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SNOWMASS, COLO. – Appropriate in the way of benefit, along with instilling awareness of the warning signals heralding serious late complications, Samuel J. Asirvatham, MD, said at the annual Cardiovascular Conference at Snowmass sponsored by the American College of Cardiology.
“Who to steer toward ablation? You have to have a symptomatic patient – that’s a given. For the ones who are paroxysmal, the ones with a relatively normal heart, there’s a much better chance that you’ll help manage their symptoms with ablation than if they have persistent or permanent A-fib. Notice I do not use the word ‘cure’ for A-fib. We talk about controlling symptoms and decreasing frequency, because the longer follow-up you have with intensive monitoring, the more you realize that patients still tend to have some A-fib,” explained Dr. Asirvatham, an electrophysiologist who is professor of medicine and pediatrics at the Mayo Clinic in Rochester, Minn.
The rationale for early atrial fibrillation (AF) ablation in younger patients with troublesome symptoms of paroxysmal AF despite pharmacologic attempts at rate or rhythm control is that it will arrest the progression from an atrial arrhythmia that has just a few triggers readily neutralized by pulmonary vein isolation to persistent AF with a diseased heart and a multitude of arrhythmia trigger points coming from many directions.
A solid candidate for ablation of paroxysmal AF has about a 75% likelihood of having a successful first ablation procedure, with substantial improvement in symptoms and no need for medication. Another 9%-10% will achieve marked reduction in symptom burden upon addition of antiarrhythmic agents that weren’t effective before ablation.
Late complications can be deceptive
Periprocedural stroke/transient ischemic attack, tamponade, or bleeding on the table are infrequent complications readily recognized by the interventionalist. More problematic are several late complications which are often misinterpreted, with the resultant delay causing major harm.
- Pulmonary vein stenosis. This complication of inadvertent ablation inside the pulmonary vein manifests as shortness of breath, typically beginning about 4 weeks post ablation.
“This is very different from the shortness of breath they had with atrial fibrillation. They almost always have a cough that they didn’t have before, and they may have hemoptysis. It’s very important to recognize this promptly, because before it closes completely we can do an angioplasty and stent the vein with good results. But once it closes completely, it becomes an extremely complicated procedure to try to reopen that vein,” according to Dr. Asirvatham.
Very often the patient’s general cardiologist, chest physician, or primary care physician fails to recognize what’s happening. He cited an example: He recently had a patient with a cough who was first referred to an infectious disease specialist, who ordered a bronchoalveolar lavage. The specimen grew atypical actinomycetes. That prompted a referral to thoracic surgery for an open-lung biopsy. But that procedure required cardiac clearance beforehand. It was a cardiologist who said, ‘Wait – all this started after you had an ablation?’
“That patient had pulmonary vein stenosis. And, unfortunately, that complication has not gone away. Being a referral center for pulmonary vein isolation, we see just as many cases of pulmonary vein stenosis today as we did a few years ago,” he said.
- Atrial esophageal fistula. The hallmark of this complication is onset of a plethora of what Dr. Asirvatham called “funny symptoms” more than a month post ablation. These include fever, transient ischemic attacks (TIAs), sepsislike symptoms, discomfort in swallowing, and in some cases hemoptysis.
“The predominant picture is endocarditis/TIA/stroke. If you see this, and the patient has had ablation, immediately refer to surgery to have the fistula between the esophagus and heart fixed. This is not a patient where you say, ‘Nothing by mouth, give some antibiotics, and see what happens.’ I can tell you what will happen: The patient will die,” the cardiologist said.
- Atrial stiffness. This typically occurs about a month after a second or third ablation procedure, when the patient develops shortness of breath that keeps worsening.
“You think ‘pulmonary vein stenosis,’ but the CT scan shows the veins are wide open. Many of these patients will get misdiagnosed as having heart failure with preserved ejection fraction even though they never had it before. The problem here is the atrium has become too stiff from the ablation, and this stiff atrium causes increased pressure, resulting in the shortness of breath. Sometimes patients feel better over time, but sometimes it’s very difficult to treat. But it’s important to recognize atrial stiffness and exclude other causes like pulmonary vein stenosis,” Dr. Asirvatham continued.
