The CXCL10-CXCR3 axis plays an important role in Kawasaki disease.

The precise pathogenesis of Kawasaki disease remains unknown. In an attempt to elucidate the pathogenesis of KD through the analysis of acquired immunity, we comprehensively examined the immunophenotypic changes in immune cells such as lymphocytes and monocytes along with various cytokines, focusing on differences between pre- and post- treatment samples. We found high levels of CXCL9 and CXCL10 chemokines that decreased with treatment, which coincided with a post-treatment expansion of Th1 cells expressing CXCR3. Our results show that the CXCL10-CXCR3 axis plays an important role in the pathogenesis of KD.

A novel case of congenital hepatic arterio-veno-portal shunts with umbilical vein aneurysm.

A term male infant presented with congenital hepatic arterio-veno-portal shunts. A mass-like lesion in the left lobe of the liver received blood supply from not only the umbilical vein, but also the hepatic and inferior intrahepatic arteries, communicating with the hepatic and portal veins in a complicated manner, with an umbilical vein aneurysm. The blood flow of the arterio-veno-portal shunts spontaneously and gradually declined from the neonatal period to six years of age. Although mild high-output cardiac failure had developed, no life-threatening events or health problems originating from portosystemic shunts, such as pulmonary artery hypertension and hepatopulmonary syndrome, were observed. However, this report shows that scrupulous follow-up to identify pulmonary artery hypertension and hepatopulmonary syndrome should be continued because complete resolution of the arterio-veno-portal shunts was not obtained in this case.

Abdominal aortic thrombus formation in a neonate with an interrupted aortic arch.

We note the risk of paradoxical embolism in patients with congenital heart defects with a right-to-left shunt. These patients should be managed to ensure that abdominal aortic thrombi are not overlooked when their clinical conditions change.

Mexiletine infusion challenge test for neonatal long QT syndrome with 2:1 atrioventricular block.

For applying a genotype-based treatment in neonatal long QT syndrome (LQTS), early detection of the genotype becomes an important issue. We report a case of a neonate with LQTS type 3 that presented with 2:1 atrioventricular block and underwent a mexiletine infusion challenge test, and achieved shortening of the QTc and 1:1 atrioventricular conduction. The mexiletine infusion challenge test was helpful to make an early detection of the genotype of the LQTS and predicted the drug efficacy in a neonatal patient.

Prenatal Diagnosis of Atrioventricular Block and QT Interval Prolongation by Fetal Magnetocardiography in a Fetus with Trisomy 18 and SCN5A R1193Q Variant.

We report a case of fetal trisomy 18 with SCN5A R1193Q variant that presented with sinus bradycardia, 2 : 1 atrioventricular block (AVB), and QT interval prolongation. These complex arrhythmias were diagnosed by fetal magnetocardiography combined with ultrasound findings. Advanced AVB and ventricular arrhythmias were confirmed after birth. Genetic testing of the baby revealed a SCN5A R1193Q variant, which we considered could account for the various arrhythmias in this case.

Nontraditional placement of an implantable cardioverter-defibrillator in a heterotaxy patient after the completion of total cavopulmonary connection.

A 15-year-old boy with heterotaxy syndrome developed a prolonged QT interval and intractable torsade de pointes after the administration of sodium channel blockers for atrial tachyarrhythmia. Although this situation called for the placement of an implantable cardioverter-defibrillator, a conventional transvenous approach was not available since the patient had previously undergone a nonfenestrated extracardiac total cavopulmonary connection. We were urged to carry out the surgical placement of an epicardial lead for an implantable cardioverter-defibrillator using a single coil transvenous shock lead through re-do midline sternotomy. Here we describe the details of this nontraditional surgical procedure for the placement of a lead for an implantable cardioverter-defibrillator in a case without venous access into the heart.

Effects of landiolol hydrochloride on intractable tachyarrhythmia after pediatric cardiac surgery.

BACKGROUND: While ß-blockers can be effective in controlling tachyarrhythmias after pediatric cardiac surgery, a negative inotropic influence sometimes complicates their use. Landiolol hydrochloride is a novel, ultra-short-acting ß-blocker recently developed in Japan. The drug has higher ß1:ß2 selectivity ratio and a less negative inotropic effect. This study retrospectively evaluates the efficacy and safety of landiolol in the management of tachyarrhythmias after pediatric cardiac surgery. METHODS: A retrospective analysis was performed on 312 consecutive patients undergoing surgery for congenital heart disease. Twelve patients were treated with landiolol for critical tachyarrhythmia. The mean age of patients was 28.7 ± 10.6 months. Five junctional ectopic tachycardia, 2 atrial flutters, 1 paroxysmal supraventricular tachycardia, 1 atrial fibrillation, 1 atrioventricular reciprocating tachycardia with Wolff-Parkinson-White syndrome and 2 excessive sinus tachycardia were treated. RESULTS: The mean loading and maintenance doses were 11.3 ± 4.0 and 6.8 ± 0.9 µg/kg per minute, respectively. Rate control was achieved in all patients. Landiolol reduced the heart rate from 169.7 ± 11.4 to 127.7 ± 7.5 beats per minute (p < 0.05) while blood pressure did not significantly change. Tachyarrhythmias were converted to sinus rhythm in 70.0% of the cases and the average time needed to achieve heart rate reduction was 2.3 ± 0.5 hours. CONCLUSIONS: Landiolol was efficacious in treating tachyarrhythmia in pediatric cardiac surgery. The desired negative chronotropic effect was achieved without significant hemodynamic compromise. The ultra-short half-life of landiolol provided rapid dose manipulation. This study suggests that landiolol is a promising option for the management of postoperative tachyarrhythmias in pediatric patients.

