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Background: Few epidemiologic data on the gender differences among patients with accessory atrioventricular pathways have been reported. Objective: The purpose of this study was to investigate the explicit gender differences in electrophysiologic characteristics among patients with accessory atrioventricular pathways. Methods: A total of 1,821 consecutive patients with accessory atrioventricular pathways were referred to our institution for electrophysiologic study and radiofrequency catheter ablation. A detailed electrophysiologic study was performed in all patients. Results: Patient age at onset of atrioventricular reentrant tachycardia was 43 ± 17 years. There were 1,117 males (61.3%) with accessory atrioventricular pathways. Men had more manifest and left-sided but fewer multiple accessory pathways. Men had more antidromic atrioventricular reentrant tachycardia. Men had a shorter anterograde accessory pathway effective refractory period (ERP) and a higher prevalence of an anterograde accessory pathway ERP (<250 ms). Men with accessory atrioventricular pathways had a longer atrioventricular nodal ERP and atrial ERP and a shorter ventricular ERP. Conclusion: Gender differences in the clinical and electrophysiologic characteristics of patients with accessory atrioventricular pathways could be closely linked and may imply a different pathogenesis. [ABSTRACT FROM AUTHOR]

Background: Right ventricular outflow tract obstruction relief is one of the major procedures during the total correction of tetralogy of Fallot (TOF). Pulmonary insufficiency (PI) is usually inevitable after a transannular incision with a patch repair is performed. Therefore, some surgeons advocate to place a monocusp valve within the transannular patch (TAP) in order to decrease the severity of the PI. However, the monocusp valve seemed not be very effective in some patients who underwent the complete TOF repair., Methods: Patients who had the classic form of TOF between January 2009 and January 2017 and underwent the corrective surgery with a TAP by the same cardiovascular surgeon were identified for further analysis. Clinical information including demographics at operation, perioperative data, and postoperative outcome were collected retrospectively and compared between the group with and without a monocusp valve., Results: A total of 24 TOF cases were included in the final analysis, and 16 (66.7%) patients received a monocusp valve placement. The patients' characteristics before and during the surgery were similar between the two groups. The median duration of chest tube drainage after the total correction in the monocusp group was longer than those without the valve (p = 0.04). There was no difference in the immediate postoperative data, including the inflammation/infection status, the duration of mechanical ventilation, and the length of ICU and hospital stay., Conclusion: Implantation of a monocusp valve during the total TOF correction using a TAP did not bring benefit to improve the immediate postoperative outcomes, especially the duration of the pleural drainage. Further study with a prospective design and a larger number of cases is needed., Competing Interests: Conflicts of interest: The authors declare that they have no conflicts of interest related to the subject matter or materials discussed in this article., (Copyright © 2021, the Chinese Medical Association.)

Background: The location of the accessory pathway (AP) can be precisely identified on surface electrocardiography (ECG) in adults with Wolff-Parkinson-White (WPW) syndrome. However, current algorithms to locate the AP in pediatric patients with WPW syndrome are limited., Objective: To propose an optimal algorithm that localizes the AP in pediatric patients with WPW syndrome., Methods: From 1992 to 2016, 180 consecutive patients aged below 18 years with symptomatic WPW syndrome were included. After the exclusion of patients with non-descriptive electrocardiography (ECG), multiple APs, congenital heart diseases, non-inducible tachycardia, and those who received a second ablation, 104 patients were analyzed retrospectively. Surface ECG was obtained before ablation and evaluated by using previously documented algorithms, from which a new pediatric algorithm was developed., Results: Previous algorithms were not highly accurate when used in pediatric patients with WPW syndrome. In the new algorithm, the R/S ratio of V1 and the polarity of the delta wave in lead I could distinguish right from the left side AP with 100% accuracy. The polarity of the delta wave of lead V1 could distinguish free wall AP from septal AP with an accuracy of 100% in left-side AP, compared to 88.6% in leads III and V1 for right-side AP. The overall accuracy was 92.3%., Conclusions: This simple, novel algorithm could differentiate left from right AP and septal from free wall AP in pediatric patients with WPW syndrome.