- Gastroparesis. This occurs because of injury to the vagus nerve branches located at the top of the esophagus, with resultant delayed gastric emptying.
“It’s an uncomfortable feeling of fullness all the time. The patient will say, ‘It seems like I just ate, even though I ate 8 hours ago,” the electrophysiologist said. “Most of these patients will recover in about 6 months. They may feel better on a gastric motility agent, like a macrolide antibiotic. I personally have not seen a patient who did not feel better within 6-8 months.”
Novel treatment approaches: “A-fib may be an autonomic epilepsy of the heart”
“Patients sometimes will ask you, ‘What is this ablation? What does that mean?’ You have to be truthful and tell them that it’s just a fancy word for burning,” the electrophysiologist said.
Achievement of AF ablation without radiofrequency or cryoablation, instead utilizing nonthermal direct-current pulsed electrical fields, is “the hottest topic in the field of electrophysiology,” according to Dr. Asirvatham.
These electrical fields result in irreversible electroporation of targeted myocardial cell membranes, leading to cell death. It is a tissue-specific intervention, so it’s much less likely than conventional ablation to cause collateral damage to the esophagus and other structures.
“Direct current electroporation has transitioned from proof-of-concept studies to three relatively large patient trials. This is potentially an important breakthrough because if we don’t heat, a lot of the complications of A-fib ablation will probably decrease,” he explained.
Two other promising outside-the-box approaches to the treatment of AF are autonomic nervous system modulation at sites distant from the heart and particle beam ablation without need for cardiac catheters.
“If you put electrodes everywhere in the body to see where A-fib starts, it’s not in the atrium, not in the pulmonary veins, it’s in the nerves behind the pulmonary veins, and before those nerves it’s in some other area of the autonomic nervous system. This has given rise to the notion that A-fib may be an autonomic epilepsy of the heart,” according to the electrophysiologist.
This concept has given rise to a completely different approach to treatment of AF through neurostimulation. That’s how acupuncture works. Also, headphones have been used successfully to terminate and prevent AF by stimulating autonomic nerve centers near the ears. Low-level electrical stimulation of the vagus nerve in order to reduce stellate ganglion activity is under study. So is the application of botulinum toxin at key points in the autonomic nervous system.
“Catheters, drugs, and devices that target these areas, maybe without any ablation in the heart itself, is an exciting area of future management of A-fib,” he said.
Another promising approach is borrowed from radiation oncology: particulate ablation using beams of carbon atoms, protons, or photons.
“The first patients have now been treated for ventricular tachycardia and A-fib. It really is quite amazing how precise the lesion formation is. And with no catheters in the heart, clot can’t form on catheters,” he observed.
Dr. Asirvatham reported having no financial conflicts regarding his presentation, although he serves as a consultant to a handful of medical startup companies and holds patents on intellectual property, the royalties for which go directly to the Mayo Clinic.
SNOWMASS, COLO. – Appropriate in the way of benefit, along with instilling awareness of the warning signals heralding serious late complications, Samuel J. Asirvatham, MD, said at the annual Cardiovascular Conference at Snowmass sponsored by the American College of Cardiology.
“Who to steer toward ablation? You have to have a symptomatic patient – that’s a given. For the ones who are paroxysmal, the ones with a relatively normal heart, there’s a much better chance that you’ll help manage their symptoms with ablation than if they have persistent or permanent A-fib. Notice I do not use the word ‘cure’ for A-fib. We talk about controlling symptoms and decreasing frequency, because the longer follow-up you have with intensive monitoring, the more you realize that patients still tend to have some A-fib,” explained Dr. Asirvatham, an electrophysiologist who is professor of medicine and pediatrics at the Mayo Clinic in Rochester, Minn.
The rationale for early atrial fibrillation (AF) ablation in younger patients with troublesome symptoms of paroxysmal AF despite pharmacologic attempts at rate or rhythm control is that it will arrest the progression from an atrial arrhythmia that has just a few triggers readily neutralized by pulmonary vein isolation to persistent AF with a diseased heart and a multitude of arrhythmia trigger points coming from many directions.
A solid candidate for ablation of paroxysmal AF has about a 75% likelihood of having a successful first ablation procedure, with substantial improvement in symptoms and no need for medication. Another 9%-10% will achieve marked reduction in symptom burden upon addition of antiarrhythmic agents that weren’t effective before ablation.
