CNA Conference - Dr. Pedro Adragao - What to do with symptomatic overtraining bradycardia? Is there a place for CNA?

So, up next, we have Doctor Pedro Adrigao. Uh, Doctor Adrigao is from the Hospital Daluz in Lisbon, and he is going to talk with us about what to do with symptomatic overtraining bradycardia. Is there a place for CNA? Good morning. I would like to thank Professor Passion for the invitation to participate in the 2nd World Symposium on cardio neuroablation. It is a pleasure to share our experience with the pioneers of this promising technique. The aim of our talk is to explore the value of cardio neuroablation, to treat symptomatic overtraining bradycardia. Vigorous exercise is associated with structural, functional and electrical art changes, usually referred as athlete's art. In fact, athletes usually have sinus bradycardia and or sinus pulse, atraventricular block, left ventricular hypertrophy, right bundle branch block, and may have abnormal T wave inversion. These electrical changes may be asymptomatic and are usually benign. However, some overtrained individuals become symptomatic and may may need individualized treatment, especially, they may have sinus bradycardia below 30 beats per minute and 1 degree AV block. We have here an example of an amateur athlete, a soccer player with a sinus rest with more than 66 seconds, and after suspension of the exercise with a follow-up of 6 years, it's completely normalized. In fact, exercise suspension is often recommended as first line treatment, and if not effective, pacemaker implantation has been accepted as a treatment by the guidelines. Although the guidelines of 2013 as an indication2A. Today, for pauses, more than 6 seconds, as symptomatic pauses, or sync, recurrent syn in 2021 guidelines is only a class 2B. Paympactic overactivity may be the major cause of several clinical bradyarrhythmias. The autonomic control of the heart is mediated by more than 1000 epicardial autonomic ganglia. These neurons converge into autonomic GPs that are embedded in epicardial fat pads. The GPS contains both efferent sympatic and parasymppatic neurons. Cater-based ablation of GPs, cardio uh cardiac neuroablation, has gained attention as a novel, effective therapy to treat vagal syncope and the functional vagally mediated AV block. The first description of cardio neuroablation was done by Passon and Carl Paponi, who referred that vagal attenuation could significantly increase the success rate of paroxysmal atrial fibrillation ablation. Soon after, a new treatment was clearly defined by Professor Passion, the cardio neuroablation to treat vasovagal sync, functional AV block, and sinus dysfunction. A long period of discussion occurred, and the more detailed anatomical location of an autonomic nervous system GP were described by Nakagawa and by Pascho. Today, we are speaking of results of this strategy. There are several small scale retrospective analyses showing very good results for cardio neuroablation, although the placebo effect could not be excluded. A randomized trial, Roman one study, including 48 patients with carbonviory sync, confirmed these observational results, with 92% of zinc-free survival as 2 years of follow-up. Also, a meta-analysis of 14 studies, including more than 400 patients had similar results of sin-free survival, 92%. There are several protocols to define candidates to cardio neuroablation. The most suitable patients would be younger, usually less than 40 years old, with cardio inventory sys. Between 40 and 60 years old, an individualized approach is recommended, either for CNA or pacemaker implantation. Above 60 years old, pacemaker implantation is preferred. If one of these treatments is not effective, we can always use the second one. Last, as Congress, uh, viol that is in the guidelines for pacemaker implantation and sync. Uh, explain how it, uh, it was possible to carry out the cardio neuroablation. For him, it was necessary to identify a proper candidate with tilt the, uh, tilt test or by event recorder after ablate the proper ganglia, after verify the results with the uh asymptomatic patients, heart rate variability, increase the heart rate, no syncopal recurrence. And also it was necessary to prove the uh efficacy of treatment with randomized trial of large scale and need for long follow-up. Although cardio ablation can be effective, according rnoli is not an indication for generalized use. According to the clinical experience of the teams in symptomatic severity of the patient's recurrent symptomatic episodes and or traumatic symptoms, we may advise treatment, we may consider it appropriate, and we also may consider it not indicated. But today, we are not speaking about conventional guidelines. You are, we are speaking about the new treatment and very recently, this Polish team published with Sebastian Steck showed that the possibility to stop a pacemaker in patients with pacemaker implantation. In a group of 200 patients referred to clinical evaluation and cardio neuroablation, 20 patients had permanent pacemaker. They performed electrophysiologic tests and extra cardiac vagal stimulation, and