The present study investigated the incidence and predictors of permanent pacemaker (PPM) implantation for late atrioventricular block (AVB) in patients with atrioventricular nodal reentrant tachycardia (AVNRT) who received ablation. The data from 3,442 patients with AVNRT who received ablation were analyzed. Those who developed late AVB (>1 month after ablation) and received a PPM were identified. The incidence of PPM implantation in 1,148 matched patients with Wolff-Parkinson-White syndrome and in the whole population of Taiwan were compared. Of the patients with AVNRT receiving ablation (mean follow-up duration 128.3 ± 62.5 months), 15 (0.4%) received PPM implantation for late AVB (mean interval after catheter ablation 95.4 ± 55.0 months). Only age (odds ratio 1.05, p = 0.02) and transient AVB (odds ratio 8.55, p = 0.01) during the procedure were independently associated with PPM implantation for late AVB. The patients with AVNRT had a greater incidence of PPM implantation due to late AVB compared to the matched patients with Wolff-Parkinson-White syndrome. The annual incidence of PPM implantation for AVB was also greater in the patients with AVNRT than in the general population. In conclusion, the incidence of PPM implantation for late AVB in patients with AVNRT who received catheter ablation was low but still greater than that in patients with Wolff-Parkinson-White syndrome and the general population in Taiwan., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: The bacillus Calmette-Guérin (BCG) reaction is not included in the classical clinical criteria for Kawasaki disease (KD). However, a reaction at the BCG inoculation site has been mentioned among the "other clinical findings" that are present in about 30-50% of KD patients. The objective of this study was to investigate the clinical characteristics of KD patients with reactions at the BCG inoculation site., Methods: A retrospective study of all patients diagnosed with KD between September 2000 and August 2010 was performed. The clinical presentations, laboratory results, treatment outcomes, and coronary artery abnormalities in the BCG-reactive [BCG(+)] and BCG-nonreactive [BCG(-)] groups were analyzed and compared., Results: In total, 145 patients with KD diagnosed at our institution were included; 46 (31.7%) had a reaction at the BCG inoculation site. The BCG(+) group was younger than the BCG(-) group. Laboratory results showed higher white blood cell counts, platelet counts, and serum potassium levels, and lower low-density lipoprotein levels in the BCG(+) group. The BCG(+) group had a shorter fever duration before intravenous immunoglobulin treatment and a shorter total fever duration than the BCG(-) group. Multivariable logistic regression analysis showed that the age at diagnosis was the only factor significantly associated with a reaction at the BCG inoculation site in KD patients., Conclusions: In countries with a national BCG vaccination program, a reaction at the BCG inoculation site could be a useful and early diagnostic sign of KD among younger patients, especially those younger than 6 months., (Copyright © 2012. Published by Elsevier B.V.)

Conjoined twins are a rare congenital anomaly with an estimated incidence of 1/50,000 to 1/100,000. Among thoracopagus conjoined twins, 75% have a fused heart. We compare the usefulness of various modalities for evaluating cardiovascular structure in fused-heart conjoined twins. We report a series of 20 sets of thoracopagus conjoined twins as well as the results of a PubMed database literature review literature from 1982 to 2009. Twenty sets of fused-heart thoracopagus conjoined twins were evaluated by echocardiography, cardiac catheterization, magnetic resonance image (MRI), and three-dimensional computed tomography angiography (3D-CTA). Imaging results were compared to findings at surgery or autopsy. All sets of conjoined twins underwent postnatal echocardiography; 11 sets (55%) underwent cardiac catheterization; 4 sets (20%) underwent MRI; and 1 set (5%) underwent 3D-CTA. All intracardiac anatomy (ICA) was identified by echocardiography. Cardiac catheterization, MRI, and 3D-CTA were able to identify extracardiac vascular structures as well as the ICA. 3D-CTA, which can be performed as early as the first week of life, is a noninvasive, less expensive, and the safe examination with minimal risk due to its short procedural time. Three-dimensional CTA is an effective and safe modality for evaluating the cardiovascular anatomy of fused-heart conjoined twins before surgery.

