Focal atrial tachycardia originating from the pulmonary vein with onset later than 3 years of age might have a better prognosis, possibly converting in adolescence.

Two cases of focal atrial tachycardia probably originating from the pulmonary vein with onset later than 3 years of age are presented. Both cases had associated variable atrioventricular conduction and showed no signs of heart failure, and they converted to sinus rhythm at the time of puberty. In cases of focal atrial tachycardia originating from the pulmonary vein with onset later than 3 years of age, drug therapy may be effective. Even if drug therapy is not effective, changes in the autonomic nervous system are reflected strongly in the pulmonary veins, so that changes in autonomic nervous system regulation with growth might terminate focal atrial tachycardia. Therefore, focal atrial tachycardia originating from the pulmonary vein with onset later than 3 years of age might have a better prognosis.

Cesium-137 stored on and discharged from banks of an agricultural canal in Iitate, Fukushima.

This study aimed to investigate the dynamics of 137Cs around banks along an agricultural canal for paddy fields in Iitate, Fukushima, Japan. Five plots (2.4-12.6 m2) on the banks were monitored intermittently during six time periods from May 2018 to November 2019. We directly collected runoff water samples discharged from the banks followed by partitioning it into particulate and dissolved fractions and determining 137Cs in them. To investigate the source of 137Cs in the runoff water, we sequentially extracted 137Cs in various chemical forms from litter samples collected on the banks. The results showed that the discharge rates of the dissolved 137Cs per unit area from the plots were lower than those observed at the downstream of the agricultural canal, whereas more than 50% of the 137Cs discharged from the plots was in the dissolved fraction. Moreover, the results indicate that 137Cs stored in the standing plants and the litter was the primary source of the dissolved 137Cs discharged into the agricultural canal. The concentrations of the water-soluble 137Cs in the litter per plot area may have been retained by the sufficiently higher concentrations of 137Cs in litter in other chemical forms and those in the standing plants, which are the source of the litter.

The mid-term outcome of Fontan conversion compared with primary total cavopulmonary connection.

BACKGROUND: The indication of Fontan conversion (FC) from atriopulmonary connection (APC) to total cavopulmonary connection (TCPC) is unclear. We sought to analyze the mid-term outcome of prophylactic and therapeutic Fontan conversion compared with that of primary TCPC. METHODS: Patients with a univentricular heart who underwent cardiac catheterization at >18 years of age between July 2005 and July 2019 were included and divided into three groups: symptomatic APC patients who underwent therapeutic FC (t-FC, n = 13), asymptomatic APC patients after prophylactic FC (p-FC, n = 15), and patients who had primary TCPC procedure (pTCPC, n = 24). RESULTS: The mean last follow up was at the age of 32.0 ± 7.8, 26.8 ± 3.8, and 27.3 ± 7 years (p = 0.07) in t-FC, p-FC, and pTCPC, respectively. There was no late death. All of t-FC and 12 (80%) of p-FC cases underwent concomitant arrhythmic surgery. Consequently, five and four patients in t-FC and p-FC groups required pacemaker implantations mostly due to sinus node dysfunction. Thromboembolism was seen in 2 cases in both t-FC (15%) and p-FC (13%), and 1 case in pTCPC (4%) (p = 0.50). The last cardiac catheterization was performed at the age of 29.5 ± 8.5, 24.6 ± 3.8, and 26.3 ± 7.1 years (p = 0.11) in t-FC, p-FC, and pTCPC patients, respectively. There was no significant difference in central venous pressure, aortic pressure, and cardiac index among the three groups. There was no late supraventricular tachyarrhythmic event seen in t-FC and p-FC, whereas two patients in pTCPC had newly developed atrial flutter. CONCLUSIONS: FC is a safe and feasible procedure to bring APC patients back onto the same track of primary TCPC patients in terms of hemodynamics as well as arrhythmia. The antiarrhythmic procedure should be carefully chosen because sinus node dysfunction can frequently occur and FC itself would reduce the risk of arrhythmia.

Influence of Percutaneous Occlusion of Atrial Septal Defect on Left Atrial Function Evaluated Using 2D Speckle Tracking Echocardiography.

