The Value Of Right Anterior Ganglion Plexus Ablation In Cardiac Nerve Ablation And Circumferential Pulmonary Vein Isolation

Part I:The value of right anterior ganglion plexus ablation in cardioneuroablationBackground:Cardioneuroablation is an innovative treatment for vasovagal syncope(VVS),intermittent atrioventricular block and sinus node dysfunction.The cardiac autonomic ganglion plexus,which located in the epicardial fat pads,are the key structures to integrate the autonomic nerve information and are the primary targets of cardioneuroablation.In previous work,we performed simplified autonomic denervation via catheter ablation of GPs in the left atrium(LA)as therapy to the VVS and obtained excellent long-term clinical outcomes.We observed immediate increase of heart rate during catheter ablation on right anterior ganglionated plexus(RAGP),which is not observed during ablation at other ganglion plexus of LAObjective:The aim of this study is to assess the effects of ablation of GPs on heart rate and to observe the acute,short and long-term effect post cardioneuroablation.Methods:A total of 115 consecutive patients with VVS who underwent cardioneuroablation were enrolled.GPs of the LA were identified by high-frequency stimulation(HFS)and anatomical landmarks being targeted by radiofrequency catheter ablation.The GPs were ablated as order of Left superior GP(LSGP)-Left inferior GP(LIGP)-Right inferior GP(RIGP)-RAGP.Surface ECG and Intracardial ECG were recorded by multichannel recorder during procedure.Sinus node recovery time and Wenckebach cycle were recorded before and after cardioneuroablation procedure.Electrocardiogram and 24-hour Holter were reexamined 3 months after the operation and then reexamined every 6 months.Results:During HFS,the LSGP was the most common GP site at which a vagal response was observed(71 of 115,61.7%).Vagal responses were observed for 45(39.1%),56(48.3%),and 46(40.0%)times in LIGP,RAGP,and RIGP,respectively.The frequency of the vagal response during HFS between four GP sites were significantly different(P<0.001).During GPs ablation,vagal response in LSGP was also more frequently observed(87 of 115,75.7%).Vagal responses were observed for 52(44.8%),47(40.5%)and 43(37.1%)times in LIGP,RAGP,and RIGP,respectively.The difference of the vagal response between four GP sites were significant during GPs ablation(P<0.001).During ablation of RAGP,heart rate increased from 61.3 ± 12.2 to 82.4 ± 14.7(P<0.001),while there were just vagal responses observed during ablation of other GPs.Compared with baseline,the sinus node recovery time was decreased significantly from 1621.1±455.7 ms to 1021.4±217.6 ms(P<0.001),and the Wenckebach cycle decreased from 431.6±117.1 ms to 327.3±98.7ms(P<0.001)after cardioneuroablation procedure.During a follow-up of 21.4±13.1 months(median of 18 months),106(92.2%)participants had no recurrence of any episode of syncope or prosyncope.Holter data shown that minimal heart rate significantly increased at all follow-up time points(all P<0.05)and mean heart rate remained higher than baseline 12 months after ablation(P=0.001).Conclusion:Cardioneuroablation via GPs ablation in LA effectively inhibited the recurrence of VVS.Ablation on RAGP could increase heart rate immediately and remain for long term.This unique phenomenon may provide a new potential approach for the treatment of neural reflex syncope or brady-arrhythmias.Part Ⅱ:Impact of the order of targeted ganglion plexus on the heart rate and vagal response during cardioneuroablationBackground:Cardioneuroablation ablate ganglion plexus of the heart,can inhibit abnormal hyperactive vagal tone,and play a significant effect on refractory vasovagal syncope and autonomic nerve related bradyarrhythmia.The part I of this study demonstrated that catheter ablation on right anterior ganglionated plexus(RAGP)significantly increased the heart rate within seconds,which is the most important target of cardioneuroablation.However,due to the part I of this study is retrospective analysis,it cannot exclude that the ablation effect of the right anterior ganglion plexus is due to the cumulative effect of ablation of all other ganglion plexus of left atrium.Objective:The aim of this study is to investigate the impact of the order of targeted ganglionated plexus on the heart rate and vagal response during cardioneuroablation,and further clarify the regulatory mechanism of ganglion plexusMethods:A total of 28 consecutive patients with VVS who underwent cardioneuroablation were enrolled.All patients were prospectively randomly divided into two groups:the group A was ablated as order of Left superior GP(LSGP)-Left inferior GP(LIGP)-Right inferior GP(RIGP)-RAGP;the group B was ablated