Dr. John Day of the Intermountain Heart Institute, discussed how A-Fib doubles the risk of having a silent stroke. Many studies have shown that A-Fib is independently associated with dementia. “AF is associated with a higher risk for cognitive impairment and dementia, with or without a history of clinical stroke.”
In one study of 11,723 patients, those with arrhythmia were 4½ times more at risk of developing dementia.
Dr. Day described four possible mechanisms that may lead to A-Fib dementia:
1. Macro/Micro Thromboembolism (strokes)
2. Cerebral Bleeds
3. Weakened Cerebral Blood Flow
4. Systemic Inflammation
For more details about A-Fib and dementia, read my complete summary of Dr. John Day’s 2015 AF Symposium report.
Risks of Cerebral Lesions & Cognitive Impairment: Living With A-Fib More Dangerous Than Having An Ablation
AF Symposium 2015
Dr. Josef Kautzner of the Institute for Clinical and Experimental Medicine, Prague, Czech Republic gave a presentation entitled “Periprocedural Microembolization During AF Ablation—Mechanisms, Incidence and Clinical Significance.”
Dr. Kautzner’s agenda included demonstrating that living with “AF is more dangerous than its ablation.”
Silent Brain Lesions after Ablation?
Recent studies of mesh-type multielectrode catheters (not yet FDA-approved for use in the US) using MRIs of the brain have revealed silent cerebral ischemia—small lesions on the brain that don’t seem to produce any symptoms and tend to disappear over time. Worldwide experience suggests that small and medium lesions (less than 10mm) disappear at follow-up, while larger than 10 mm lesions remain. These larger lesions make up only a small proportion of the silent lesions found.
Dr. Kautzner pointed out that these silent lesions are common in many interventional procedures such as carotid artery stenting (37%) and TAVI (replacing the Aortic Valve) (68%-77%).
Though these small cerebral lesions don’t seem to cause symptoms, obviously doctors want to avoid creating any kind of lesions on the brain if at all possible.
Cognitive Dysfunction after Ablation?
…by 90 days the POCD rates had dropped down to 13% of paroxysmal and 20% of persistent.
Persistent patients had linear ablation lines added and ablation of complex fractionated electrograms (CFAEs). They also underwent more cardioversions during the procedure than paroxysmal patients. 1
Silent Brain Lesions Before Ablation of Greater Concern
Of greater concern are the silent brain lesions which occur frequently before ablation. In MRI tests, a high proportion of A-Fib patients before ablation had silent cerebral infarctions or lesions (60%-80%). But the problem is that similar lesions were detected by MRI even in patients without documented A-Fib. Therefore, we still do not know how much A-Fib contributes to the development of such lesions. On the other hand, their presence may explain (at least in part) the association between A-Fib and dementia.
We still do not know how much A-Fib contributes to the development of such lesions but their presence may explain the association between A-Fib and dementia.
In one study 89% of paroxysmal and 92% of persistent A-Fib patients had at least one area of SCI (Silent Cerebral Ischemia). The number of SCI areas was higher in patients with persistent A-Fib. These silent brain lesions are associated with dementia. 2
Cognitive performance was significantly worse in patients with paroxysmal and persistent A-Fib than in controls in sinus rhythm. 3
How Silent Brain Lesions Develop During an Ablation
Dr. Kautzner described how these lesions might develop:
• Thrombi due to activation of the coagulation cascade after introduction of catheters. That’s why heparin and other anticoagulants are used before, during and after an RF ablation
• Particulate emboli (char)—making RF burns can potentially produce charring where small particles of heart tissue can break off and travel to the brain. This can be prevented by catheter cooling (irrigated-tip catheters) and prevention of tissue overheating
• Gaseous emboli (micro-bubbles) produced by air on sheaths/catheters or by heating/boiling of blood and heart tissue “steam pops.” Prevention—as above
Preventing Silent Brain Lesions During an Ablation
Dr. Kautzner described the procedures his center follows to prevent silent brain lesions:
• If CHA2DS2-VASc score of 0-1, no prior anticoagulation
• All others have uninterrupted warfarin (persistent have TEE before ablation)
• Aggressive heparinization from the beginning of the procedure, immediately after venous puncture
• Use of intracardiac echocardiography to monitor the procedure
The success of these strategies was documented in a study where DW-MRI and protein S100B testing were performed both before and the next day after the ablation. (DW stands for Diffusion Weighted Imaging MRI which is more sensitive in detecting small & early infarcts [lesions or tissue deaths]).