Background: Multidetector-row computed tomographic (MDCT) coronary angiography has been validated for noninvasive assessment of coronary anatomy. However, we have less experience in diagnosing children with congenital or acquired coronary artery abnormalities by MDCT. We compared the results of MDCT with invasive coronary angiography (ICA) on identifying coronary abnormalities in infants, children, and adolescents with coronary artery abnormalities, including aneurysm, coronary fistula, or anomalous left coronary artery from pulmonary artery (ALCAPA)., Methods: From January 2002 to December 2009, patients with congenital or acquired coronary abnormalities underwent either ICA, MDCT, or both studies for assessment of coronary anatomy. We reviewed all patients' clinical diagnosis, coronary abnormalities identified by MDCT or ICA, and analyzed the advantages and disadvantages between those two methods., Results: Thirty-three patients (20 males and 13 females) with a mean age of 10.3 years (range: 18 days to 25 years) had coronary abnormalities, including coronary artery aneurysm in Kawasaki disease (n=15), coronary artery fistula (n=12), myocardial bridge (n=2), and ALCAPA (n=4). In 17 patients only referred for ICA, 5 coronary aneurysms (3 on left main coronary artery, 1 on left anterior descending artery segment proximal, 1 on right coronary artery segment proximal), 11 coronary artery fistulas, and 2 ALCAPAs were detected. Sixteen patients received MDCT study, and 14 coronary artery aneurysms (4 on right coronary artery, 5 on left main coronary artery, 4 on left anterior descending artery, 1 on left circumflex artery), 3 myocardial bridges, 1 coronary artery fistulas, and 2 ALCAPAs were assessed. Ten patients with Kawasaki disease-related coronary lesions received MDCT study, and totally 102 (78.5%) segments permitted visualization with accurate diagnostic image quality. In this study, there were 11 patients with indication for conventional ICA spared invasive angiography after precise assessment by MDCT., Conclusion: We conclude that MDCT is a good and useful modality for assessment of congenital or acquired coronary abnormalities in pediatric patients. However, MDCT cannot replace invasive cardiac catheterization and ICA because of lack of therapeutic role., (2011, Taiwan Pediatric Association. Published by Elsevier Taiwan LLC. All rights reserved.)

Newborn screening for Fabry disease in Taiwan Chinese has revealed a high incidence of the late-onset GLA mutation IVS4 + 919G→A (∼1 in 1,500-1,600 males). We studied 94 adults with this mutation [22 men, 72 women; mean age: men 57.8 ± 6.0 (range 42-68), women 39.1 ± 14.1 years (range 19-82)]. Plasma α-galactosidase A activity assay was 10.4 ± 11.2% of normal in the men and 48.6 ± 19.5% of normal in the women. Echocardiography in 90 of the adults revealed left ventricular hypertrophy (LVH) in 19 (21%), including 14 of 21 men (67%) and 5 of 69 women (7%). Microalbuminuria, based on the urine albumin-to-creatinine ratio measured on at least two occasions, was present in 17 of 86 subjects (20%) (men: 5/20, 25%; women 12/66, 18%). At least one ocular manifestation consistent with Fabry disease was present in 41 of 52 subjects (79%) who underwent ophthalmologic examination, including 8 (15%) with conjunctival vessel tortuosity, 15 (29%) with cornea verticillata, 10 (19%) with Fabry cataract, and 34 (65%) with retinal vessel tortuosity. Among subjects over 40 years of age, men were more likely than women to have LVH [14/21 (67%) vs 5/25 (20%), p < 0.001]. Cardiovascular, renal and ocular abnormalities are highly prevalent in adult Taiwan Chinese subjects with the Fabry mutation IVS4 + 919G→A. Our findings contribute to the limited understanding of the course of this late-onset disease variant and underscore the need for close follow up in such patients.