Late complications can be deceptive
Periprocedural stroke/transient ischemic attack, tamponade, or bleeding on the table are infrequent complications readily recognized by the interventionalist. More problematic are several late complications which are often misinterpreted, with the resultant delay causing major harm.
- Pulmonary vein stenosis. This complication of inadvertent ablation inside the pulmonary vein manifests as shortness of breath, typically beginning about 4 weeks post ablation.
“This is very different from the shortness of breath they had with atrial fibrillation. They almost always have a cough that they didn’t have before, and they may have hemoptysis. It’s very important to recognize this promptly, because before it closes completely we can do an angioplasty and stent the vein with good results. But once it closes completely, it becomes an extremely complicated procedure to try to reopen that vein,” according to Dr. Asirvatham.
Very often the patient’s general cardiologist, chest physician, or primary care physician fails to recognize what’s happening. He cited an example: He recently had a patient with a cough who was first referred to an infectious disease specialist, who ordered a bronchoalveolar lavage. The specimen grew atypical actinomycetes. That prompted a referral to thoracic surgery for an open-lung biopsy. But that procedure required cardiac clearance beforehand. It was a cardiologist who said, ‘Wait – all this started after you had an ablation?’
“That patient had pulmonary vein stenosis. And, unfortunately, that complication has not gone away. Being a referral center for pulmonary vein isolation, we see just as many cases of pulmonary vein stenosis today as we did a few years ago,” he said.
- Atrial esophageal fistula. The hallmark of this complication is onset of a plethora of what Dr. Asirvatham called “funny symptoms” more than a month post ablation. These include fever, transient ischemic attacks (TIAs), sepsislike symptoms, discomfort in swallowing, and in some cases hemoptysis.
“The predominant picture is endocarditis/TIA/stroke. If you see this, and the patient has had ablation, immediately refer to surgery to have the fistula between the esophagus and heart fixed. This is not a patient where you say, ‘Nothing by mouth, give some antibiotics, and see what happens.’ I can tell you what will happen: The patient will die,” the cardiologist said.
- Atrial stiffness. This typically occurs about a month after a second or third ablation procedure, when the patient develops shortness of breath that keeps worsening.
“You think ‘pulmonary vein stenosis,’ but the CT scan shows the veins are wide open. Many of these patients will get misdiagnosed as having heart failure with preserved ejection fraction even though they never had it before. The problem here is the atrium has become too stiff from the ablation, and this stiff atrium causes increased pressure, resulting in the shortness of breath. Sometimes patients feel better over time, but sometimes it’s very difficult to treat. But it’s important to recognize atrial stiffness and exclude other causes like pulmonary vein stenosis,” Dr. Asirvatham continued.
- Gastroparesis. This occurs because of injury to the vagus nerve branches located at the top of the esophagus, with resultant delayed gastric emptying.
“It’s an uncomfortable feeling of fullness all the time. The patient will say, ‘It seems like I just ate, even though I ate 8 hours ago,” the electrophysiologist said. “Most of these patients will recover in about 6 months. They may feel better on a gastric motility agent, like a macrolide antibiotic. I personally have not seen a patient who did not feel better within 6-8 months.”
Novel treatment approaches: “A-fib may be an autonomic epilepsy of the heart”
“Patients sometimes will ask you, ‘What is this ablation? What does that mean?’ You have to be truthful and tell them that it’s just a fancy word for burning,” the electrophysiologist said.
Achievement of AF ablation without radiofrequency or cryoablation, instead utilizing nonthermal direct-current pulsed electrical fields, is “the hottest topic in the field of electrophysiology,” according to Dr. Asirvatham.
These electrical fields result in irreversible electroporation of targeted myocardial cell membranes, leading to cell death. It is a tissue-specific intervention, so it’s much less likely than conventional ablation to cause collateral damage to the esophagus and other structures.
“Direct current electroporation has transitioned from proof-of-concept studies to three relatively large patient trials. This is potentially an important breakthrough because if we don’t heat, a lot of the complications of A-fib ablation will probably decrease,” he explained.
Two other promising outside-the-box approaches to the treatment of AF are autonomic nervous system modulation at sites distant from the heart and particle beam ablation without need for cardiac catheters.