S100B testing checks the blood for calcium-binding proteins coming from the brain after a stroke. They predict post-ablation brain injury.
S100B testing checks the blood for calcium-binding proteins coming from the brain after a stroke. They predict post-ablation brain injury. In the example from Dr. Kautzner’s center, 1.7% of ablation patients had a new MRI lesion, while 5% had an increase of plasma S100B. (Plasma S100B testing seems to reveal more potential brain damage than an MRI and is certainly easier and cheaper to perform.)
Predictors of Post-Ablation Brain Injury Detected by Plasma S100B Testing
• Persistent A-Fib
• Procedure duration
• Cumulative dose of heparin (ACT—Activated Clotting Time)
• Cardioversion during the procedure
• CHA2DS2-VASC score
• Amount of RF burns. Patients who had a simple PVI ablation had fewer silent lesions than if linear lesions had to be made. If ablation for CFAEs had to be made, they had even more chance of silent lesions
• Single vs two transseptal punctures
Proposed Strategies to Minimize Risk of Silent Lesions
• Avoid interruption of anticoagulation before ablation
• Use TEE or ICE to detect any thrombus
• Systemic heparin from the beginning of the procedure
• Meticulous management of transseptal sheaths and catheters (including submersion of sheath assembly when loading with special catheters to avoid air bubbles on the sheaths)
• If using phased mesh RF catheters, avoid simultaneous activation of overlapping electrodes
• Consider avoidance of cardioversion during the ablation
Dr. Kautzner’s Conclusions
• Post-ablation asymptomatic cerebral microembolism can be detected with variable frequency
• Clinical consequences are unclear—some studies suggest possible cognitive decline
• On the other hand, there is much stronger evidence that atrial fibrillation is associated with a substantial risk of asymptomatic cerebral lesions and cognitive impairment
• Assessment of procedure-related brain damage (using DW-MRI or protein S100B) should become a standard for the monitoring of safety of novel technologies for ablation
A-Fib More Dangerous to Cognitive Ability than its Ablation: We are most grateful to Dr. Kautzner for his comprehensive study of A-Fib silent brain lesions. The bottom line is that there is inconclusive evidence that ablations produce lasting linear brain lesions and cognitive decline.
On the other hand, we know from many studies that A-Fib (before ablation) produces silent brain lesions in nearly 90% of cases and that these silent lesions are associated with dementia. Cognitive performance is significantly worse in people with A-Fib (both paroxysmal and persistent). As Dr. Kautzner says, “A-Fib is more dangerous than its ablation,” with regards to silent brain lesions and cognitive ability.
Importance and Frequency of Silent Brain Lesions: I, and I think most of the attendees, were surprised at how prevalent silent cerebral lesions were in patients with A-Fib, and how A-Fib patients have significantly worse cognitive performance. This is yet another reason not to leave patients in A-Fib, and for those of us with A-Fib to get treatment and/or an ablation as reasonably soon as possible.
S100B testing seems a great way to test for brain damage
S100B testing seems a great way to test for brain damage
S100B Testing: S100B testing seems a great way to test for brain damage after an ablation. Most centers (and insurance companies in the US) won’t routinely do an MRI after an ablation. But an S100B plasma test is more easily and cheaply performed, and may be more accurate than an MRI. But then the question for doctors and patients is what should be done if a S100B test comes out positive? If there are no brain damage symptoms, how concerned should we be?