Previous studies have reported that increased high-sensitive C-reactive protein (hs-CRP) levels are associated with an inflammatory state. This study investigated the association among hs-CRP, substrate properties, and long-term clinical outcomes after catheter ablation of atrial fibrillation (AF). A total of 137 patients with AF (54 +/- 13 years) who underwent mapping and catheter ablation were included. The hs-CRP was measured before the first ablation procedure. The substrate properties (initiating triggers, biatrial mean voltage, and high-frequency sites) of the 2 atria and long-term outcome were investigated in patients in the low hs-CRP group (<75%, 2.92 mg/L) and high hs-CRP group (>75%, 2.92 mg/L). Patients with a higher hs-CRP were associated with an increased number of identified nonpulmonary vein ectopies (34.4% vs 17%, p = 0.034), lower mean left atrial (LA) voltage (1.72 +/- 0.73 vs 1.92 +/- 0.72 Hz, p = 0.045), and higher-frequency sites in the left atrium (71% vs 37%, p = 0.027). After a median follow-up period of 15 months, the single-procedure success rate (72% vs 53%, p = 0.008) and final success rate after multiple procedures (94% vs 81%, p = 0.02) were higher in the low hs-CRP group. In a multivariable regression model adjusted for other potential covariates, hs-CRP level (p = 0.021) and LA diameter (p = 0.032) were independent predictors of recurrence. In conclusion, baseline CRP levels before the first AF ablation procedure had an independent prognostic value in predicting long-term recurrence. Patients with a high hs-CRP level were associated with an abnormal LA substrate and high incidence of nonpulmonary vein AF sources., (Copyright 2010 Elsevier Inc. All rights reserved.)

Background: The objective of this retrospective cohort study was to compare the patent ductus arteriosus (PDA) closure rate with different routes (intravenous and enteral) of indomethacin treatment and neonatal outcomes., Methods: Infants with a birthweight < 1,000 g born between July 1997 and June 2007 at Taipei Veterans General Hospital and who received indomethacin treatment for PDA were included in the study. Outcome measures were ductal closure rate and neonatal outcomes., Results: Of 41 extremely-low-birth-weight infants with PDA, 3 infants had spontaneous closure and 3 died before treatment. Of the remaining 35 infants, 13 received enteral ethanol solution of indomethacin and 22 received the intravenous (IV) form. The total closure rates of the IV and enteral groups were 81.8% and 76.9%, respectively. There were no significant differences in the incidence of impaired renal function, necrotizing enterocolitis, chronic lung disease or severe retinopathy of prematurity between the 2 groups., Conclusion: Our results suggest that ethanol-based indomethacin is an effective alternative to IV indomethacin for the pharmacological closure of PDA in extremely-low-birth-weight infants.

Objective: The purpose of this study was to introduce a minimally invasive surgery using mosquito forceps for achieving the reduction of severely displaced supracondylar fracture of the humerus in children and evaluate the clinical outcome., Materials and Methods: Gartland type III supracondylar fractures of the humerus in children under the age of 12 were analysed from January 2000 to January 2007 at our institute. The control group cases were selected by successful reduction using the standard technique described by Rockwood and Wilkins (2001). The others composed the study group. This study included chart reviews, radiographic images of both the antero-posterior and the lateral views, physical examination, and Mayo elbow performance index scores preoperative, postoperative, and final follow-up., Results: Evaluations were completed for 42 cases. The mean age was 6.9 years and the group consisted of 23 boys and 19 girls. The mean follow-up time was 34.5 months. Twenty-six cases were of injuries to the left side, and 16 were of injuries to the right. The Mayo elbow performance index score was excellent in both groups. Operation time in the control and study groups was 46 and 79min, respectively. There was one case of iatrogenic ulnar nerve injury each in the study and control group. One case of loss of reduction and another with a combination of ulnar nerve injury and loss of reduction were noted in the control group. All four cases had an excellent final outcome. No mosquito-forceps-related complication was found, and in the final follow-up, no cubitus varus was found., Conclusion: Minimally invasive surgery with the assistance of mosquito forceps for the reduction of severely displaced supracondylar fracture of the humerus in children was shown to be a safe and effective alternative method. The final functional outcome was the same as that of the standard technique.

