Catheter Ablation of Tachycardia Involving Twin/Single Atrioventricular Node in Patients With Right Isomerism.

AIMS: In addition to well-documented tachycardias involving twin atrioventricular (AV) nodes, tachycardias involving a single node have been clinically experienced in right atrial isomerism (RAI). This study aimed to characterize the AV node involvement patterns and evaluate the outcome of ablation therapy in RAI patients with tachycardias. METHODS: We retrospectively analyzed the medical records of 16 RAI patients who underwent catheter ablation of tachycardias involving twin or single AV nodes at our center between April 2006 and March 2020. RESULTS: A total of 22 ablation procedures were performed in 16 patients. The median age and body weight were 2 years (range 20 months-31 years) and 11.2 kg (range 7.4-42 kg), respectively. Two QRS complexes were confirmed in 11/16 patients, and a single QRS complex in 5/16. The dominant AV node was anterior in 7/16. Four patterns of tachycardias were identified: tachycardias reciprocating between two AV nodes with retrograde conduction through the anterior AV node (3/16) or through the posterior AV node (4/16); and reentrant tachycardias involving the anterior AV node only (3/16) or posterior AV node only (6/16). Ablation successfully eliminated the tachycardias in 15/16 patients (93.8%). Recurrence was reported in 7/16 (44%) during a median follow-up period of 96.5 months. Five of those 7 patients underwent additional ablation, and the tachycardias were eliminated in 3/5 patients. None of the patients developed ventricular asynchrony after ablation. CONCLUSION: Transcatheter ablation was effective in RAI patients with tachycardias involving twin or single AV nodes, and deterioration of the cardiac function was rare.

Valley Index as a Predictor of Prenatal Diagnosis of Total Anomalous Pulmonary Venous Connection.

INTRODUCTION: Total anomalous pulmonary venous connection (TAPVC) has a low prenatal diagnostic rate. Therefore, we investigated whether Doppler waveforms with a low pulsatility in the pulmonary veins can indicate fetal TAPVC. METHODS: This retrospective study included 16 fetuses with TAPVC, including 10 with complex congenital heart disease and 104 healthy fetuses that underwent fetal echocardiography. Pulmonary venous S and D wave flow velocities and the valley (representing the lowest velocity between the S and D waves) were measured. Valley indices I and II were then calculated as (velocity of valley/greater of the S and D wave velocities) and (velocity of valley/lesser of the S and D wave velocities), respectively. RESULTS: Supra/infracardiac TAPVC cases exhibited significantly greater valley indices than that of the healthy group. After adjusting for gestational age at fetal echocardiography, valley indices I (odds ratio [OR] 7.26, p < 0.01) and II (OR: 9.23, p < 0.01) were significant predictors of supra/infracardiac TAPVC. Furthermore, valley indices I and II exhibited a high area under the curve for detecting supra/infracardiac TAPVC, regardless of the presence of pulmonary venous obstruction. CONCLUSION: The valley index may be a useful tool for the detection of fetal TAPVC.

Successful ablation of premature ventricular contractions originating from the posterior-superior process of the left ventricle approaching from the right atrium in a 13-year-old male.

This is a case of a 13-year-old male with frequent premature ventricular contractions with QRS configurations of the left superior axis and left bundle branch block, which originated from the posterior-superior process of the left ventricle. Premature ventricular contractions were successfully eliminated by delivering radiofrequency energy to the inferior wall of the right atrium without causing either junctional rhythm or atrioventricular block. Ventricular arrhythmias originating from this site have been sporadically reported in adults; however, this is the first report in a child.

Successful perioperative management of pheochromocytoma in a patient with Fontan circulation.

Pheochromocytoma (PCC) can adversely affect Fontan circulation. However, there are few reports on its perioperative management before and after PCC resection in Fontan patients. A 24-year-old female patient with congenitally corrected transposition of the great arteries, ventricular septal defect, and pulmonary atresia who had undergone Fontan palliation developed heart failure caused by PCC. The patient was pre-conditioned for PCC resection with heart failure treatment, alpha-blocker titration, and careful infusion, and had a good intraoperative and postoperative course with no complications. Postoperative catheter data showed improvements in systemic vascular resistance, cardiac output, and central venous pressure compared with preoperative data. There is no established preconditioning method for PCC resection in patients with Fontan circulation. Careful perioperative management based on an understanding of the features of the Fontan circulation can lead to better outcomes. Learning objective: Pheochromocytoma (PCC) can occur in patients with Fontan circulation. Preoperative management and the PCC itself can adversely affect Fontan circulation, highlighting the importance of suspecting PCCs in Fontan patients based on symptoms such as heart failure, worsening arrhythmias, and headache, and emphasizing careful perioperative management.

