher risk of hepatic congestion in patients with Fontan circulation with asplenia syndrome than in those without.

Case of Incomplete Kawasaki Disease with No Symptoms Except Fever Causing the Development of Coronary Aneurysm.

Incomplete Kawasaki disease (iKD), which does not satisfy the standard KD diagnostic criteria because the required number of principal symptoms is not met, sometimes causes coronary aneurysms. Here we report the case of a patient with iKD who presented with only one principal symptom that resulted in the development of coronary aneurysm, as evidenced by angiography.