Background: Infants and children who undergo surgical repair of complex congenital heart diseases are prone to developing renal dysfunction. The purpose of this study was to investigate the risk factors associated with prolonged peritoneal dialysis (PD) and the mortality of pediatric patients with acute renal failure (ARF) after open heart surgery., Methods: From June 1999 to May 2007, a total of 542 children underwent open heart surgery for congenital heart disease. Fifteen (2.8%) experienced ARF and seven (1.3%) required PD. The clinical and laboratory variables were compared between the survivor and non-survivor groups of ARF patients that needed PD., Results: The non-survivors (n=3, 43%) had a Longer cardiopulmonary bypass time (154+/-21 vs. 111+/-8 minutes, p=0.012) and longer aorta clamping time (92+/-40 vs. 66+/-15 minutes, p=0.010) than the survivors (n=4, 57%). Before the PD, the pH and base excess of the arterial blood gas analysis in the survivors was much higher than that non-survivors (7.30+/-0.04 vs. 7.16+/-0.10, p=0.039; -5.15+/-3.13 vs. -12.07+/-2.9mmol/L, p=0.031). Furthermore, the survivors had a shorter interval between the onset of ARF and the day the PD was begun (1.2+/-0.4 vs. 4.3+/-1.2 days, p=0.001), and shorter duration of PD (6.6+/-2.7 vs. 13.0+/-3.5 days, p=0.036) than non-survivors., Conclusion: Early intervention with PD is a safe and effective method for managing patients with ARF after open heart surgery. The cardiopulmonary bypass and aortic clamping duration, time of initiating PD, duration of the PD, sepsis, and relative complications may predict the prognosis of these patients.

Gender differences of supraventricular tachycardias such as atrioventricular nodal re-entry, atrioventricular re-entry, and atrial fibrillation have been reported. There is little evidence of the effect of gender on focal atrial tachycardia (FAT). The study consisted of 298 patients who were referred to this institution for radiofrequency catheter ablation of FAT from October 1992 to April 2008 and included 156 men (52%) and 142 women (48%). Men were significantly older than women (57.9 +/- 18.2 vs 47.2 +/- 19.0 years old, p <0.001). Women had more associated arrhythmias (17.0% vs 28.9%, p = 0.01), mostly due to an increased incidence of atrioventricular nodal re-entrant tachycardia. Men had more cardiovascular co-morbidities (19.9% vs 9.9%, p = 0.02), a mechanism of increased automaticity (19.1% vs 8.1%, p = 0.01), and nonparoxysmal tachycardia (14.7% vs 4.4%, p = 0.01). No gender differences were noted among FAT number, left atrial involvement, shortest tachycardia cycle, success rate of catheter ablation, or recurrence rate of FAT. Mean duration of follow-up was 63.2 +/- 47.5 months. Premenopausal women had a lesser cardiovascular co-morbidity (15.3% vs 4.3%, p = 0.04) and a greater incidence of a mechanism of increased automaticity (13.4% vs 2.9%, p = 0.03). In conclusion, gender differences in electrophysiologic characteristics were noted in FAT.

