Background—: Catheter ablation of para-Hisian accessory pathways (APs) can be challenging because of adjacent conduction tissue. Some different approaches for ablation, including the inferior vena cava approach (IVC-A), the noncoronary cusp approach (NCC-A), or the superior vena cava approach (SVC-A), have been reported. However, when should para-Hisian APs be mapped and ablated by the IVC-A, NCC-A, or SVC-A is not well established. Methods and Results—: This study included 55 consecutive patients (mean age, 53±11 years, 36 males) with para-Hisian APs. On the basis of the approach resulting in successful ablation, patients were divided into IVC-A, NCC-A, and SVC-A groups. The clinical characteristics, surface ECG, intracardiac electrogram findings, and response to ablation were analyzed. Para-Hisian APs were eliminated by IVC-A in 48 of the 55 (87%) patients. The rates of para-Hisian APs requiring NCC-A (4/55 patients, 7%) and SVC-A (3/55 patients, 6%) were relatively low. During mapping at the para-Hisian region, the local ventricular and atrial potentials were well fused during retrograde AP conduction in 45 of the 48 patients in IVC-A group, 0 of the 4 patients in NCC-A group, and 1 of the 3 patients in SVC-A group, respectively. There was no significant difference in the preexcitation characteristics among the 3 groups. Conclusion—: Most para-Hisian APs can be safely and effectively ablated by IVC-A, and ablation in the NCC is not an initial or a preferred approach. The degree of local ventriculoatrial fusion in the para-Hisian region during retrograde AP conduction can differentiate or predict the successful ablation site.

Distinguishing between ventricular arrhythmias originating from the left ventricular infero-septal papillary muscles (PM) and those from the left posterior fascicle (LPF) by surface electrocardiography (ECG) is very difficult. This study aimed to report the ECG characteristics and radiofrequency catheter ablation of PM and LPF ventricular arrhythmias. A total of 127 patients underwent catheter ablation of idiopathic ventricular arrhythmias originating from the LPF (n = 106; 85 males; 10–70 years) or PM (n = 21; 14 males; 4–68 years) were studied. A three-dimensional electroanatomic system (3D-EAS) was used to aid ablation. PM ventricular arrhythmias had a longer QRS duration (154.4 ± 18.0 vs. 119.7 ± 12.6 ms, P < 0.001) than LPF ventricular arrhythmias. All 7 ventricular arrhythmias with QRS duration >160 ms originated from the PM, whereas all 87 ventricular arrhythmias with QRS duration 0.85 arose from the LPF. Of the 8 PM ventricular arrhythmias patients whose initial ablation was undertaken using a non-irrigated 4 mm-tip catheter, 1 failed and 6 recurred. However, of the remaining 13 ones using an irrigated catheter and the 3D-EAS, all succeeded and 2 recurred. No complications were noted in any patient. PM ventricular arrhythmias could be identified from LPF ventricular arrhythmias by calculation of QRS duration combined with V_i/V_t using ECG.

Background and objective: This study aimed to assess the efficacy and safety of “one-stop” procedures that combined radiofrequency catheter ablation and left atrial appendage closure (LAAC) with the Watchman device under the guidance of intracardiac echocardiography (ICE) vs. transesophageal echocardiography (TEE) in patients with atrial fibrillation.Methods and results: In this study, we prospectively enrolled patients who underwent “one-stop” procedures under the guidance of ICE (n = 193, 109 men, 65.02 ± 8.47 years) or TEE (n = 109, 69 men, 64.23 ± 7.75 years) between January 2021 and October 2022. Intraprocedural thrombus formation in the left atrial appendage (LAA) was observed in 3 (1.46%) patients in the ICE group and 15 (11.63%) patients in the TEE group (P < 0.05) before LAAC. Total fluoroscopy time and dose in the ICE group were less than those in the TEE group. The total “one-stop” turnaround time and LAAC procedure time in the ICE group were significantly shorter than those in the TEE group (P < 0.05). Postoperative esophagus discomfort, nausea and vomiting, and hypotension were more often seen in the TEE group (P < 0.001). There was no significant difference in matched cases between ICE and fluoroscopy measurements (P = 0.082). The TEE results related to LAAC and clinical events were similar between the two groups during the follow-up (P > 0.05).Conclusion: The ICE-guided “one-stop” procedure was safe and feasible with less radiation exposure, shorter turnaround time, and fewer complications and intraoperative thrombus formations than the TEE group. ICE offered accurate measurements in the LAA dimension during LAAC. Echocardiography during the “one-stop” procedures was necessary to rule out the intraoperative thrombus.

Introduction. Purkinje system and false tendons (FTs) are related to ventricular arrhythmia, but the association between Purkinje fibers and FTs is not clear. This study investigated the associations of anatomical and electrophysiological characteristics between Purkinje fibers and FTs. Methods and Results. We optimized the protocol of Lugol’s iodine solution staining of Purkinje fibers to study the anatomical structure and originated a novel electrophysiological mapping method, named the direct visual mapping (DVM) method, to study the electrophysiological characteristics. By using the above-mentioned innovations in 12 dogs, we found the following. (1) There was no Purkinje fiber found 0.5 cm–1.0 cm below the valve annulus or on the leaflets or chordae tendineae of the mitral valve or adjacent to the top 1/3 of the papillary muscle. (2) Purkinje fibers existed in all FTs, including smaller and tiny FTs. (3) The Purkinje fibers contained in the FTs extended from the proximal to the distal end, and their electrophysiological characteristics were similar to the fibers on the endocardium, including anterograde, retrograde, and decremental conduction and automaticity. Conclusions. Purkinje fibers are commonly found in FTs. The electrophysiological characteristics of the Purkinje fibers contained in FTs are similar to the fibers on the endocardium. FTs might have an anatomical and electrophysiological basis for ventricular arrhythmia.