Last updated: Friday, November 25, 2016
- Gaita, F et al. Prevalence of Silent Cerebral Ischemia in Paroxysmal and Persistent Atrial Fibrillation and Correlation With Cognitive Function. Am Coll Cardiol 2013:62; 1990-7.↵
- Vermeer, SE et al. N Engl J Med 2003;348:1215-22.↵
- Gaita, F et al. Prevalence of Silent Cerebral Ischemia in Paroxysmal and Persistent Atrial Fibrillation and Correlation With Cognitive Function. Am Coll Cardiol 2013:62; 1990-7.↵
20th Annual AF Symposium
by Steve S. Ryan, PhD
This overview should give you a sense of the topics floating through the three days in Orlando and the over sixty presentations by fifty A-Fib experts and researchers. (Most recent brief reports listed first)
(Please be advised that the Symposium organizers go to great lengths not to identify or unfairly publicize one device over another. When writing these reports I often have to do a good deal of research to correctly identify and describe particular devices that are demonstrated, as a service to readers. But this in no way implies or suggests that one device is superior to another.)
Dr. Gerhard Hindricks of the University of Leipzig in Germany gave a dynamic presentation of a catheter ablation of a 46-year-old female with paroxysmal A-Fib using the Rhythmia 3-dimensional multipolar mapping system by Boston Scientific. Along with his colleagues Drs. Andreas Bollmann and Jedrzej Kosiuk, they used the Rhythmia special basket catheter to generate a 3-D map of electrogram voltages and activation times. To me it seemed amazingly fast. The eight-splined bidirectional catheter produced 1,000 data points per minute. In what seemed like only a few passes, they produced a 3-D color reconstruction of the patient’s left atrium.
The actual ablation was routine. They terminated the A-Fib into sinus rhythm without having to use Electrocardioversion. But they found that the PV isolation was incomplete. Using the same Rhythmia 3-D mapping catheter, they were easily and quickly able to locate the gap in the Left Superior PV and ablate it.
Dr. Vivek Reddy from Mount Sinai School of Medicine in New York City gave a very well referenced and persuasive presentation on the Watchman device which closes off the Left Atrial Appendage to prevent clots and strokes. The theory behind the Watchman device is that most A-Fib clots originate in the Left Atrial Appendage (LAA). The Watchman closes off the LAA where 90-95% of A-Fib strokes come from. It’s a very low risk procedure that takes as little as 20 minutes to install. Afterward, you would usually not need to be on blood thinners. (For more, see my article, The Watchman Device: The Alternative to Blood Thinners).
Dr. Reddy certainly persuaded me that the FDA should approve the Watchman device. Dr. Reddy, earlier in Washington, had made the same persuasive arguments before the FDA.
Dr. Andrew Farb from the FDA took the bull by the horns and gave his perspective on the various LAA Closure (Occlusion) Devices. But as one would expect, he didn’t indicate how the FDA would rule on the Watchman device, since deliberations were still ongoing.
After his presentation, I asked him several pointed questions about this, but he was, of course, careful not to comment about current FDA deliberations. My guess? If body language, momentum, mood of the presentations, and more importantly recent research indicate anything, the Watchman device probably will not be approved by the FDA.
There was a palpable sense of sadness at the end of these presentations. The attendees realized that the game may be over for the Watchman device. I hope I am wrong, since the Watchman device would be an important tool to help A-Fib patients. Once the FDA rules and the current clinical trials of the Watchman device end, you will probably have to go to Canada or overseas to get a Watchman device installed.
(Happily I was wrong on this prediction. Update: The U.S. Food and Drug Administration (FDA) approved Boston Scientific’s WATCHMAN™ LAA closure technology for use in the U.S. on March 13, 2015. It has been available internationally since 2009. The FDA approval of the WATCHMAN device is based on the clinical program which consists of numerous studies, with more than 2,400 patients and nearly 6,000 patient-years of follow-up. The Watchman device will be available first at U.S. centers where it has been used in clinical studies.)