if the test EP test was negative, cardio neuroablation was performed. This means that 90 patients of the 20 patients of the group could discontinue the the pacemaker, so they can stop pacing. In the follow-up of 18 months, they have no symptoms, and the only patient that had not stopped uh uh the the pacing was a patient with an episthetic was positive and did not perform cardio neuroablation. So we are thinking about a different approach from the conventional guidelines. Today, in 2023 in our hospital, we have a simple protocol that we include patients with sinus rhythm during ablation that have severe cardioinviatory vagal synd, functional AV block, and sinus node dysfunction. We have some exclusion criteria like severe asthma, pacing, permanent pacing, prior arterial ablation procedures, structural heart disease, and or heart failure. We use partial neurostimulant to perform extracardiac vagal stimulation, considering positive. If the high frequency stimulation induced pause is more than 3 seconds, increase RR interval more than 20%, or induce a 2nd or 3rd degree AV blocks, or increase AH interval more than 20 milliseconds. Our targets are the right and left atrium GPs. Sinus node GPs are right superior GPs, left superior GP. For AV block, AV node GPs are postoral medial left GPs, martial tract GPs, and posterolateal GPs as described by Passion. Our initial experience report of 30 patients was done with the treatment of atrial right GPs only, with an excellent short-term results, no, no recurrences at 8 months follow-up. Now I will uh uh show you some uh case reports uh in athletes. Showing the first case report is a cardio neuroablation performed in a 42-year-old marathonist referred for pacemaker implantation due to high degree AV block with pauses more than 5 seconds. The mean heart rate increased 50% without AV block after cardio neuroablation. No clinical relapse despite maintaining exercise training that you could not suspend due to endorphins additive effect. You see here 43 beats in the watch. Goes to 52 resting heart rate. The second case is of a 40 year old patient, swimmer. We can see the systole induced by the neurostimulation during Epi study. We have then fascinating map with insight software. Described by Pasho. You see your multifractionated electrograms that we can see in this uh mapping. And we have done the ablation of the GPS and this multi-fast. Electrograph, right and left atrial ablation. The final EI ECG increased to 84 beats per minute. It was before treatment, 50 beats per minute. No, no pauses during the extra cardiac vagal stimulation. And uh one year follow-up, the patient was asymptomatic without recurrence events in the event recorder that they had implanted. Another cardio neuroablation in a 42 year old jogging and cycling patient with multiple cardio inventory symptoms and some episodes of trauma. Sinus bradycardia with the atrioventricular block before neurocardial ablation when stimulated with high frequency stimulation, and no AV block after ablation and the neuro stimulation. Another case of a 15-year-old basketball player with sync, routine ECG with a 2nd degree AV block Movis one, and the author with a medium march rate of 70 beats per minute at high degree AV block with pauses, longest pauses more than 5 seconds. You can see neurostimulation before and after ablation, excel in short-term follow-up, asymptomatic at 6 months, uh, a follow-up, maintains regular sports activity. The last example is a 34 year old equestrian, multi-dramatic sips, high degree AV block on 24 hour rotor, more than 7 seconds of pauses, a tilt test with a positive answer, mixed responses. Before ablation, 59 R beats per minute, and after ablation, 104 beats per minute. We have done an anatomical approach in relation mapping, and is here the high frequency multiphasic uh electrographs and Both, both sides, right and left ablation, and immediately after the cardio neuroablation in 2019, Minnard rate 94 per minute, no pulses, nor AV block. One year after cardio neuroablation 2020, Minzar rate 87 beats per minute, no pulse nor AV block. A short heart rate variability, but 2 years after ablation, mean heart rate 82 beats per minute, no pulse, no AV blocks, and is completely asymptomatic during normal life. After 4 years, asymptomatic equestrian practice 4 days a week. To conclude, cardio ablation in overtrained athletes, exercise training is disseminated in normal population. Many will develop broadly related symptoms. Cardio neuroablation indications are cardio inventoryy due to sinus pulse or and high degree AV block. Cardio neuroablation is better in younger than 50 years old responders to atropine, non-responders to conventional therapy. Best approach to to is necessary to be defined, anatomical right and left side, endocardial mapping with high amplitude fragmented electrograms, eye frequency stimulation evaluation. In fact, cardio neuroablation is highly successfully therapy. More than 90% of patients are symptomatic during the follow-up. There are few limitations, few data in short-term follow-up, lack of randomized data, positive effect, no