Tachycardia associated with twin atrioventricular nodes in an infant with heterotaxy and interruption of inferior vena cava.

We report a 12-month-old boy with heterotaxy and interruption of inferior vena cava who showed sustained tachycardia associated with twin atrioventricular nodes (AVNs). Atrioventricular reciprocating tachycardia with antegrade conduction through the posterior AVN and retrograde conduction through the anterior AVN were successfully ablated using an upper approach from the left internal jugular vein.

Comparison of PR intervals determined by fetal magnetocardiography and pulsed Doppler echocardiography.

OBJECTIVE: In clinical practice, measurement of mechanical PR interval (mPR) with pulsed Doppler echocardiography is a standard method used to estimate the atrioventricular conduction time in the fetus. However, fetal echocardiography does not directly reflect the electrical properties of the heart. Technological advances in fetal magnetocardiography (fMCG) have allowed recording of the electrical PR interval (ePR) with high time resolution. The aim of this study was to clarify the differences between ePR and mPR. METHODS: The study subjects were 295 normal human fetuses (gestational age, range 20.4-41.4 weeks) who underwent fMCG, and 135 of them underwent fetal echocardiography 15-90 min before or after fMCG. The ePR was measured using the fMCG, and the mPR was determined by two pulsed Doppler methods, simultaneous recording of the left ventricular inward and outward flow (LV in/out) (n = 135) and superior vena cava and ascending aorta (SVC/aAo) (n = 84). RESULTS: The ePR showed a significant, but weak, positive correlation with gestational age (r = 0.162, p = 0.0053). The mPR was significantly longer than the ePR (p < 0.0001), with mean differences of 14.6% (95% limits of agreement -10.7, 39.9) for the LV in/out method and 14.7% (95% limits of agreement -8.6, 38.0) for the SVC/aAo method. CONCLUSION: Our results point to the risk of overestimation of the atrioventricular conduction time when the mPR is used, and the need for careful interpretation of PR prolongation determined by mPR.

Staged repair of pentalogy of Cantrell with ectopia cordis and ventricular septal defect.

Pentalogy of Cantrell is a rare congenital anomaly characterized by a combination of severe defects in the middle of the chest and abdomen including intracardiac defects. Survival rate after cardiac surgery is extremely low. We present a successful staged complete repair of an omphalocele, a ventricular septal defect and a sternal defect in a case of pentalogy of Cantrell.

Focal atrial tachycardia originating from inside the inferior vena cava late after surgical repair of congenital heart defects.

An 11-year-old girl presented with focal atrial tachycardia (AT) originating from inside the inferior vena cava (IVC). Sustained AT appeared 10 years after surgical repair of the congenital heart defects. Focal AT was successfully eliminated with radiofrequency application at the earliest activation site, about 8 mm below the IVC right atrium junction. These findings suggested the existence of an electrically continuous myocardial extension in the IVC and a real risk of AT originating from IVC late after cardiopulmonary bypass with IVC cannulation.

Isolation of pulmonary vein and superior vena cava for paroxysmal atrial fibrillation in a young adult with left ventricular non-compaction.

We report a 19-year-old male patient with left ventricular non-compaction who presented with atrial fibrillation (AF) and ventricular tachycardia. Ventricular tachycardia was induced by AF with rapid ventricular response, but was prevented by electrical isolation of the pulmonary veins and superior vena cava.

A modification of extended aortic arch anastomosis augmented with subclavian flap aortoplasty for interrupted or hypoplastic aortic arch.

BACKGROUND: Surgical repair for hypoplastic aortic arch in neonates carries a substantial risk of recurrent obstruction. Simple arch anastomosis is not always a solution in cases of extended arch hypoplasia. We present our modified technique of extended aortic arch anastomosis augmented with subclavian flap aortoplasty. METHOD: We describe two neonates: interrupted aortic arch and transverse arch hypoplasia associated with aortic coarctation, who underwent a modification of extended aortic arch anastomosis augmented with subclavian flap aortoplasty. RESULTS: The patients recovered without any pressure gradient at the anastomotic site. Postoperative aortography showed no arch obstruction and they successfully underwent second stage repair. CONCLUSION: Our technique provides extensive augmentation of the aortic arch with a tension-free, wide and non-circumferential suture line which preserves potential for growth. The technique described may avoid persistent or repeat arch obstruction.

Coronary artery dilatation in LEOPARD syndrome. A child case and literature review.

LEOPARD syndrome (LS) is a rare inherited disease with multiple somatic abnormalities. LS and Noonan syndrome (NS) share many features, including cardiovascular disorders, and PTPN11 gene mutation is commonly reported in both syndromes. We report a 10-year-old male patient who was diagnosed as LS based on typical phenotypes including multiple lentigines, electrocardiographic abnormalities, ocular hypertelorism and deafness. Although the most prevalent cardiovascular abnormalities in LS are pulmonary stenosis and hypertrophic cardiomyopathy, diffuse bilateral dilatation of the coronary arteries was found on angiography in addition to apical hypertrophic cardiomyopathy in the present case. The vessels showed slight increases in diameter on angiography conducted at an interval of 6 years. A literature review identified several case reports describing coronary ectasia in patients with NS as well as LS. Considering both syndromes share the mutation of PTPN11 gene, coronary arterial involvement could be related to the gene aberration and should be screened even if the patient shows no symptoms of ischemic heart disease.