Watchman May Win FDA Approval
In my earlier brief reports on the Orlando AF Symposium, based on the recent research and the FDA presentation, I said the Watchman device probably won’t be approved in the US. I’m happy to say that I am most likely wrong.
At the LAA Symposium 2015 in Marina del Rey, CA, it was suggested that the Watchman device may be approved by the middle of this year. One presenter described how the FDA chairman talked with several people who were going to Canada to have the Watchman device installed. He seemed embarrassed that the Watchman was available everywhere in the world but not in the US and said that it has to be approved.
Other doctors I talked with at the LAA Symposium were of the same opinion. Presenters described how clinical trials for other LAA closure devices were on hold so that they could get approved in comparison to the Watchman (Non-Inferiority Trials). Dr. Dhanunjaya Lakkireddy of the University of Kansas Medical Center said that we are at a “tipping point” for the (A-Fib) industry.
As everyone, including the FDA, is well aware, A-Fib innovations usually start in Europe where they are more easily approved. Then only later do they move to the US for FDA approval, since the FDA generally requires more data than European regulators.
Drs. Jun Dong and Andrew Farb from the FDA described the FDA’s ‘Easy Feasibility Study’ (EFS) program where medical device innovations could be evaluated in the US without having to go to Europe first. He encouraged researchers and attendees to take advantage of the new EFS program. This is major news and may make the development of A-Fib innovations much easier to accomplish in the US.
For further information, contact: Andrew Farb, Email: Andrew.email@example.com. 301-796-6317
Dr. Luigi Di Biase from the Albert Einstein College of Medicine in the Bronx, NY and Dr. Daniel Singer from Massachusetts General Hospital in Boston each described potentially great developments in reversal agents for apixaban (Eliquis) and rivaroxaban (Xarelto).
Dr. Di Biase described studies where leaving people on uninterrupted rivaroxaban and apixaban before, during and after an ablation dramatically reduced the amount of silent thromboembolic lesions and were as safe as warfarin with regards to stroke and TIAs. (This didn’t work with dabigatran [Pradaxa].) But if patients develop bleeding or effusion during the ablation, they are in trouble because there is no direct reversal agent as there is for warfarin. He has used Factor IV as an indirect reversal agent. Dr. Singer also described how Factor IV was used as a reversal agent for apixaban.
But there are new reversal agents for apixaban and rivaroxaban which promise to completely reverse the effects of these two drugs in less than four minutes. The FDA is speeding up studies on these reversal agents. But one never knows when or if the FDA will approve them.
Dr. John Day of the Intermountain Heart Institute in Murray, UT (and recently elected president of the Heart Rhythm Society) may be the first A-Fib leader to publicly question whether women should be given one point on the stroke risk CHA2DS2-VASc scale just because of their gender. Many doctors have said this in a circumspect way. Dr. Eric Prystowsky in a presentation at last year’s AHS meeting thought that most doctors would agree with Dr. Day, “as long as there wasn’t a camera focused on them.” He gave the example of a 45-year-old woman in good health and a 45-year-old man with hypertension who according to current guidelines should both be given one point on the stroke risk CHA2DS2-VASc score.
As readers of A-Fib.com, you know that’s been my opinion ever since the original European guidelines came out. Women in their child-bearing years are much less at risk of stroke because of the blood-thinning effect of losing blood each month. And even after menopause women have less risk of stroke. But eventually they do have more strokes. But not because of an innate inferiority, but because women live longer than men. Stroke is age related. An observational Danish registry study documents this.
For more, see The Denmark Study: Women in A-Fib Not at Greater Risk of Stroke Contrary to CHA2DS2-VASc Guidelines!) (Be advised that the original European guidelines were written by doctors with major conflicts of interest.) These guidelines may be a not so very subtle form of gender bias.
