Left Atrial Reverse Remodeling Following the Modified Box Isolation with Centerline in Patients with Persistent Atrial Fibrillation.

Esophageal injury is a rare but serious complication of atrial fibrillation (AF) ablation. To minimize esophageal injury, our persistent AF (PerAF) protocol involves complete left atrial posterior wall (LAPW) and pulmonary vein (PV) isolation (box isolation), with a centerline away from the esophagus. However, there has been a concern that extensive LA isolation might deteriorate LA function. There has been a paucity of data on LA remodeling after box isolation. Therefore, we compared LA size pre- and post-box isolation with an LAPW centerline in patients with PerAF.Patients who underwent catheter ablation (CA) for PerAF between November 2016 and December 2018 were retrospectively evaluated.The LAPW, including all PVs, was completely isolated in 105 consecutive patients (75 men; mean age: 68 ± 10 years) with PerAF, including 58 patients with long-standing PerAF. During a follow-up of 660 ± 332 days, 76 patients (72%) were arrhythmia-free. The LA dimension (38 ± 6 mm versus 42 ± 7 mm; P < 0.0001) and volume index (38 ± 13 mL/m2 versus 47 ± 14 mL/m2; P < 0.0001) at 6 months post-ablation were significantly decreased in patients who maintained sinus rhythm compared to pre-ablation. In patients with recurrent AF/atrial tachycardia (AT), these parameters were also significantly decreased (P < 0.001, respectively).Box isolation with a posterior centerline has no esophageal complications and a high clinical success rate in patients with PerAF. Reverse remodeling could be achieved even when using extensive isolation of the PV and LAPW in patients with PerAF.

Idiopathic Ventricular Arrhythmia Ablation Using Non-Fluoroscopic Catheter Visualization System.

A novel, sensor-based, electromagnetic, non-fluoroscopic catheter visualization (NFCV) system shows tracked catheters directly on pre-acquired fluoroscopy or cine loops. We aimed to evaluate the effectiveness of this system in the setting of catheter ablation for idiopathic premature ventricular contractions/ventricular tachycardia (i-PVC/VT).A total of 30 i-PVC/VT ablation procedures were performed using the NFCV system in conjunction with three-dimensional electroanatomic mapping system (3D-EMS) between January 2013 and April 2017. At the beginning of the procedure, cine loops of right and left anterior oblique views were obtained and replayed for subsequent mapping and ablation. Right ventriculography, aortography, or coronary angiography was performed, depending on the chamber of interest. We reviewed procedural parameters, comparing with the i-PVC/VT ablation procedure using conventional fluoroscopy (CvF) system (pre-, and post-NFCV implementation; 20 and 11 cases, respectively).I-PVC/VTs were successfully eliminated in 26 patients (87%) in the NFCV group and in 26 (84%) in the CvF group (P = 1.000). The procedure time in the NFCV group was comparable to that in the CvF group (119.8 versus 125.0 minutes, respectively, P = 0.868); the total fluoroscopy time was significantly shorter in the NFCV group (3.3 versus 16.6 minutes, P < 0.001). One patient in the CvF group experienced cardiac tamponade, requiring pericardial drainage. No major complications were encountered in the NFCV group.NFCV system, in conjunction with 3D-EMS, was safe and feasible for i-PVC/VT mapping and ablation. The system contributed to dramatically reduced fluoroscopy time, compared with CvF.

Reducing radiation exposure during atrial fibrillation ablation using lectures to promote awareness.

Objective: Recently, concern has increased regarding the hazards of radiation exposure in patients and laboratory staff. Since the numbers of complex catheter ablations (CA) performed, duration of procedure times, and need for multiple sessions have increased, radiation exposure during each session needs to be minimised. Our study aimed to assess the impact of awareness on radiation exposure during CA for atrial fibrillation (AF). Methods: Mini-course lectures was delivered to the physicians and staff in the electrophysiology division. Its effect on the fluoroscopic time and radiation dose during AF ablation before (Group I, n=70), shortly after (Group II: n=70) and remotely after the mini-lecture (Group III, n=70) were evaluated. Patient demographics, preoperative testing and procedural parameters were collected. Results: The fluoroscopic time significantly reduced after the lecture (Group I and II: 25.1±10.0 and 15.1±7.3 min, respectively (p<0.0001)), and remained so in Group III (13.0±5.4 min), despite the increase in the number of persistent AFs. The radiation dose also significantly reduced (Groups I, II, III: 295.0±263.0, 109.6±103.5 and 110.1±89.6 mGy, respectively (p<0.0001)). Conclusion: Awareness on radiation exposure led to a significant reduction in fluoroscopic time and radiation dose during CA for AF, the effect of which persisted even to remote periods following the procedure.

Elongated ascending aorta predicts a short distance between his-bundle potential recording site and coronary sinus ostium.

BACKGROUND: When performing catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT), it can be difficult to maintain a safe distance from the His recording site to avoid AV block in patients with a short distance between this recording site to the coronary sinus (CS) ostium (small triangle of Koch [TOK]). In this study, we sought to identify parameters predicting small TOK and test these parameters in patients undergoing AVNRT catheter ablation. METHODS: Twenty-eight patients who underwent catheter ablation of atrial fibrillation using a three-dimensional (3D) electroanatomical mapping system (EAM) with computed tomography (CT) merge (23 males; mean age, 65.8±12.1 years) were included. The shortest distance between the CS ostium and His recording sites (His-CSd) was measured on the EAM. Aortic (Ao) unfolding in chest X-ray scan, Ao angle to the LV, Ao length, Ao to the right ventricular distance, size of the Valsalva in the CT scan, and parameters of echocardiogram were evaluated. The identified parameters were subsequently tested as predictors for small TOK in patients undergoing AVNRT ablation. RESULTS: The size of TOK was associated with Ao length (r = -0.70, p<0.01), left ventricular end-systolic dimension (LVDs) (r = -0.51, p<0.01), and Ao unfolding. In patients with AVNRT, only Ao unfolding predicted a smaller TOK. CONCLUSIONS: Small TOK was associated with longer Ao, larger LVDs, and Ao unfolding. Of these, Ao unfolding was associated with smaller TOK in patients with AVNRT.