Efficacy of SubcutAneous implantable cardioVErter-defibrillators in ≤18 year-old CHILDREN: SAVE-CHILDREN registry.

BACKGROUND: In adult patients, subcutaneous implantable cardioverter defibrillators (S-ICDs) have been reported to be non-inferior to transvenous ICDs with respect to the incidence of device-related complications and inappropriate shocks. Only a few reports have investigated the efficacy of S-ICDs in the pediatric field. This study aimed to investigate the utility and safety of S-ICDs in patients ≤18 years old. METHODS: This study was a multicenter, observational, retrospective study on S-ICD implantations. Patients <18 years old who underwent S-ICD implantations were enrolled. The detailed data on the device implantations and eligibility tests, incidence of appropriate- and inappropriate shocks, and follow-up data were assessed. RESULTS: A total of 62 patients were enrolled from 30 centers. The patients ranged in age from 3 to 18 (median 14 years old [IQR 11.0-16.0 years]). During a median follow up of 27 months (13.3-35.8), a total of 16 patients (26.2%) received appropriate shocks and 13 (21.3%) received inappropriate shocks. The common causes of the inappropriate shocks were sinus tachycardia (n = 4, 30.8%) and T-wave oversensing (n = 4, 30.8%). In spite of the physical growth, the number of suitable sensing vectors did not change during the follow up. No one had any lead fractures or device infections in the chronic phase. CONCLUSIONS: Our study suggested that S-ICDs can prevent sudden cardiac death in the pediatric population with a low incidence of lead complications or device infections. The number of suitable sensing vectors did not change during the patients' growth.

Control of Heart Rate in Infant and Child Tachyarrhythmia With Reduced Cardiac Function Using Landiolol (HEARTFUL)　- Results of a Prospective, Multicenter, Uncontrolled Clinical Study.

BACKGROUND: The prospective Control of HEART rate in inFant and child tachyarrhythmia with reduced cardiac function Using Landiolol (HEARTFUL) study investigated the effectiveness and safety of landiolol, a short-acting ß1 selective blocker, in children.Methods and Results: Twenty-five inpatients aged ≥3 months to <15 years who developed supraventricular tachyarrhythmias (atrial fibrillation, atrial flutter, supraventricular tachycardia, and inappropriate sinus tachycardia) were treated with landiolol. The primary endpoint, the percent of patients with a reduction in heart rate ≥20% from the initial rate of tachycardia, or termination of tachycardia at 2 h after starting landiolol, was achieved in 12/25 patients (48.0%; 95% CI 28.4-67.6), which exceeded the predetermined threshold (38.0%). At 2 h after starting landiolol administration, heart rate had decreased by ≥20% in 45.8% (11/24) and recovery to sinus rhythm was achieved in 40.0% (6/15) of the patients. Adverse reactions (ARs) occurred in 24.0% (6/25) of patients, and the study was discontinued in 4.0% (1/25) of the patients; however, none of these ARs were considered serious. The most common AR was hypotension (20.0% [5/25] of patients). CONCLUSIONS: The HEARTFUL study has demonstrated the efficacy of landiolol, by reducing heart rate or terminating tachycardia, in pediatric patients with supraventricular tachyarrhythmias. Although serious ARs and concerns were not identified in this study, physicians should be always cautious of circulatory collapse due to hypotension.

Agenesis of the venous duct with abnormal return of the umbilical vein into the superior vena cava: A case report.

INTRODUCTION: Agenesis of the venous duct is rare, with an incidence rate of .04%-.6%. Abnormal drainage of the umbilical vein (UV) to superior vena cava (SVC) is seen in .5% of agenesis of the venous duct cases. We present a case of agenesis of the venous duct with drainage of the UV into the SVC accompanied by tetralogy of Fallot. CASE PRESENTATION: The fetus was diagnosed with agenesis of the venous duct and tetralogy of Fallot at 29 gestational weeks. The UV directly returned to the SVC. Cardiomegaly and pericardial effusion were observed but did not deteriorate. The female infant was born at 40 gestational weeks. Contrast-enhanced computed tomography showed that the UV was occluded at its proximal aspect. No abnormality of the portal system was noted. The infant underwent intracardiac repair and was doing well at 16 months of age. DISCUSSION/CONCLUSION: Although the extrahepatic drainage type of agenesis of the venous duct is occasionally associated with heart failure and hydrops, severe hydrops was absent in this case. It was speculated that vascular resistance in the long pathway to the SVC restricted direct inflow from the UV. Portosystemic shunts and agenesis of the portal system are reported complications of agenesis of the venous duct. Prenatal agenesis of the venous duct diagnosis may be crucial for early postnatal diagnosis of these conditions.