Living in A-Fib is more dangerous than having an ablation, according to Dr. Josef Kautzner from Prague, the Czech Republic. Studies have documented that the adverse effects of living in A-Fib, having to take A-Fib drugs and anticoagulants for life are both pragmatically and statistically worse than having an ablation. Dr. Kautzner discussed how A-Fib can cause or is associated with silent brain lesions and dementia. Any time you go into a hospital is a risk. And no one would say that a catheter ablation is a walk in the park. But an ablation is a low risk procedure, though not risk free. The risk is similar to having your tubes tied. The possible adverse effects of an ablation procedure (like bleeding at the groin) are generally temporary, unlike the lasting, permanent damage you can do to your heart, body and brain by living in A-Fib for years.
The most hotly discussed topic at this year’s symposium was rotors. The opinions expressed about rotors were at times very heated, more than I had ever seen at an AF Symposium. Dr. Shih-Ann Chen of Taipei, Taiwan disagreed with Dr. Sanjiv Narayan of Stanford, CA about the basic concepts of rotors and how they should be defined. Dr. Ravi Mandapati of UCLA and Loma Linda University disagreed with Dr. Narayan which was all the more striking in that he had worked with Dr. Narayan when he was at UCLA. Dr. Pierre Jais of Bordeaux, France said that the FIRM mapping system misses 40% of the atrium area.
Drs. Haissaguerre and Jais from Bordeaux and Dr. Sebastien Knecht of Brussels, Belgium gave presentations on how they were using the CardioInsight body surface mapping vest to perform ablations of “drivers” at many different centers, while Dr. Karl-Heinz Kuck from Hamburg, Germany using a different body surface mapping system said that he couldn’t ablate rotors. Dr. Narayan says the FIRM system finds a maximum of 2-3 rotors in the atria, while other systems find as many as seven. The FIRM system says rotors are usually relatively stable and can last as long as 30 seconds while others say they rotate in one fixed spot for only one or two rotations, that they tend to migrate within a certain area.
The presenters obviously didn’t share a consensus of basic concepts of what rotors are, how they work, their importance in A-Fib, how they should be correctly identified, used, and ablated. (It seems to me the Bordeaux group has the best understanding and pragmatic use of rotors. They refer to “rotors” and focal sources as “drivers.”) But the CardioInsight system Bordeaux uses isn’t currently available or isn’t being tested in the US.
Obesity was one of the most often discussed topics. There is a growing consensus among EPs that it isn’t enough to just give obese patients a catheter ablation while not dealing with their obesity. If the obesity isn’t dealt with, their A-Fib is very likely to re-occur. A-Fib will develop in other spots that haven’t been ablated. The condition (obesity) that triggered or caused the A-Fib will trigger or cause it again, if it isn’t taken care of.
Dr. Prashanthan Sanders of Adelaide, Australia described the great results he is getting in his clinic which includes a weight loss program and counseling. He convinces his overweight patients to buy into the program, lose weight, and keep it off. The program works so well that just by losing weight patients become A-Fib free. This program is a holistic approach to health and also is developed to work for diabetes, sleep apnea, hypertension, binge drinking and smoking.
Dr. Sanders foresees a world where some patients become A-Fib free simply by changing their life style, where they don’t have to have a catheter ablation to become A-Fib free.
Many other doctors commented that A-Fib treatment at many centers today includes or should include much more than A-Fib ablation and drugs. A-Fib centers should have nutritionists, exercise therapists, sleep apnea specialists, etc. as part of their A-Fib program.
Dr. John Day of the Intermountain Heart Institute in the Challenging Cases Discussion described his experience with the dreaded Atrial Esophageal Fistula. Though very rare, this is one of the few possible complications of a catheter ablation that can kill you. An ablation, if not done with caution, can irritate and damage the esophagus which often lies right next to the heart. Over 2-3 weeks stomach acid can eat through this damaged area to produce a hole or fistula from the esophagus into the heart.
As soon as Dr. Day saw this patient, he knew it was a fistula and immediately called surgeons and a GI doctor. All the surgeons were doing operations and didn’t want to do the surgery in the EP lab. Dr. Day described how he and his colleagues ran down the hospital hallway to the operating room while giving the patient a transfusion and at the same time pumping out the blood escaping from his heart.