Background: Information about the electrophysiologic characteristics and long-term outcome of catheter ablation in patients with multiple focal atrial tachycardia (AT) is limited., Objective: The purpose of this study was to investigate the electrophysiologic characteristics and long-term outcome of catheter ablation in patients with multiple focal AT., Methods: Two hundred fifty-one patients who were referred for radiofrequency catheter ablation of focal AT were included for analysis., Results: Forty-four patients who had focal AT with more than one focus were identified. Comparing focal AT with a single focus to that with more than one focus, the existence of a left atrial focus, cardiovascular comorbidity, nonparoxysmal tachycardia, shortest tachycardia cycle length, success rate of the ablation, and procedure time all differed. Multivariate logistic analysis revealed that a left atrial focus, cardiovascular comorbidity, and shortest tachycardia cycle length were independent predictors of focal AT with more than one focus. Noncontact mapping of the right atrium revealed larger low-voltage zone and longer total activation time for focal AT with more than one focus. Patients who had focal AT with more than one focus and a failed ablation had a greater number of focal ATs and mechanisms of nonparoxysmal tachycardia. Multivariate logistic analysis revealed that only the number of focal ATs predicted a failed ablation., Conclusion: Focal ATs with more than one focus have different electrophysiologic characteristics. This study provides new insight into the development and atrial remodeling of focal AT with multiple foci.

Chest pain is not an uncommon complaint among adolescents; however, it often leads them to seek emergency medical care. The variant angina (coronary artery spasm) with resulting acute myocardial ischemia is an extremely rare cause of chest pain among the pediatric population, and there are very few cases reported. We describe a 13-year-old boy with underlying intermittent Wolff-Parkinson-White syndrome and who had an acute coronary artery syndrome due to coronary artery vasospasm.

Background: Transcatheter closure of a secundum atrial septal defect (ASD) has become an effective method for surgical treatment. In this study, we evaluated the feasibility and accuracy of intracardiac echocardiography (ICE) for sizing ASDs compared with conventional methods., Methods: Between January 2004 and December 2006, 270 patients underwent transcatheter closure of secundum ASD by using septal occluders. For 142 patients, the procedure was guided by transesophageal echocardiography (TEE), and for 128 patients by ICE. We compared the maximal diameters of the ASDs obtained during angiocardiography, transthoracic echocardiography (TTE), ICE, and TEE with balloon-stretched sizes ascertained by using a sizing plate., Results: ASD diameters measured with the sizing plate were significantly correlated with those measured with ICE (r = 0.963), TEE (r = 0.912), angiography (r = 0.88), and TTE (r = 0.85). The predicted stretched diameter of the ASDs, i.e. (nonstretched diameter measured with ICE x 1.07) + 3.23 mm, agreed well with that measured by using a sizing plate (Ri = 0.974)., Conclusion: ASD diameters measured with ICE correlated with sizing-plate measurements better than those determined with TEE, angiography or TTE.

Background: Data detailing the age-related difference in the atrial substrate for formation of typical atrial flutter (AFL) are sparse., Objective: The purpose of this study was to characterize the difference in the right atrial substrate related to aging using noncontact mapping of the right atrium., Methods: A total of 54 patients (23 young [<60 years; 45 +/- 12 years] and 31 old [>or=60 years; 74 +/- 6 years]) with typical AFL who underwent three-dimensional noncontact mapping of typical AFL were enrolled in the study. The atrial substrate was characterized according to (1) regional wavefront activation mapping, (2) regional conduction velocity, and (3) regional voltage distribution by dynamic substrate mapping., Results: During activation mapping of the crista terminalis, two activation patterns were observed: (1) around the upper end of the crista terminalis (67%) and (2) through a gap in the crista terminalis. The presence of a crista terminalis gap was associated with a high incidence of induced atypical AFL/atrial fibrillation (P <.001). The conduction velocities of the medial cavotricuspid isthmus were slower in the old group than in the young group. In regional activation mapping of the AFL, the location of the slowest conduction shifted from the lateral cavotricuspid isthmus (71%) in the young group to the medial cavotricuspid isthmus (40%) in the old group. More cases with a low-voltage zone (