Absent pulmonary valve with tricuspid atresia/stenosis: literature review with new three long-term cases.

Absent pulmonary valve (APV) syndrome with tricuspid atresia or tricuspid stenosis (TA/TS) is an extremely rare malformation recently reported as a variant of APV with intact ventricular septum (VS). The condition, however, has univentricular physiology and unique structural and clinical features. The purpose of this study was to update the current knowledge about this condition by describing long-term outcomes of three new cases and reviewing the available literatures. A systematic literature search was performed to collect clinical and anatomical data of APV with TA/TS. Institutional medical records were retrospectively reviewed to identify APV with TA/TS patients. In a total of 62 (59 reported and 3 new) cases, patent ductus arteriosus was present in 98% of APV patients with TA/TS. A large ventricular septal defect, dilatation of the pulmonary arteries, which is typically found in APV with tetralogy of Fallot, and respiratory distress at birth were rarely reported. Most of the recent cases were successfully managed by the Glenn or Fontan procedure. Coronary artery anomaly and ventricular arrhythmia were more frequently reported as the cause of death or severe neurological sequelae (9/16 and 3/8, respectively). Additional surgical intervention was required in the mid/long-term period in three cases due to left-ventricular outflow obstruction and in two due to aortic dilatation. The Fontan and Glenn procedures improved the survival in the last two decades. In addition to coronary artery anomaly and ventricular arrhythmia, left-ventricular outflow tract obstruction and aortic dilatation should be carefully monitored.

A double-barrelled aorta with high aortic Arch.

A double-barrelled aorta was detected in a female newborn with 22q11.2 deletion syndrome. Double-barrelled aorta had been previously described as persistence of the fifth pharyngeal arch, but its existence continues to be debated. Recent embryologic studies suggest that double-barrelled aorta is more likely explained by other developing processes in the majority of cases. In our case, catheter angiography confirmed the presence of the high aortic arch and double-barrelled aorta. The upper lumen was located above the level of the clavicles. These findings suggested that the persistence of the segment of dorsal aorta between the third and fourth embryonic arches and the double-barrelled aorta was more likely a consequence of persistence of the third and fourth pharyngeal arches. Detailed imaging and embryologic considerations played an important role in accurate assessment of the origin of the double-barrelled aorta. .

Platelet count and abdominal dynamic CT are useful in predicting and screening for gastroesophageal varices after Fontan surgery.

OBJECTIVE: Patients who undergo Fontan surgery for complex cardiac anomalies are prone to developing liver and gastrointestinal complications. In particular, gastroesophageal varices (GEVs) can occur, but their prevalence is unknown. We aimed to elucidate the occurrence of GEVs and the predicting parameters of GEVs in these patients. MATERIALS AND METHODS: Twenty-seven patients (median age, 14.8 years; median time since surgery, 12.9 years) who had undergone the Fontan surgery and were examined by abdominal dynamic computed tomography (CT) for the routine follow-up were included in the study. Radiological findings including GEVs and extraintestinal complications were retrospectively evaluated by experienced radiologists in a blinded manner. Relationships between blood-biochemical and demographic parameters and the presence of GEVs were statistically analyzed. RESULTS: Dynamic CT revealed gastric varices (n = 3, 11.1%), esophageal varices (n = 1, 3.7%), and gastrorenal shunts (n = 5, 18.5%). All patients with gastric varices had gastrorenal shunts. All gastric varices were endoscopically confirmed as being isolated and enlarged, with indications for preventive interventional therapy. A platelet count lower than 119 × 109 /L was identified as a predictor of GEV (area under the receiver operating curve, 0.946; sensitivity, 100%; and specificity, 87%). CONCLUSIONS: GEVs are important complications that should not be ignored in patients who have undergone a Fontan procedure. Platelet counts lower than 119 × 109 /L may help to prompt patient screening by using abdominal dynamic CT to identify GEVs and their draining collateral veins in these patients.

Prenatally diagnosed left atrial appendage aneurysm with various postnatal imaging investigations: A case report.

A congenital left atrial appendage aneurysm (LAAA) is a rare cardiac malformation, that is, usually diagnosed in adulthood. It is rarely diagnosed prenatally. In most cases, surgical resection is recommended soon after the diagnosis has been made due to the risk of arrhythmia and thrombotic events. The present report describes a case of LAAA that was prenatally diagnosed and was asymptomatic postnatally. Imaging revealed the relation of the cardiac and airway structures around the LAAA in detail. The patient underwent surgical resection of the LAAA successfully at 7 months of age and is currently healthy at 5 years of age.