The GI doctor got there first and put in a stent in the esophagus to plug the hole. There was lots of discussion as to whether this was the best approach, but it worked. The patient survived but had to spend a month in the hospital.
This cautionary and very dramatic tale certainly got the attention of all the attendees. No matter how rare a fistula is, every EP and A-Fib center must have an established protocol in place to deal with it. I remember Dr. Hugh Calkins in a previous Symposium advising, “There are only two kinds of EPs—those who have not had an Atrial Esophageal Fistula and those who have!” (Dr. Calkins’ patient with fistula also survived.)
Dr. Peter Kowey of Lankenau Hospital in Winnewood, PA described a case that illustrates the kind of dilemma both doctors and patients often have to face. A 92-year-old woman with paroxysmal A-Fib who had been treated for many years with warfarin had some bruising and nuisance bleeding, but never anything major.
Dr. Kowey thought that ethically he should tell her about the different new anticoagulants which may be superior to warfarin, then see if she wanted to change. She went with apixaban (Eliquis), then six months later had a stroke even though she was taking apixaban properly and conscientiously. Happily, she made an almost full recovery. She returned to warfarin which had worked for her in the past and which she was comfortable using.
One of the reasons Dr. Kowey discussed the new anticoagulants with his 92-year-old patient was because warfarin is considered more apt to cause bleeding in older patients. The newer anticoagulants in clinical trials caused less bleeding. But we don’t have much data from the clinical trials on people over 90 years old.
Can we say that apixaban didn’t work or was ineffective? No. Anticoagulants reduce but do not totally eliminate the risk of an A-Fib stroke. Just because she had a stroke doesn’t mean apixaban didn’t work.
Dr. Jeremy Ruskin pointed out that there has never been and probably never will be a head-to-head comparison of the three new anticoagulants. But in my opinion apixaban (Eliquis) appears to have tested better and is safer than the others
For more, see my 2013 BAFS articles, The New Anticoagulants (NOACs) and Warfarin vs. Pradaxa and the Other New Anticoagulants.
In the satellite case live presentations, Drs. Rodney Horton and Amin Al-Ahmad from the Texas Cardiac Arrhythmia Institute in Austin, TX surprised us by doing an ablation without wearing the standard lead aprons to prevent fluoroscopy exposure. Even more surprising was one of the lab assistants who was pregnant. She could work on the ablation because no fluoroscopy was used. The doctors did the whole ablation using ICE (Intracardiac Echo) and 3D mapping. They showed for example how ICE can be used to thread the catheter up into the heart and into the left atrium. Dr. Horton said that not having to wear those heavy lead aprons would probably add 5-10 years to his ablation career.
(They didn’t wear surgical masks during the ablation which was surprising to me. I will write them for an explanation.)
The live satellite case from Beijing, China was technically flawless and probably a first of its kind. But it wasn’t much of a learning experience for the attendees. The Chinese EPs only used one catheter and had to frequently pull out the mapping catheter and replace it with the ablation catheter, etc. When the expert panel asked them questions, the Chinese EPs either didn’t understand or simply didn’t answer them. They seemed very uncomfortable. It seemed like a throwback to ablation techniques of 20 years ago.
Drs. Claudio Tondo, Gaetano Fassini, Massimo Moltrasio, and Antonio Dello Russo from Milan, Italy showed how they do a catheter ablation for A-Fib and install the Watchman device in the same procedure, when it’s needed. They do the ablation procedure first. Then when the patient is in sinus rhythm, they install the Watchman device. (This can’t be done in the US, because the Watchman device hasn’t received FDA approval. In later discussions including representatives of the FDA, there was an all too real possibility that the Watchman will never receive FDA approval.)
