mg molecular weight According to the evaluation of guideline
According to the evaluation of guidelines in syncope study 2 trial (EGSYS-2) score, syncope during effort was one predictor of cardiac syncope (OR, 17.0; 95% CI, 4.1–72.2) . In our study population, 27 of 119 patients (23%) in the non-arrhythmic T-LOC group suffered cardiac syncope, and there was no significant difference between the arrhythmic and non-arrhythmic syncope groups. Despite in-hospital testing and patient management, we were unable to diagnose the cause of the syncope in 11% of the study subjects. In the EGSYS-2 study, 2% of syncopal patients referred to the ED had an unknown cause of syncope;  in another study, the cause of syncope was unknown in 18% of patients referred to a syncope unit . The patients in the present study who required hospitalization for syncope of unknown cause might have been similar to those referred to the syncope unit.
Conflicts of interest
Introduction Catheter ablation procedures for arrhythmias such as supraventricular tachycardia and atrial flutter have become established with excellent results. The permanent cure of tachycardias using catheter ablation is possible. Pulmonary vein isolation (PVI) is a cornerstone of atrial fibrillation (AF) ablation [1–4]. Since its introduction, significant progress has been made in AF catheter ablation; left atrial (LA) linear ablation [5–8], complex fractionated atrial electrogram (CFAE) ablation  or defragmentation , non-pulmonary vein (non-PV) foci ablation , and cardiac ganglion plexus ablation [12,13] are effective adjunctive procedures of PVI for treating non-PV AF triggers and substrates. However, systematic indications for these adjunctive procedures have not yet been established, and their selection is at the discretion of the attending physician and institute. Reportedly, single-procedure AF ablation has an efficacy of 50–64% . Therefore, AF ablation procedures still have some obstacles to overcome. It has also been reported that mg molecular weight the incidence of complications associated with AF ablation, such as pulmonary vein stenosis, atrioesophageal fistula, gastric hypomotility, and phrenic nerve paralysis, differs from that associated with other catheter ablation procedures , and their incidence in Japan remains to be elucidated.
Materials and methods Continuous variables with a normal distribution were expressed as mean±SD, and the data were compared between the patient groups using an unpaired t-test. Variables that were not normally distributed were expressed as the median (lower quartile, upper quartile). The comparison of categorical variables was accomplished using Fisher\'s exact test. Analyses were conducted using the Stat View 5.0 software (SAS Institute; NC, USA).
Results A total of 199 institutes voluntarily submitted data and 165 (83%) of those had an electrophysiological center capable of catheter ablation in September, 2011; the majority (n=128, 64%) performed AF ablation during that period. A total of 932 sessions were performed, with a median of 5 AF procedures (lower and upper quartiles 2 and 9) per center per month. The largest center performed 56 AF ablation procedures in the month. Table 1 shows the patients\' background data. The average age was 62.1±10.4 years, and 76.8% were male. Of all sessions, 77.5% were first AF ablation sessions, 19.7% were second sessions, and 2.8% were subsequent sessions. Patients with paroxysmal AF constituted 65.7% of the patients; 89.6% of those suffered from AF attacks more than once per week. The average CHADS2 and CHA2DS2-VASc scores were 1.0±1.0 and 1.5±1.3, respectively. Patients with AF alone were a minority (22.3%); 51.8% patients had a history of hypertension. The average left ventricular ejection fraction and LA volume (dimension) were 63.5±9.5% and 70.4±33.8mL (40.7±15.2mm), respectively. The average number of antiarrhythmic drugs used was 1.2±0.9, and the 3 most common drugs were pilsicainide (27.3%), bepridil (23.4%), and cibenzoline (18.5%). However, 189 patients (20.2%) had no history of antiarrhythmic drug use.