Dr Ayinde discusses his session at Heart Rhythm 2023, which took place May 19-21, 2023.

Transcripts:

I am Hakeem Ayinde. I am an electrophysiologist at Cardiology Associates of Fredericksburg in Virginia. I am here at Heart Rhythm 2023 moderating a session on cardioneuroablation (CNA) for the treatment of functional bradycardia and also as adjunctive treatment for atrial fibrillation (AF). The session was very well attended—it was standing room only. We had excellent speakers. We had Dr Samuel Asirvatham describing the anatomy of the parasympathetic nervous and sympathetic innervation of the heart. We had Dr Tolga Aksu discussing the use of CNA in treating functional bradycardia. Dr J.C. Pachon, who is the pioneer of CNA, gave a talk about the use of CNA as adjunctive treatment in AF. He has an upcoming publication showing improved outcomes vs pulmonary vein isolation alone. Finally, Dr Roderick Tung talked about CNA and where we are at right now, other considerations, and how this can get in the guidelines. My co-moderator was Dr Jeffrey Winterfield from the Medical University of South Carolina. So, this session definitely included very powerful voices in electrophysiology (EP)—it was a “can’t miss” session!

Importantly, one of the take-home points that I'd like share is on patient selection. Which patients will benefit from CNA? We have this EP procedure that sounds great, but will my patient benefit from it? The important thing to know is if this is functional bradycardia, so you will need to do some testing. This includes either a head-up tilt table test, a Holter monitor, or loop recorder. One of these tests will need to demonstrate functional bradycardia or cardioinhibitory syncope. Also, older patients are more likely to have more degenerative disease, probably sinus node dysfunction or atrioventricular (AV) node block that may be more pathologic vs functional over the age of 60. Importantly, giving 2 milligrams of atropine can help highlight the patients who truly have functional bradycardia, because if it's sinus bradycardia, you will see an increase in sinus rates. If it is a functional AV block, you will see resolution of AV block after atropine. Because atropine stays in the body for about 4 hours, if you are going to do CNA, just do it on a different day, not the same day you administer atropine.

For a brief overview of the CNA procedure, we generally know the locations of the left and right atrial ganglia. For the left atrial ganglia, you have the left superior ganglion plexus on the roof just above the left superior vein. The left inferior ganglia are posterior-inferior to and a little on the posterior wall behind the left inferior pulmonary vein. The Marshall Tract ganglion plexus are on the ridge by the vein of Marshall just anterior to the left veins. Those left ganglion plexuses generally control AV node function. The right superior ganglion plexus is anterior to the right superior pulmonary vein. The right inferior ganglion is posterior-inferior to the right inferior pulmonary vein. The PML ganglion plexus is inferior and close to the coronary sinus OS. Then, in the right atrium, we have the superior vena cava (SVC)/aortic ganglion plexus. So, in general, the right superior ganglia and SVC/aortic ganglia correlate to control of the sinus node. One thing to know when you approach this is that there is hierarchical control of the parasympathetic innervation of the heart, such that if, for example, you want to treat functional AV block, it's better to treat the left ganglia first before treating the right ganglia, and that's because if you treat the right ganglia first, you may not see the effects of treatment of the left ganglia, because the right ganglia supersedes. There's an interconnectivity between the ganglia. So, my approach is to treat the left ganglia first before you go to the right ganglia. But if you want to treat functional sinus bradycardia, you can go directly to the right because they control more of the sinus node function. Then, when we look at long-term outcomes, the best data we have is from Dr Pachon. He has 2-year data showing that about 90% of patients are symptom free at 2 years. We do see some reinnervation, but for the most part, it's a pretty good that after 2 years these results are durable. We have a lot of young patients. Most of my patients are between the age of 18 and early 30s, but a lot of them are in their 20s. These are people who have passed out multiple times and are very frustrated—sometimes even going on disability—but we now have a procedure that can give them their life back with great quality of life and long-term outcomes.

So, I think the future is very bright for CNA and we look forward to more publications and data. The other thing I'll say is that data is very important. For a lot of these patients, let’s be sure to give them Holters or loop recorders to gather more data and altogether understand the long-term outcomes to better refine this, hopefully get CNA into the guidelines, and get it FDA approved.