Utility of local atrial electrogram pattern for predicting left main coronary artery anatomical distance during mapping in the left pulmonary sinus of valsalva.

BACKGROUND: Ablation of right ventricular outflow tract (RVOT) ventricular arrhythmia (VA) within the left pulmonary sinus of Valsalva (LPSV) may increase the risk of left main coronary artery (LMCA) injury. PURPOSE: To delineate the anatomical characteristics between LMCA and LPSV and their association with atrial potential (AP) mapping in LPSV. METHODS: A total of 104 consecutive patients with RVOT-VA undergoing cardiac-gated computed tomography coronary angiography (CTCA) after ablation were retrospectively analyzed. RESULTS: The LMCA-LPSV anatomic relationship was classified into three types based on the CTCA measurements. Types 1 and 2 had a shorter LMCA-LPSV distance than that of type 3 (P < .001). The left atrial appendage (LAA)-LMCA distance and LAA-LPSV distance were associated with the incidence of AP in LPSV (odds ratio [OR] = 3.43, 95% confidence interval [CI]: 1.86-6.34, P < .001; OR = 1.196, 95% CI: 1.09-1.31, P < .001, respectively). Furthermore, the LMCA-LPSV distance showed a linear correlation with the LAA-LPSV distance (r2 = 0.93, P < .001). According to receiver operating characteristic (ROC) analysis, a LMCA-LPSV distance <5.4 mm could predict the possibility of AP during LPSV mapping (sensitivity 83%, specificity 81%, and area under the ROC curve 0.86). CONCLUSIONS: The presence of AP in the LPSV may be useful to predict a short distance from the LPSV to the LMCA and to identify patients at higher risk of LMCA injury. This information may contribute to efficient and safe ablation in this area but should be confirmed in future studies.

Image integration into 3-dimensional-electro-anatomical mapping system facilitates safe ablation of ventricular arrhythmias originating from the aortic root and its vicinity.

Aims: During ablation in the vicinity of the coronary arteries establishing a safe distance from the catheter tip to the relevant vessels is mandatory and usually assessed by fluoroscopy alone. The aim of the study was to investigate the feasibility of an image integration module (IIM) for continuous monitoring of the distance of the ablation catheter tip to the main coronary arteries during ablation of ventricular arrhythmias (VA) originating in the sinus of valsalva (SOV) and the left ventricular summit part of which can be reached via the great cardiac vein (GCV). Methods and results: Of 129 patients undergoing mapping for outflow tract arrhythmias from June 2014 till October 2015, a total of 39 patients (52.4 ± 18.1 years, 17 female) had a source of origin in the SOV or the left ventricular summit. Radiofrequency (RF) ablation was performed when a distance of at least 5 mm could be demonstrated with IIM. A safe distance in at least one angiographic plane could be demonstrated in all patients with a source of origin in the SOV, whereas this was not possible in 50% of patients with earliest activation in the summit area. However, using the IIM a safe position at an adjacent site within the GCV could be obtained in three of these cases and successful RF ablation performed safely without any complications. Ablation was successful in 100% of patients with an origin in the SOV, whereas VAs originating from the left ventricular summit could be abolished completely in only 60% of cases. Conclusion: Image integration combining electroanatomical mapping and fluoroscopy allows assessment of the safety of a potential ablation site by continuous real-time monitoring of the spatial relations of the catheter tip to the coronary vessels prior to RF application. It aids ablation in anatomically complex regions like the SOV or the ventricular summit providing biplane angiograms merged into the three-dimensional electroanatomical map.

Vagal reflex provoked by radiofrequency catheter ablation in the right aortic sinus cusp: a Bezold-Jarisch-like phenomenon.

A 66-year-old woman with idiopathic premature ventricular contractions with a left bundle branch block QRS morphology and left inferior axis underwent electrophysiologic testing. Successful radiofrequency ablation was achieved in the right coronary cusp (RCC). However, radiofrequency ablation at sites adjacent to the successful ablation site provoked sinus bradycardia followed by atrioventricular conduction block. That phenomenon might be explained by a vagal reflex through stimulation of vagal pathways or receptors in the anterior epicardial fat pads neighboring to the RCC. A vagal reflex should be kept in mind as a complication during catheter ablation of ventricular arrhythmias originating from the RCC.