“If you put electrodes everywhere in the body to see where A-fib starts, it’s not in the atrium, not in the pulmonary veins, it’s in the nerves behind the pulmonary veins, and before those nerves it’s in some other area of the autonomic nervous system. This has given rise to the notion that A-fib may be an autonomic epilepsy of the heart,” according to the electrophysiologist.
This concept has given rise to a completely different approach to treatment of AF through neurostimulation. That’s how acupuncture works. Also, headphones have been used successfully to terminate and prevent AF by stimulating autonomic nerve centers near the ears. Low-level electrical stimulation of the vagus nerve in order to reduce stellate ganglion activity is under study. So is the application of botulinum toxin at key points in the autonomic nervous system.
“Catheters, drugs, and devices that target these areas, maybe without any ablation in the heart itself, is an exciting area of future management of A-fib,” he said.
Another promising approach is borrowed from radiation oncology: particulate ablation using beams of carbon atoms, protons, or photons.
“The first patients have now been treated for ventricular tachycardia and A-fib. It really is quite amazing how precise the lesion formation is. And with no catheters in the heart, clot can’t form on catheters,” he observed.
Dr. Asirvatham reported having no financial conflicts regarding his presentation, although he serves as a consultant to a handful of medical startup companies and holds patents on intellectual property, the royalties for which go directly to the Mayo Clinic.
SNOWMASS, COLO. – Appropriate in the way of benefit, along with instilling awareness of the warning signals heralding serious late complications, Samuel J. Asirvatham, MD, said at the annual Cardiovascular Conference at Snowmass sponsored by the American College of Cardiology.
“Who to steer toward ablation? You have to have a symptomatic patient – that’s a given. For the ones who are paroxysmal, the ones with a relatively normal heart, there’s a much better chance that you’ll help manage their symptoms with ablation than if they have persistent or permanent A-fib. Notice I do not use the word ‘cure’ for A-fib. We talk about controlling symptoms and decreasing frequency, because the longer follow-up you have with intensive monitoring, the more you realize that patients still tend to have some A-fib,” explained Dr. Asirvatham, an electrophysiologist who is professor of medicine and pediatrics at the Mayo Clinic in Rochester, Minn.
The rationale for early atrial fibrillation (AF) ablation in younger patients with troublesome symptoms of paroxysmal AF despite pharmacologic attempts at rate or rhythm control is that it will arrest the progression from an atrial arrhythmia that has just a few triggers readily neutralized by pulmonary vein isolation to persistent AF with a diseased heart and a multitude of arrhythmia trigger points coming from many directions.
A solid candidate for ablation of paroxysmal AF has about a 75% likelihood of having a successful first ablation procedure, with substantial improvement in symptoms and no need for medication. Another 9%-10% will achieve marked reduction in symptom burden upon addition of antiarrhythmic agents that weren’t effective before ablation.
Late complications can be deceptive
Periprocedural stroke/transient ischemic attack, tamponade, or bleeding on the table are infrequent complications readily recognized by the interventionalist. More problematic are several late complications which are often misinterpreted, with the resultant delay causing major harm.
- Pulmonary vein stenosis. This complication of inadvertent ablation inside the pulmonary vein manifests as shortness of breath, typically beginning about 4 weeks post ablation.
“This is very different from the shortness of breath they had with atrial fibrillation. They almost always have a cough that they didn’t have before, and they may have hemoptysis. It’s very important to recognize this promptly, because before it closes completely we can do an angioplasty and stent the vein with good results. But once it closes completely, it becomes an extremely complicated procedure to try to reopen that vein,” according to Dr. Asirvatham.
Very often the patient’s general cardiologist, chest physician, or primary care physician fails to recognize what’s happening. He cited an example: He recently had a patient with a cough who was first referred to an infectious disease specialist, who ordered a bronchoalveolar lavage. The specimen grew atypical actinomycetes. That prompted a referral to thoracic surgery for an open-lung biopsy. But that procedure required cardiac clearance beforehand. It was a cardiologist who said, ‘Wait – all this started after you had an ablation?’
“That patient had pulmonary vein stenosis. And, unfortunately, that complication has not gone away. Being a referral center for pulmonary vein isolation, we see just as many cases of pulmonary vein stenosis today as we did a few years ago,” he said.