as RAGP-LSGP-LIGP-RIGP.Surface ECG and Intracardial ECG were recorded by multichannel recorder during the whole procedure.The response characteristics of each ganglion plexus were analyzed during the procedure.Sinus node recovery time and Wenckebach cycle were recorded before and after cardioneuroablation procedure.As a quantitative evaluation of the cardiac vagal tone,the deceleration capacity(DC)was recorded before and 24 hours after cardioneuroablation.Electrocardiogram and 24-hour Holter were reexamined 3 months after the operation and then reexamined every 6 months.Results:During high-frequency stimulation(HFS)at LSGP,LIGP,RIGP and RAGP sites,there was no significant difference in the vagal response induced by HFS between the two groups(all P>0.05).In Group A,the frequency of vagal response induced by ablation in LSGP,LIGP,RIGP and RAGP was 11(78.6%),5(35.7%),4(28.6%)and 2(14.3%)respectively.In Group B,two patients had vagal response during ablation of RAGP.After ablation of RAGP,the vagal response was significantly inhibited during ablation of the other GPs of left atrium(LSGP:1 patient;LIGP:0 patient;RIGP:0 patient).During ablation of LSGP,LIGP and RIGP In Group A,the heart rate of the patients did not have difference with the baseline before ablation.When RAGP was ablated,the heart rate of the patients increased significantly within few seconds.In group B,the heart rate increased significantly when the ablation began with RAGP,while did not increase furtherly when LSGP,LIGP and RIGP continued to be ablated.Compared with baseline,the sinus node recovery time,Wenckebach cycle and DC decreased significantly after cardioneuroablation procedure(all P<0.05).During the follow-up period(median of 9 months),there was no recurrence of syncope in both groups.One patient in Group A and two patients in group B had presyncope episode,with no significant difference between two groups(P=0.599).Conclusion:This study demonstrated that the order of GPs targets affects the heart rate and the frequency of vagal response during cardioneuroablation.Ablation of the RAGP firstly can inhibit the vagal response during the ablation of other GPs in the left atrium,which demonstrated that the RAGP is a key nerve pathway for the vagal response.The ablation strategy with RAGP ablated firstly can increase the procedural safety of cardioneuroablation.Part III:The value of right anterior ganglion plexus ablation in circumferential pulmonary vein isolationBackground:Circumferential pulmonary vein isolation(CPVI)is the cornerstone of the ablation procedure for atrial fibrillation.The cardiac autonomic ganglion plexus(GPs)which located near the epicardial fat pads and Marshall ligament are the key structures of the autonomic nervous system to integrate autonomic nervous information of the heart.Due to the locations of GPs are spatially closed to pulmonary veins,CPVI with unavoidable coincidental ganglionated plexus modification frequently induces vagal responses(VRs)and often requires back up pacing and/or administration of atropine during procedure.Our previous study found that the ablation of the right anterior ganglion plexus(RAGP)resulted in a unique effect of significantly increased heart rate,which indicated that RAGP is the primary center for regulating other GPs of the left atrium.Objective:The aim of this study is to assess the effect of RAGP ablation on vagal response(VR)during CPVI.Methods:A total of 80 patients with paroxysmal atrial fibrillation who underwent the first time CPVI were prospectively enrolled and randomly assigned to two groups:group A(n=40),CPVI started with right PVs at RAGP site;group B(n=40):CPVI started with left PVs first and the last ablation site is RAGP.The frequency of positive VR in each GP site was recorded during CPVI procedure.Electrophysiological parameters include basal cycle length(BCL),A-H interval,H-V interval,sinus node recovery time(SNRT)and atrioventricular node Wenckebach point(AV node WP)were recorded before and after CPVI procedure.Results:During CPVI,the positive VR were only observed on 1 patient in Group A and 25 patients in Group B(P<0.001).A total of 21 patients with positive VR in Group B needed for temporary ventricular pacing during procedure,while the only patient with positive VR in Group A did not need for temporary ventricular pacing(P<0.001).Compared with baseline,BCL,SNRT and AV node WP were decreased significantly after CPVI procedure in both groups(all P<0.05)and without differences between two groups.Conclusions:Ablation of the RAGP can effectively inhibit the VRs and increase the heart rate during CPVI procedure,thus improving the procedural safety of CPVI for the treatment of paroxysmal atrial fibrillation.