Background: In Taiwan, children with malignancies are treated under the protocols of the Taiwan Pediatric Oncology Group (TPOG). The purpose of this study was to determine the change in left ventricular (LV) function in pediatric patients undergoing chemotherapy., Methods: A total of 19 pediatric patients (mean age, 12.5 +/- 4.6 years; 11 males, 8 females) were enrolled. We divided the patients into 2 groups: (1) osteogenic sarcoma (OGS) group (n = 12; Group I); and (2) non-osteogenic sarcoma (non-OGS) group (n = 7; Group II). The accumulated dosages of anthracycline in Group I and II patients were 144.3 +/- 56.4 mg/M2 and 131.7 +/- 105.5 mg/M2 (p = 0.735), respectively. The children received echocardiography to investigate the parameters of LV systolic function, LV diastolic function, and myocardial performance index (MPI) after the entire chemotherapy course., Results: Higher E/A ratio (1.71 +/- 0.37), shorter isovolumic relaxation time (IRT, 42 +/- 19.14 ms), and shorter deceleration time (DT, 140.3 +/- 40.6 ms) were demonstrated in these patients. There was no statistically significant difference in the E/A ratio and DT between the 2 groups. Group I children were older (14.4 +/- 3.7 vs. 9.3 +/- 4.5 years; p = 0.015) and had lower MPI (0.20 +/- 0.02 vs. 0.28 +/- 0.07; p = 0.031) than Group II children., Conclusion: The children treated with chemotherapy using the TPOG protocol had a shorter IRT, higher E/A ratio and shorter DT. No significant evidence of anthracycline-related cardiotoxicity was found in any of the children in this study undergoing chemotherapy with the TPOG protocol.

Background: Hypoxic events and cardiac arrest may cause brain damage in critical infants. This study investigated cerebral tissue oxygenation and oxygen extraction in a piglet model of hypoxic events, cardiac arrest and effects of resuscitation., Methods: For the hypoxia experiment, anesthetized newborn piglets were randomized to a hypoxia group (n = 8) with decreasing ventilatory rate to 0, and a control group (n = 8) with no hypoxic conditions. Regional cerebral tissue oxygen saturation (rScO2, detected by near-infrared spectroscopy) and oxygen saturation were recorded every 5 minutes for 100 minutes. Fractional cerebral tissue oxygen extraction (FTOE) was calculated as (arterial oxygen saturation [SaO2] - rScO2)/SaO2. For the resuscitation experiment, animals were grouped as hypoxia-no CPR (n = 4), control-no CPR (n = 4), and control-CPR (n = 4) after cardiac arrest. Standard cardiopulmonary resuscitation (CPR) was performed on the control-CPR group and observed for 30 minutes., Results: Immediate and significant changes in rScO2, and gradual changes in FTOE were observed during the hypoxia experiment. In the resuscitation experiment, no significant differences in rScO2 were found between groups. However, the highest FTOE was observed in the control-CPR group., Conclusion: Noninvasive monitoring of rScO2 and evaluating FTOE changes during hypoxia and resuscitation may help clinicians evaluate brain tissue oxygenation and viability.