- Atrial esophageal fistula. The hallmark of this complication is onset of a plethora of what Dr. Asirvatham called “funny symptoms” more than a month post ablation. These include fever, transient ischemic attacks (TIAs), sepsislike symptoms, discomfort in swallowing, and in some cases hemoptysis.
“The predominant picture is endocarditis/TIA/stroke. If you see this, and the patient has had ablation, immediately refer to surgery to have the fistula between the esophagus and heart fixed. This is not a patient where you say, ‘Nothing by mouth, give some antibiotics, and see what happens.’ I can tell you what will happen: The patient will die,” the cardiologist said.
- Atrial stiffness. This typically occurs about a month after a second or third ablation procedure, when the patient develops shortness of breath that keeps worsening.
“You think ‘pulmonary vein stenosis,’ but the CT scan shows the veins are wide open. Many of these patients will get misdiagnosed as having heart failure with preserved ejection fraction even though they never had it before. The problem here is the atrium has become too stiff from the ablation, and this stiff atrium causes increased pressure, resulting in the shortness of breath. Sometimes patients feel better over time, but sometimes it’s very difficult to treat. But it’s important to recognize atrial stiffness and exclude other causes like pulmonary vein stenosis,” Dr. Asirvatham continued.
- Gastroparesis. This occurs because of injury to the vagus nerve branches located at the top of the esophagus, with resultant delayed gastric emptying.
“It’s an uncomfortable feeling of fullness all the time. The patient will say, ‘It seems like I just ate, even though I ate 8 hours ago,” the electrophysiologist said. “Most of these patients will recover in about 6 months. They may feel better on a gastric motility agent, like a macrolide antibiotic. I personally have not seen a patient who did not feel better within 6-8 months.”
Novel treatment approaches: “A-fib may be an autonomic epilepsy of the heart”
“Patients sometimes will ask you, ‘What is this ablation? What does that mean?’ You have to be truthful and tell them that it’s just a fancy word for burning,” the electrophysiologist said.
Achievement of AF ablation without radiofrequency or cryoablation, instead utilizing nonthermal direct-current pulsed electrical fields, is “the hottest topic in the field of electrophysiology,” according to Dr. Asirvatham.
These electrical fields result in irreversible electroporation of targeted myocardial cell membranes, leading to cell death. It is a tissue-specific intervention, so it’s much less likely than conventional ablation to cause collateral damage to the esophagus and other structures.
“Direct current electroporation has transitioned from proof-of-concept studies to three relatively large patient trials. This is potentially an important breakthrough because if we don’t heat, a lot of the complications of A-fib ablation will probably decrease,” he explained.
Two other promising outside-the-box approaches to the treatment of AF are autonomic nervous system modulation at sites distant from the heart and particle beam ablation without need for cardiac catheters.
“If you put electrodes everywhere in the body to see where A-fib starts, it’s not in the atrium, not in the pulmonary veins, it’s in the nerves behind the pulmonary veins, and before those nerves it’s in some other area of the autonomic nervous system. This has given rise to the notion that A-fib may be an autonomic epilepsy of the heart,” according to the electrophysiologist.
This concept has given rise to a completely different approach to treatment of AF through neurostimulation. That’s how acupuncture works. Also, headphones have been used successfully to terminate and prevent AF by stimulating autonomic nerve centers near the ears. Low-level electrical stimulation of the vagus nerve in order to reduce stellate ganglion activity is under study. So is the application of botulinum toxin at key points in the autonomic nervous system.
“Catheters, drugs, and devices that target these areas, maybe without any ablation in the heart itself, is an exciting area of future management of A-fib,” he said.
Another promising approach is borrowed from radiation oncology: particulate ablation using beams of carbon atoms, protons, or photons.
“The first patients have now been treated for ventricular tachycardia and A-fib. It really is quite amazing how precise the lesion formation is. And with no catheters in the heart, clot can’t form on catheters,” he observed.
Dr. Asirvatham reported having no financial conflicts regarding his presentation, although he serves as a consultant to a handful of medical startup companies and holds patents on intellectual property, the royalties for which go directly to the Mayo Clinic.
REPORTING FROM ACC SNOWMASS 2019