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Purpose: Non-pulmonary vein (PV) foci are sometimes difficult to identify and eliminate. This study aimed to characterize non-PV foci using the EnSite array or NavX system. Methods and Results: 138 patients with atrial fibrillation (AF) were included. All patients underwent PV isolation and additional ablation of non-PV foci if present. We revealed 17 non-PV foci in 15 patients. Nine foci induced AF and 8 foci showed more than 3 beats firing. Eight foci occurred spontaneously and the others were induced by low dose of isoproterenol (0.5γ, n=1) or high dose (≥10γ, n=8). The non-PV foci were distributed in the SVC (n=9, 50%), left atrium (LA) (n=5, 29%; 2 anterior wall, interatrial septum, appendage and mitral annulus), right atrium (RA) (n=3, 18%; lateral, posterolateral, anterolateral). 2nd session ablation was required in 36 patients (26%) and 31 patients had LA-PV reconnection. We revealed 16 non-PV foci in 14 patients in the 2nd session. Only one patient had non-PV foci recurrence from SVC. The others were firing at the different site from 1st session. Conclusion: The site of Non-PV foci was half in the SVC and each quarter in the LA and RA. The distribution of LA foci was various while RA foci existed near lateral side. If non-PV foci were successfully terminated, other foci may cause the recurrence of atrial fibrillation.

AF termination was often occurred during ganglionated plexi (GP) ablation. The purpose of this study was to characterize the electrograms at the site of AF termination by GP ablation. Method: Eighteen patients with AF termination by GP ablation were studied. In case of patients with sinus rhythm, AF was induced by rapid atrial pacing. The sites where vagal response was evoked by high-frequency stimulation were determined as GP sites and ablated. The bipolar electrograms were recorded in a 4.5-s window before the RF delivery. Result: AF termination was seen at superior left GP ablation in 3 patients, anterior right in 2 patients, inferior left in 6 patients, and inferior right (in 7 patients). Continuous electrical activity (CEA) was seen at the termination site in 16 (89%) patients. Other 2 patients without CEA, cycle length was 207±18 ms. The maximum duration of CEA was 1.8±0.3 of 4.5 sec. There were 2 patients with only CEA at the termination sites during all recording period. The maximum amplitude of CEA in 16 patients was 0.58±0.99 mV. Conclusion: The electrograms at the sites of AF termination by GP ablation show mainly transient CEA with relatively low voltage.

The Ganglionated Plexi (GP) and complex fractionated atrial electrograms (CFAE) play the important role as the perpetuator of atrial fibrillation (AF). GP ablation is known as alternative procedure for AF. The aim of this study was to evaluate the contrast between the area of the GP and CFAE. Method: Ten consecutive patients with AF were studied. For patients with sinus rhythm, AF was induced by rapid atrial pacing. The geometry of Left atrium (LA) was reconstructed with electroanatomical mapping system (CARTO XP). Bipolar electrograms recorded during 2.5 second were analyzed using CFAE software module. The algorism was customized to demonstrate the classification as follows in Interval confidence level (ICL) map. Sites with continuous or transient fractionated atrial potentials were colored red. Sites with irregular amplitude, polarity, cycle length but not rapid were colored green. Sites with slow organized atrial potential were purple. The sites where vagal response was evoked by high-frequency stimulation were identified as GP sites and marked on the geometry. Result: A total of 1,107 points were taken in LA. Among a total of 197 GP points, 139 (77.2%) points were in colored red and categorized as in CFAE area. GP points in colored purple categorized as in slow organized area were only 4 points (2.3%). Conclusion: The Ganglionated Plexi is strongly related to CFAE.

The antifibrillatory effect of ganglionated plexi (GP) ablation is not well established. The aim of this study was to evaluate the factors associated with termination during GP ablation in patient with paroxysmal AF. Methods: Thirty-two consecutive paroxysmal AF patients (age 61±10 years, 25 male) who underwent the selective GP ablation guided by high frequency stimulation (HFS) were enrolled in this study. The five major left atrial GP were localized by delivering HFS (20 Hz, 20 V, 10 ms pulse width). Radiofrequency current is then applied to that site to eliminate the parasympathetic response. We ablated GP first, and antrum PV electrical isolation (APVI) adjunctively. We measured cycle length (CL) in each PV, left atrial appendage (LAA), coronary sinus (CS), RA, during AF before any ablation. We investigated the termination of AF in relation with GP ablation. Results: AF was induced and sustained in 29 patients. AF terminated during GP ablation in 14 patients (48%), during APVI in 6 patients (21%). Two of 3 patients without sustained AF had SVC foci. The LAA and CS AFCL (142±22 ms, 138±19 ms) in 9 patients without termination were shorter than that in 20 patients with termination (170±33 ms, 171±27 ms, p

Background Noncontact mapping is useful for the diagnosis of various arrhythmias. Virtual unipolar electrogram morphologies (VUEM) of the conduction block and the turnaround points, however, are not well defined. We compared the VUEM characteristics of a transverse conduction block in the posterior right atrium (RA) with those of contact bipolar electrograms obtained during typical atrial flutter (AFL). Methods Contact bipolar electrograms were used to map the posterior RA during typical AFL in 16 patients. Twenty points of the VUEM recorded along the block line were analyzed and compared with contact bipolar electrograms. Results Seventeen AFLs were analyzed. Fifteen AFLs showed an incomplete transverse conduction block in the posterior RA by contact bipolar mapping. A double potential on the block line corresponded to the two components of the VUEM, in which the second component showed an Rs, RS, or rS pattern. At the turnaround point, a fused double potential of the contact bipolar electrograms corresponded to a change of the second component of the VUEM from an rS to a QS morphology. Two AFLs showed a complete block line in the posterior RA. The contact bipolar electrogram showed double potentials from the inferior vena cava to the superior vena cava, whereas the second component of the VUEM remained in an unchanged Rs, RS, or rS pattern. Conclusion VUEM analysis was a reliable method for identifying the posterior block line during AFL. This method may also be applicable for detecting block lines and turnaround points of circuits in other unmappable arrhythmias.

Purpose Dabigatran is effective for both the prevention of stroke and bleeding in patients with atrial fibrillation (AF). However, the safety and efficacy of the use of dabigatran in the peri-procedural period for radiofrequency catheter ablation (RFCA) of AF is unknown. Therefore, the purpose of this study was to evaluate the safety and efficacy of dabigatran in the peri-procedural period for RFCA of AF and the duration of hospital stay. Methods Consecutive patients (n = 227) who underwent RFCA for AF were prospectively analyzed. Peri-procedural anticoagulant therapy with dabigatran (n = 101, D group) was compared with warfarin and heparin bridging (n = 126, W group). Dabigatran was discontinued 12–24 h before and restarted 3 h after the procedure. Warfarin was stopped 3 days before the procedure and unfractionated heparin was administered. Results Ischemic stroke occurred in one patient of the D group (0.8 %). There was no significant difference between the two groups in the incidence of major bleeding (three cases of cardiac tamponade in each group and one case of intracranial bleeding in the W group, p = 0.93) or minor bleeding (five cases in the D group vs. five in the W group, p = 0.54). The duration of hospital stay was significantly shorter in the D group than in the W group (7.2 vs. 10.3 days, p = 0.0001). Conclusions Peri-procedural anticoagulation therapy with dabigatran for RFCA of AF was equally safe and effective compared with warfarin and heparin bridging. The use of dabigatran for RFCA of AF shortened the duration of hospital stay.