Drs. Kevin Heist and Moussa Mansour from Massachusetts General in Boston showed in a live case how they used a Contact Force Sensing catheter combined with Jet Ventilation. (There are two Contact Force Sensing catheters approved by the FDA—the ThermoCool Smart Touch device by Biosense Webster (approved Feb. 24, 2014) and the TactiCath Quartz Contact Force Ablation Catheter by St. Jude Medical (approved Oct. 27, 2014). This live case used the TactiCath catheter but didn’t imply or suggest it is superior to the ThermoCool catheter. For a description of each, see my 2014 AF Symposium report The New Era of Catheter Ablation Technology: Force Sensing Catheters.
This combination of Force Sensing Catheter with Jet Ventilation for RF ablation probably represents the most advanced RF ablation strategy available today. Jet Ventilation doesn’t stop the heart from beating as in bypass surgery. But to this observer it seemed to put the heart in a type of slow motion with a lot less movement than when the heart is beating in normal sinus rhythm. You could really see a difference when they turned the Jet Ventilation off and on. Slowing down the heart like this helps the ablation doctor make lesions in hard-to-access areas and makes it easier to hold the catheter steady and apply the right contact pressure.
Drs. Michel Haissaguerre and Pierre Jais from Bordeaux/LYRIC gave presentations on the ECGI system. The day before their ablation, the patient lies down on his/her back and a technician places a vest-like device with 256 electrodes over his/her chest and stomach. These electrodes combine with rapid CT (Computed Tomography) scans to produce a very detailed 3D color map of the heart. (For a detailed description and discussion of the ECGI system, see 2013 BAFS: Non-Invasive Electrocardiographic Imaging [ECG]) The system automatically detects rotors and foci and computes them into a “Cumulative Map” or movie. These driver regions are ranked, based on statistical prevalence.
Then, Dr. Sebastien Knecht from CHU Brugmann, Brussels, Belgium, described the AFACART trial design and preliminary results using the CardioInsight ECGI system. Many centers in Europe including four in Germany are now using the CardioInsight. Requiring very little training, technicians and EPs using the CardioInsight system are getting similar great results like the Bordeaux group. Though these studies just started, it looks like the CardioInsight ECGI mapping and ablation system is poised to revolutionize the way EPs map and perform ablations.
Dr. Jose Jalife of the University of Michigan in Ann Arbor, MI, continued his exciting research on fibrosis and A-Fib. In previous Symposiums Dr. Jalife demonstrated how A-Fib produces fibrosis. When he paced sheep into A-Fib, their hearts became fibrotic within a very short time. The markers of fibrosis (collagen and scarring) increased progressively as the sheep went from paroxysmal to persistent A-Fib. (See A-Fib Produces Fibrosis—Experimental and Real-World Data.)
Fibrosis is tissue that has fiber-like characteristics which develop in place of the normal smooth walls of the heart. Fibrotic tissue is scarred, immobile, basically dead tissue with reduced or no blood flow and no transport function. It results in a loss of atrial muscle mass. Over time it makes the heart stiff, less flexible and weak, overworks the heart, reduces pumping efficiency and leads to other heart problems. Fibrosis, up to now, was considered permanent and irreversible. But Dr. Jalife gave his sheep a Gal-3 inhibitor GM-CT-01 that actually prevented and reduced fibrosis! (For his previous presentations, see 2014 BAFS: The Holy Grail: Preventing A-Fib by a GAL-3 Inhibitor.)
In his continuing studies of sheep, Dr. Jalife found that fibrosis predicts recurrence, and that fibrosis can not be reversed if it is well established, even with GAL-3 Inhibitors.
Last updated: Friday, November 18, 2016
A-Fib-Free After Catheter Ablation, Patient on Anticoagulation Therapy for 10 years Develops Cerebral Microbleeds and Associated Early Dementia.
By Steve S. Ryan, Updated March 2016
Dr. John Day, in an editorial in The Journal of Innovations in Cardiac Rhythm Management, described his patient, Bob, who had been on anticoagulation therapy for 10 years, even though he had had a successful catheter ablation and was A-Fib free. Of concern, these new guidelines call for many more people to be on anticoagulant therapy, particularly women.
