Targeting the ectopy‐triggering ganglionated plexuses without pulmonary vein isolation prevents atrial fibrillation

Figures

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  Figure 1. An example of mapping for an ET‐GP site using synchronized HFS is shown on the left‐hand side. PA view of the left atrium at the bottom shows that the ablation catheter (Map) was positioned in the RIPV roof. The pulmonary vein catheter (Lasso) was inserted into the RSPV. Pacing was performed first, followed by delivery of HFS coupled to each pacing stimulus (synchronized HFS). After the third HFS train, PV ectopy was initiated (earliest PV 13–14) which triggered AF. This site was marked as an “ET‐GP” site, tagged green in the CARTO™ geometry. After performing ablation at this site, retesting with synchronized HFS could not trigger the same response as before ablation. This confirmed adequate ablation at this site. We mapped and ablated the rest of the ET‐GPs this way. Purple tags on CARTO represented negative responses to HFS. ET‐GP, ectopy‐triggering ganglionated plexus, HFS, high‐frequency stimulation; PA, posterior–anterior; PV, pulmonary vein; RIPV, right inferior pulmonary vein; RSPV, right superior pulmonary vein

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  Figure 2. Mapping for AVD‐GP and testing after ablation. During AF, continuous HFS was performed to identify AVD‐GPs as in the top panel. Here, we paced five times to ensure that there was no ventricular capture. A continuous train of HFS was then delivered at the distal poles of an ablation catheter (Mapd). A significant AV dissociation occurred, causing asystole of 3.6 s. We stopped HFS at this point and there was a rapid RR interval recovery and continuation of AF. This site was determined as an AVD‐GP site and ablated at the end of the procedure. The bottom panel shows that retesting with continuous HFS at this ablated site did not trigger any AV dissociation again. This confirmed adequate ablation at this site. We mapped and ablated the rest of AVD‐GPs this way. AVD‐GP, atrioventricular dissociating ganglionated plexus; BP, blood pressure; HFS, high‐frequency stimulation

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  Figure 3. Study flowchart. We recruited 67 patients, of which 8 initially randomized to ET‐GP were crossed over to the PVI group due to sustained AF precluding completion of ET‐GP mapping protocol. After changing our protocol to allow completion of GP mapping in AF, we randomized patients 2:1 for GP ablation until more equal distribution of patients into each group. The final number of patients receiving PVI and GP ablation were 36 and 31, respectively. Five patients from the GP ablation group had a combination of ET‐GP and AVD‐GP ablation. AF, atrial fibrillation; AVD‐GP, atrioventricular‐dissociating ganglionated plexus; ET‐GP, ectopy‐triggering ganglionated plexus; GP, ganglionated plexus; PVI, pulmonary vein isolation

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  Figure 4. Average RF energy used in PVI and GP ablation. (A) A comparison of the average RF energy used between patients having PVI and GPA. The average RF energy used in PVI and GPA were 55.7 ± 22.3 and 23.3 ± 14.4 kWs, respectively (p ≤ .0001). (B) A comparison of the average RF energy used between patients having PVI and GPA who did not reach primary end‐point. The average RF energy used in successful PVI and GPA were 54.2 ± 17.7 and 24.6 ± 15.3 kWs, respectively (p ≤ .0001). GPA, ganglionated plexus ablation; PVI, pulmonary vein isolation; RF, radiofrequency

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  Figure 5. Example of a patient who had ET‐GP ablation and free from AF/AT at 12‐month follow‐up. Different projections of the left atrial CARTO™ 3D map are shown. Six ET‐GPs were identified and ablated. This was a 53‐year‐old male with hypertension, normal left ventricular systolic function, and normal left atrial size. AP, anterior–posterior; ET‐GP, ectopy‐triggering ganglionated plexus; HFS, high‐frequency stimulation; INF, inferior; LAO, left anterior oblique; LIPV, left inferior pulmonary vein; LSPV, left superior pulmonary vein; PA, posterior‐anterior; RAO, right anterior oblique; RF, radiofrequency; RIPV, right inferior pulmonary vein; RSPV, right superior pulmonary vein; SUP, superior

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  Figure 6. Example of a patient who had both ET‐GP and AVD‐GP ablated and free from AF/AT at 12‐month follow‐up. Different projections of the left atrial CARTO™ 3D map are shown. In total, 11 ET‐GPs and 12 AVD‐GPs were identified and ablated. This was a 63‐year‐old male with hypertension, diabetes mellitus, previous percutaneous coronary intervention to the right coronary artery, normal left ventricular systolic function, and mildly dilated left atrium. AP, anterior‐posterior; AVD‐GP, atrioventricular‐dissociating ganglionated plexus; C‐HFS, continuous high‐frequency stimulation; ET‐GP, ectopy‐triggering ganglionated plexus; HFS, high‐frequency stimulation; INF, inferior; LAO, left anterior oblique; LIPV, left inferior pulmonary vein; LSPV, left superior pulmonary vein; PA, posterior–anterior; RAO, right anterior oblique; RF, radiofrequency; RIPV, right inferior pulmonary vein; RSPV, right superior pulmonary vein; S‐HFS, synchronized high‐frequency stimulation; SUP, superior

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  Figure 7. A scatter plot of the number of GPs (ET‐GP and AVD‐GP) identified in patients undergoing GP ablation. Sixteen patients who reached the primary end‐point had an average of 22 ± 9 GPs ablated. Fifteen patients who did not reach primary end‐point had an average of 19 ± 8 GPs ablated (p = .62). The longest line within the scatter plots represents the mean and the error bars represent standard deviation. AVD‐GP, atrioventricular dissociating ganglionated plexus; ET‐GP, ectopy‐triggering ganglionated plexus; GP, ganglionated plexus