Nonpharmacological therapy is being evaluated for the prevention of atrial fibrillation (AF). Pacing has been proposed as a one of the option to prevent AF. In patients with bradycardia and requiring pacemaker, physiological pacing such as dual chamber pacing or atrial pacing has an advantage against ventricular pacing in prevention AF. Pacing from novel site like the dual-site atrium, biatrial, Bachman, and low sepatl pacing may reduce AF burden and new anti-AF pacemakers with atrial prevention algorithm may decrease AF further. However, selecting the appropriate patients and adopting tailored-therapy for individual patient is likely to remain one of the difficulties in achieving an advantage. This review discusses the current status of pacing therapy for the prevention of AF. It also discusses the some of merits and limitations of pacing therapy for the treatment of AF.

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Ventricular fibrillation (VF) in out-of-hospital cardiac arrest (OHCA) is a main target for resuscitation.
Methods and results: We analyzed Utstein-style data in Sendai City (population 1,020,000), Japan from January 2002 to March 2004. The incidence of OHCA overall was 62.3/100,000/year. The incidence of the bystander-witnessed VF was 2.5/100,000/year. In younger patients (20–65 years of age), the percentage of VF was 52% when cardiac origin was presumed by bystander witness, and ECG was recorded within 10 minutes from the collapse. In older patients (over 65 years of age), however, the percentage of VF was 21% when they were bystander-witnessed, and ECG was recorded within 10 minutes from the collapse. No VF was reported when the ECG was recorded more than 15 minutes after the collapse. The thirty-day survival rate was 21% in the bystander-witnessed VF cases with cardiac etiology, but 0% in the non-VF cases. The bystander CPR was significantly associated with improved 30-day survival rate. Conclusion: Younger age, male gender, and shorter collapse-to-ECG time are significantly associated with the appearance of VF in bystander-witnessed OHCA with cardiac etiology. Bystander CPR was significantly associated with the improvement in prognosis of those VF patients.

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Introduction: Due to the difficulty in performing detailed mapping around the tricuspid annulus and the high occurrence of mechanical trauma during the procedure, the outcome of right-sided accessory pathway (AP) ablation still has a relatively high primary failure and recurrence rate.
Methods and Results: Six patients with right free-wall APs underwent electroanatomical mapping. The AP had retrograde unidirectional conduction in 3 patients, anterograde unidirectional conduction in 1 patient, and bidirectional conduction in 2 patients. The right atrial (RA) activation map was constructed during right ventricular (RV) pacing (n=5), and the RV activation map was constructed during RA pacing (n=3). During mapping, the AP conduction was interrupted by catheter mechanical trauma in 3 patients. The first RF application successfully eliminated the AP conduction within 2 seconds in 3 patients with concealed pathways. In the remaining 3 patients, rescue RF energy was delivered at the tagged bump site on the map. The mean procedure time was 214±77 minutes, and mean fluoroscopy time 63±23 minutes. No recurrence occurred during 12±3.2 months of follow-up in any of the patients.
Conclusions: With the guidance of an electroanatomical mapping system, right-sided accessory pathways can be satisfactorily eliminated without later recurrence.

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We examined a patient with concealed WPW syndrome who exhibited five different electrocardiographic waveforms during tachycardia.
With the intracardiac electrogram, all tachycardia were artrioventricular reciprocating tachycardia with retrograde conduction through only the accessory pathway where each artrioventricular conduction form varied: i.e., one with anterograde conduction through the fast pathway, one with anterograde conduction through the slow pathway, one with anterograde conduction through the fast pathway and slow pathway alternately, and an irregular R–R interval, one with anterograde conduction through the fast pathway and wide QRS tachycardia with the right bundle branch block type, and one with anterograde conduction through the fast pathway and wide QRS tachycardia with left bundle branch block.
His bundle electrogram might be split and H, H′ was recorded at the time of sinus rhythm. Furthermore, the right and left bundle branches exhibited a different refractory period because of longitudinal dissociation in the His bundle. Therefore wide QRS tachycardia with both right and left bundle branch block might appear without complete atrioventricular block.
In addition to the association between fast pathway and slow pathway, right and left bundle branch block patterns appeared.

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This case report describes the treatment of atrial fibrillation (AF) in a patient with Brugada syndrome. We found the triggers of AF in the superior vena cava during electrophysiological study and the isolation of superior vena cava with catheter ablation successfully eliminated the recurrence of AF. This case suggests that abnormal myocardial repolarization due to Na⁺-channel abnormality is not always the etiology of AF in patients with Brugada syndrome. In case of the focal trigger related to the initiation of AF, catheter ablation can be an effective therapeutic strategy.

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Given concerns regarding electrode fixation and risk of dislodgement, transvenous implantation of a tined endocardial electrode into the right atrium is considered difficult in patients who require permanent atrial pacing following cardiac surgery. Implantation of a tined endocardial electrode into the right atrium was performed intraoperatively for 3 patients who required implantation of a permanent atrial electrode during the cardiac operation. This technique yielded excellent results during the mean follow-up period of 65 months, with low stimulation thresholds (mean 2.85 μJ), sufficiently high sensing thresholds (mean 2.23 mV) and stable lead impedances (mean 491.7 ohm). This technique offers a useful and secure method for patients with preoperative bradycardial arrhythmias who require implantation of a permanent atrial electrode during open-heart surgery.

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The cephalic vein is recommended as the access route for an implantable cardioverter defibrillator lead to avoid complications associated with subclavian vein puncture; however, cephalic vein cutdown is not necessarily preferred, mainly because of procedural complexity. To facilitate cephalic vein cutdown, we have devised the following method. An 8 Fr catheter is placed in the cephalic vein over a guidewire inserted percutaneously from the left peripheral cephalic vein. The catheter, which is palpable beneath the skin prior to incision, indicates the location of the cephalic vein, facilitating its isolation. A specially designed 9 Fr tear-away sheath-dilator unit is used to place leads. With its long-tapered and curved tip, the unit is easy to insert, even when the cephalic vein is stenotic or tortuous. The 30-cm-long sheath reaches the right atrium, and thus the lead is advanced directly to the right atrium without risk of vascular injury. This technique may be feasible in the majority of patients and can even be used by inexperienced implanters.

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