sham studies, evaluate relapses with or without maintenance of exercise training. We need clear clinical guidelines to to do recommendations for cardio neuroablation and also to recommendation of ablation for the subgroup of vagotonic athletes. Thank you very much. Thank you, Doctor Edrigal. We appreciate you being here and very much appreciate your experience and your knowledge and your willingness to share that with us today. Thank you. I have uh one question for you. If you have an Olympic runner. With prolonged pauses. Would you even consider exercise restriction or pacemaker today? I may consider, but he will not wait for that, and he will not want the decision, so he will not do. Uh, I think that uh we have here a very good solution to avoid pacemaker and to maintain the, uh, the exercise. In fact, all of our patients have not stopped exercise, even though if you ask for the marathon is to reduce the. Uh, it was impossible. He, he, but after two months it wasn't the same thing. So, he, he, he thought that it was very good, so he, he didn't want to, to stop the exercise. Uh, the endorphins are an important problem for them. They need that. So, or they get depressive or they go on walking, exercising, so it's difficult. Thank you. One question from Amaret Nawar. Do you always get 100% vagal response with ECVS in all cases? I've had successful can response despite no or minimal. Excess response in some cases. I, I, I think that it's not possible to have anything with 100% success. So this is the first thing. And we need to, to be sure that some patients are nonresponders because they also may have disease of the, of the structure. So uh if we want for older patients, we have uh uh less responses uh people. But even in the uh older patients, there are people that do a lot of exercise and do Stress test normal. They have an increase of heart rate that it's normal and they may have benefit before implanting a pacemaker to try to reduce this lower heart rate and to reduce the AV block uh that may be functional because they disappear uh with stress test and they are not increasing with stress, stress test. Hi, hi, uh, Doctor Pedro is a, um, uh, uh, an honor to be here, to, to be, to have your participation in this meeting. It's an honor for us. Uh, Doctor Aderagaon, uh, honored to be a very good friend, uh, he's professor of, uh, most of electrophysiologies in South America and in Brazil. So thank you very much for your participation. I would like to, to, to have your impression about the possibility of a change of the exercise performance after cardio neur ablation. Do you have been seen any modification of the exercise performance after cardio neation? Uh, so it's an excellent, uh, comment because, uh, usually, the, uh, athletes does not like to have an increase in the rate. They don't like it. And we need to tell them that it will be, uh, uh, it will be not as the beginning. Beginning maybe too high and after they are decrease. What we ask them is not to to stress that a lot because they may reduce more than necessary. So I think they don't. Reduce the, the results. They have good results, but in the beginning, they are afraid that they decrease the, the quality of the, the results. Uh, in my experience with 6 months, after 6 months, they are very happy with the solution. And uh we have uh other patients that are not uh athletes, but there's a very dangerous uh veins before, even the tetraplegic people that are asking for a pacemaker and that's a benign thing because uh uh uh uh they, they have no, no, they are not lucky and they had a, a, a problem, a very severe problem. There's the last case, they arrived, uh, in my office with 55 years old. We have done a tilt test. We verified that it was clearly a vagal symptom. We asked them before the pacemaker to try to, to do a uh uh neuro cardiac neuroablation, and he's fantastic. He reproduced the episodes of vagal episodes, but no pulses at all, no. So I think that we have a, a large, a large ambience to, to treat patients that, and we need to change the guidelines in this aspect. Thank you, Pedro. Nice to see you. I'm sorry, we, we only have time for one more question, and, uh, but I'm gonna take it. Any, uh, this is from Javier Banks. Any case that you've needed to repeat ablation for more complete denervation? Yes. Uh, I have one case that I, I had to repeat the ablation, and it was a good case because we thought in the beginning that we have not attained the ideal places to ablate. The increase of heart rate is absolutely necessary when we are ablating. If, if you don't find it because they're anatomically. It's not, uh, nearly where we asked for. Uh, sometimes it's, uh, our mistake and you need to do better. If you can, you need to, to take the possibility and if it relapses because the, the system also recover, we can do a second chance like in an atrial fibrillation ablation. Thank you very much. And unfortunately, there are other questions we're not gonna be able to get to, but we will remind the audience that those will be answered. We will forward them to the speaker. So, Doctor Adrigao, thank you so much. Bye.