Percutaneous occlusion of atrial septal defect (ASD) has recently become a standard therapeutic strategy, but little is known about left atrial (LA) function thereafter. The present study aimed to determine LA function in 43 children with ASD and 13 controls based on LA strain measured by two-dimensional echocardiographic speckle tracking (2DE-ST). Among these children, 12 underwent surgery (ASD-S), 31 had device closure (ASD-D), and 13 were included as controls. LA strain was significantly decreased after ASD-D but was not significantly altered after ASD-S, indicating that percutaneous occlusion of an ASD might decrease LA function. Furthermore, the size of the ASD device negatively correlated with LA strain. These results imply that ASD occlusion devices negatively influence LA function and might be important when decided therapeutic strategies for ASD. LA strain measured by 2DE-ST should become a good indicator of LA function after ASD treatment in children.

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.

Atropine-induced monomorphic ventricular tachycardia in an adolescent: A rare case.

A 13-year-old girl had a history of episodic palpitations lasting for approximately 5 min since the first grade of junior high school. She was noticed to have tachycardia during auscultation at a school-based health screening program. Since non-sustained ventricular tachycardia of the left bundle branch block type was induced by a triple master exercise load at a local doctor's clinic, she was referred to our pediatric cardiology department for further management. Tachycardia could not be induced by programmed stimulation in an electrophysiological study, although ventricular tachycardia was induced by atrial high frequency pacing with intravenous injection of atropine under continuous isoproterenol infusion. .

Elevation of Serum Acid Sphingomyelinase Activity in Children with Acute Respiratory Syncytial Virus Bronchiolitis.

Acid sphingomyelinase (ASM) is a lysosomal enzyme that hydrolyzes sphingomyelin into ceramide, a bioactive lipid to regulate cellular physiological functions. Thus, ASM activation has been reported as a key event in pathophysiological reactions including inflammation, cytokine release, oxidative stress, and endothelial damage in human diseases. Since ASM activation is associated with extracellular ASM secretion through unknown mechanisms, it can be detected by recognizing the elevation of secretory ASM (S-ASM) activity. Serum S-ASM activity has been reported to increase in chronic diseases, acute cardiac diseases, and systemic inflammatory diseases. However, the serum S-ASM has not been investigated in common acute illness. This study was designed to evaluate serum S-ASM activity in children with common acute illness. Fifty children with common acute illness and five healthy children were included in this study. The patients were categorized into five groups based on clinical diagnoses: acute respiratory syncytial virus (RSV) bronchiolitis, adenovirus infection, streptococcal infection, asthma, and other infections due to unknown origin. The serum S-ASM activity was significantly elevated at 6.9 ± 1.6 nmol/0.1 mL/6 h in the group of acute RSV bronchiolitis patients compared with healthy children who had a mean level of 1.8 ± 0.8 nmol/0.1 mL/6 h (p < 0.05). In the other illness groups, the serum S-ASM activity was not significantly elevated. The results suggest an association of ASM activation with RSV infection, a cause for common acute illness. This is the first report to describe the elevation of serum S-ASM activity in respiratory tract infection.

Feasibility and safety of transseptal puncture procedures for radiofrequency catheter ablation in small children weighing below 30 kg: single-centre experience.

AIMS: Transseptal puncture (TSP) has become a common approach in catheter ablation of arrhythmia originating from the left atrium. In paediatric patients, however, TSP can be a challenge due to narrower access vessels and small left atrial size, and the safety of TSP in smaller children is yet to be understood. The purpose of this study was to retrospectively evaluate the feasibility and safety of TSP in children weighing below 30 kg. METHODS AND RESULTS: Among 655 paediatric patients who underwent catheter ablation of arrhythmia between July 2009 and April 2015, 43 cases having structurally normal hearts, weighing <30 kg and requiring TSP were included in the study. Age, height, body weight, diagnosis, and complications during TSP and catheter ablation were evaluated. The median age, height, and body weight (range) were 7.0 years (0.3-11.1), 116.8 cm (54.0-138.4 cm) and 21.5 kg (4.3-29.6 kg), respectively. Diagnosis included manifest (n = 27; 62.8%) and concealed accessory pathway (n = 14; 32.6%) and atrial tachycardia (n = 2; 4.6%). In 10 cases (23.2%), TSP using radiofrequency energy was performed. None of the patients had major complications. Pericardial effusion was recorded as a minor complication in one patient (2.3%). CONCLUSION: TSP was feasible, safe, and of low risk of complications in children weighing <30 kg.

Radiofrequency catheter ablation of idiopathic left anterior fascicular ventricular tachycardia in children.