Assessing liver stiffness with conventional cut-off values overestimates liver fibrosis staging in patients who received the Fontan procedure.

AIM: Patients who undergo the Fontan procedure for complex congenital heart disease are prone to liver cirrhosis. Liver stiffness (LS) reflects liver fibrosis stage in patients with chronic viral hepatitis; however, its accuracy in predicting liver fibrosis stage in Fontan patients is controversial. We aimed to clarify the correlation between LS and liver fibrosis stage in Fontan patients. METHODS: Fifty-eight Fontan patients were prospectively measured for LS with transient elastography. We undertook liver biopsy, cardiac catheterization, and laboratory tests in 22 of these patients (median age, 14.7 years; range, 9.9-32.1 years) with LS > 11.0 kPa (median, 19.2 kPa; range, 12.2-39.8 kPa); these elevated LS values suggest liver cirrhosis. RESULTS: Histologically, all patients showed mild-to-severe portal and sinusoidal fibrosis but no cirrhosis. Statistically, LS did not predict histological liver fibrosis scores (p = 0.175). Liver stiffness was not correlated with central venous pressure (p = 0.456) or with the hepatic venous pressure gradient (HVPG; p = 0.062), although the p value for HVPG was only slightly above the threshold for significance. CONCLUSIONS: Fontan patients are prone to developing both portal and sinusoidal fibrosis. Liver stiffness could be influenced by HVPG, and using the conventional cut-off values for LS overestimates and overtreats liver fibrosis in these patients.

Catheter ablation in children and patients with congenital heart disease: Review of 1021 procedures at a high-volume single center in Japan.

BACKGROUND: Although pediatric catheter ablation therapy has often been described, few reports on outcomes in a large series of patients at a single center are available. OBJECTIVE: The purpose of this study was to evaluate arrhythmia substrates, outcomes, and complications of catheter ablation in children and patients with congenital heart disease (CHD) performed at a single center. METHODS: We retrospectively analyzed all pediatric patients <18 years and patients of all ages with CHD who underwent ablation therapy between June 2006 and May 2018. RESULTS: A total of 1021 ablation procedures were performed in 877 patients (median age 12.5 years; range 2 months to 67 years). This cohort included 152 CHD patients, 90 small patients (<15 kg), and 14 infants (<1 year). The most frequent indication was Wolff-Parkinson-White pattern (WPW) (n = 287 [32.7%]). Of the 55 patients with asymptomatic WPW, 40 patients (72.7%) had retrograde accessory pathway conduction. Overall success and recurrence rates were 93.5% and 17.3%, respectively. Small patients and CHD patients had lower success rates. No deaths occurred. Serious complications occurred in 5 patients. CONCLUSION: Catheter ablation is safe and effective for treatment of arrhythmia in pediatric and CHD patients. However, ablation was less successful in small patients and CHD patients. The risk of complications was similar to those previously reported for catheter ablation in pediatric, CHD, and adult patients.

A rare case of truncus arteriosus Van Praagh type A3: Prenatal diagnosis and postnatal management.

Truncus arteriosus (TrA) type A3, according to the Van Praagh (VP) classification, cannot be classified under the Collett and Edwards (C-E) system. In this rare anomaly, postnatal closure of the ductus arteriosus can cause unilateral pulmonary artery obstruction; hence, prenatal diagnosis and early confirmatory postnatal diagnosis are important. This case was referred to our hospital for suspected fetal heart disease at 29 weeks' gestation. TrA C-E type 1 was diagnosed by fetal echocardiography, with a right-sided aortic arch, absent inferior vena cava, and azygos continuation. The neonate was delivered vaginally at 41 weeks' gestation. Postnatal echocardiography showed a right-sided aortic arch with the right pulmonary artery originating from the common arterial trunk and the left pulmonary artery originating from the brachiocephalic artery. The diagnosis was TrA VP type A3, with a right-sided aortic arch and left-sided ductus arteriosus. Patency of the left-sided ductus arteriosus was maintained with prostaglandin E1.alpha-cyclodextrin. Right pulmonary artery banding was performed 3 days after birth. The Rastelli procedure was performed when the patient was 2 months old and weighed 4.2 kg. Delayed diagnosis of VP type A3 can cause unilateral pulmonary artery disconnection; hence, timely and accurate diagnosis is warranted to ensure stable disease management. .