Background: Atrioventricular nodal reentry tachycardia (AVNRT) is based on the concept of dual AV node pathways that are functionally and anatomically distinct. The bigger coronary sinus ostium (CSO) in patients with AVNRT compared to other supraventricular tachycardias (SVTs) may produce separation of atrial inputs into the AV node or create anisotropic conduction, thus giving rise to a different AV nodal physiology. Previous studies measuring the size of the CSO using CS angiography between patients with AVNRT and other SVTs showed conflicting results. Besides, no previous studies have compared the CS morphology of the different forms of AVNRT., Objectives: This study compares the size and morphology of the CS among patients with typical AVNRT, atypical AVNRT and accessory pathways mediated reentrant tachycardia (AVRT)., Methods: Ninety-six patients with clinically documented SVTs were divided into three groups. The diameter of the CS was measured in LAO projection during end ventricular systole (by choosing the last ventricular inward motion). The CSO as well as 5, 10 and 15 mm inside the CS were measured. CS morphology is defined as either wind-sock shape or tubular shape., Results: The size of the CS ostium was 13.58 +/- 3.98, 15.93 +/- 4.86 and 12.50 +/- 2.83 mm for the atypical AVNRT, typical AVNRT and AVRT, respectively (p = 0.03). There was significant difference in the size of the CS from the ostium until 15 mm into the CS between 1) typical AVNRT and AVRT, 2) typical AVNRT and atypical AVNRT. Typical and atypical AVNRT patients had more windsock morphology CS (13/32, 40.6% and 10/32, 31.2%) compared to AVRT which had only one (1/32, 3.1%) windsock morphology (p = 0.002)., Conclusion: The easier CS cannulation in patients with typical AVNRT could be due to a bigger CS size and to a more windsock morphology. The CS size and morphology may be a very important substrate of tachycardia in patients with AVNRT.

Background: This study investigated the electrophysiologic characteristics, atrial activation pattern, and effects of radiofrequency (RF) catheter ablation guided by noncontact mapping system in patients with focal atrial tachycardia (AT)., Methods and Results: In 13 patients with 14 focal ATs, noncontact mapping system was used to map and guide ablation of AT. AT origins were in the crista terminalis (n=8), right atrial (RA) free wall (n=3), Koch triangle (n=1), anterior portion of RA-inferior vena cava junction (n=1), and superior portion of tricuspid annulus (n=1); breakout sites were in the crista terminalis (n=5), RA free wall (n=5), middle cavotricuspid isthmus (n=2), and RA-superior vena cava junction (n=2). ATs arose from the focal origins (11 ATs inside or at the border of low-voltage zone), with preferential conduction, breakout, and spread to the whole atrium. After applications of RF energy on the earliest activation site or the proximal portion of preferential conduction from AT origin, 13 ATs were eliminated without complication. During the follow-up period (8+/-5 months), 11 (91.7%) of the 12 patients with successful ablation were free of focal ATs., Conclusions: Focal AT originates from a small area and spreads out to the whole atrium through a preferential conduction. Application of RF energy guided by noncontact mapping system was effective and safe in eliminating focal AT.

Background: Obesity impairs performance in most athletic events. The prevalence of obesity in Taiwan has increased over the past decades. It is important to understand any alterations in cardiopulmonary responses to exercise in obese children. The purpose of this study is to evaluate the cardiorespiratory response to graded treadmill exercise testing protocol in obese children., Methods: Twenty obese and 10 control children between 8 to 12 years of age were recruited among patients at Pediatric Clinics. The treadmill was set at a grade of 10% to perform continuous treadmill walking. Measures of cardiopulmonary responses were recorded. Height, weight and body mass index were determined before testing., Results: Cardiopulmonary responses including heart rate (HR), systolic pressure (SP), rate-pressure product (RPP) and forced vital capacity (FVC) were significantly different between obese children and normal children during and after exercise. The correlations of cardiopulmonary function to age, sex, height, body weight, triceps and biceps skinfold thickness were assessed, and a significant correlation was found between HR and age (r = 0.5, p < 0.05), as well as biceps skinfold thickness (r = 0.5, p < 0.05). There was also a good correlation between predicted values of FVC and age (r = -0.5, p < 0.05). The HR (r = 0.79, p < 0.05) was in correlation with tricep skinfold thickness in normal healthy children., Conclusions: In conclusion, there appears to show a relatively less efficient cardiopulmonary response in obese children. Regular exercise that improves fitness and body composition should have a favorable effect on obese children.