BACKGROUND: Idiopathic ventricular tachycardia of left anterior fascicular origin (IVT-LAF) is a rare condition, and radiofrequency catheter ablation (RFCA) therapy has not been reported in children. OBJECTIVE: This study aimed to evaluate the procedures and outcomes of RFCA for pediatric IVT-LAF. METHODS: Pediatric IVT-LAF cases for which RFCA was performed between June 2006 and May 2012 at our hospital were reviewed. RESULTS: Of 537 pediatric cases of RFCA, 6 had IVT-LAF; 4 had anterior fascicular involvement only, while 2 had both anterior and posterior fascicular involvement. All 6 of them underwent RFCA at the median age of 8.8 years (range 4.3-14.3 years). RFCA was successful in all patients, but 4 had recurrence and underwent 1-3 additional sessions of RFCA. In a total of 10 RFCA sessions, the overall recurrence rate was 50%. The site of RFCA was determined on the basis of detection of diastolic potential during ventricular tachycardia (7 sessions) or isolated delayed potential during sinus rhythm (1) or by pace mapping (2). During the median follow-up period of 33 months, no further recurrence was reported except for 1 patient, who had a recurrence and was scheduled for additional session at the time of this report. Major complications included 1 case of complete atrioventricular block and 1 case of complete left bundle branch block. CONCLUSION: Despite a high recurrence rate and a few complications, RFCA of the site of isolated delayed potential or diastolic potential, if applied cautiously, is a possible treatment of choice for pediatric IVT-LAF.

Differentiating fasciculoventricular pathway from Wolff-Parkinson-White syndrome by electrocardiography.

BACKGROUND: In school-based cardiovascular screening programs in Japan, Wolff-Parkinson-White (WPW) syndrome is diagnosed based on the presence of an electrocardiographic (ECG) delta wave without differentiation from the fasciculoventricular pathway (FVP), although the risk of sudden death is associated only with the former. OBJECTIVE: The purpose of this study was to differentiate FVP patients among children diagnosed with WPW syndrome by ECG. METHODS: Children who were diagnosed with WPW syndrome through school screening between April 2006 and March 2008 and had QRS width ≤120 ms were included. Patients with asthma and/or coronary heart disease were excluded. FVP and WPW syndrome were differentiated based on ECG responses to adenosine triphosphate (ATP) injection. Age, PR interval, QRS width, and Rosenbaum classification were compared among patients. RESULTS: Thirty patients (median age 12.7 years, range 6.5-15.7 years) participated in the study. FVP was diagnosed in 23 patients (76.7%), and WPW syndrome in 7 (23.3%). In Rosenbaum type A patients, all six patients had WPW syndrome, whereas FVP was diagnosed in 23 of 24 and WPW syndrome was diagnosed in 1 of 24 of type B patients. Age, PR interval, and QRS width were not significantly different between the two conditions. CONCLUSION: ATP stress test was reliable in differentiating FVP from WPW syndrome. Although FVP is considered rare, the results of our study indicate that many WPW syndrome patients with QRS width ≤120 ms may actually have FVP. Patients categorized as type B are more likely to have FVP, whereas type A patients are most likely to have WPW syndrome.

[Association of lung volume with shunt size in Starnes' procedure in neonates with severe Ebstein's anomaly].

Our modification of Starnes' procedure reduces right ventricular volume using only "suture plication" to improve surgical outcomes. However, shunt size in the procedure varies widely between patients. As this may be related to small lung volume, we estimated lung volume in each patient using computed tomography (CT).Since 2007, we have performed Starnes' procedure in 4 patients. Preoperative cardiothoracic ratio was 89±4.5%. Age and body weight at operation were 4.3±2.6 days and 2.6±0.2 kg, respectively. Anatomic slices 3 mm thick were acquired in transverse planes by CT. Total lung volume was calculated by accumulating those slices. Total lung volume and lung volume/body weight were 97.2±34.1 ml, 36.8±11.5 ml/kg, respectively. In one patient, a 3 mm prosthetic graft was needed to place a clip to regulate blood flow. Another patient required an additional shunt. The patient with the smallest lung volume required treatment with an extracorporeal lung-assistance device. Chest X-rays of neonates with severe Ebstein's anomaly usually show a "wall-to-wall" heart. However, lung volume varies widely between patients. Estimation of lung volume using CT is useful. In patients with smaller lung volume, a larger shunt than usual may be required to obtain the necessary pulmonary blood flow.