Of concern, these new guidelines call for many more people to be on anticoagulant therapy, particularly women.
Bob was suffering from early dementia. A cranial MRI revealed many cerebral microbleeds, probably caused by taking anticoagulants for years. Both antiplatelet and anticoagulant therapy significantly increase the risk of cerebral microbleeds which are associated with dementia. These microbleeds are usually permanent and irreversible.
Dr. Day asked, “Could it be that this was an iatrogenic (caused by a doctor’s activity or therapy) case of dementia? Was his 10 years of anticoagulant use for atrial fibrillation the cause of his dementia?”
The New CHA2DS2-VASc Guidelines for Anticoagulation Therapy
Dr. Day discusses the new CHA2DS2-VASc guidelines for anticoagulation therapy. He points out that none of the major studies supporting the CHA2DS2-VASc guidelines have reported the accompanying cerebral microbleed risk. He also calls our attention to the reports from many centers that long-term stroke risk following catheter ablation is very low. Ablation may reduce the total arrhythmia burden or convert recurrences to more organized rhythms, such as an atrial tachycardia, with a lower stroke risk.
This effect of A-Fib ablation isn’t recognized in the latest guidelines.
So, the question is, ‘Why the risks of life-long anticoagulation therapy if the patient has had a successful ablation procedure?’
(See more research contradicting the 2014 Guides: A study using the Taiwan Research Database of 186,570 A-Fib patients, they discounted female gender and only looked at females with a CHA2DS2-VASc score of 2 (one additional risk factor besides being female).1,2,3
Warning: The Risks of Life-long Anticoagulation Therapy
Dr. Day concludes, “Somehow I think we have lost sight of the total picture with the new A-Fib management guidelines. In my mind, I am not convinced that the long-term stroke risk of a CHA2DS2-VASc score of 1 or 2 (depending on which risk factors are present) justifies all of the risks of life-long anticoagulation therapy, particularly if the patient has had a successful ablation procedure.”4 Dr. John Mandrola echoes Dr. Day, “And if there is no A-Fib, there is no benefit from anticoagulation.”5 Anticoagulants are not like taking vitamins, “Oral anticoagulants are high-risk medications.”6
“But CHA2D2-VASc are just guidelines, aren’t they? Doctors don’t have to follow them, do they?”
Unfortunately once guidelines like these become official, they in effect become the law of the land. If a doctor doesn’t follow them and a patient has a stroke, the doctor is almost guaranteed a losing malpractice law suit. The first thing a trial lawyer will point out to an arbitrator or jury is that the doctor didn’t follow current guidelines.
This puts doctors in a very difficult position. Even though Dr. Day knows all too well and agonizes over the fact that his anticoagulant therapy probably caused his patient Bob’s dementia, he can’t change the guidelines.
See also my articles: Women in A-Fib Not at Greater Risk of Stroke! and Israeli Study-Being Female Not a Risk Factor for Stroke.)
Return to Index of Articles: Research and Innovations
Last updated: Saturday, December 31, 2016
- Chao TF, et al. Should atrial fibrillation patients with 1 additional risk factor of the CHA2DS2-VASc score (beyond sex) receive oral anticoagulation? J Am Coll Cardiol. 2015 Feb 24;65(7):635-42. doi: 10.1016/j.jacc.2014.11.046. PubMed PMID: 25677422. http://www.ncbi.nlm.nih.gov/pubmed/25677422↵
- Amson, Yoav et al. Are There Gender-Related Differences In Management, And Outcome Of Patients With Atrial Fibrillation? A Prospective National Study. Arrhythmias and Clinical EP. Acc.15. JACC. March 17, 2015, Volume 65, Issue 10S. doi: 10.1016/S0735-1097(15)60469-7 http://content.onlinejacc.org/article.aspx?articleid=2198096&resultClick=3↵
- Friberg et al. Benefit of anticoagulation unlikely in patients with atrial fibrillation and a CHA2DS2-VASc score of 1. J AM Coll Cardiol. 2015; 65(3):a-232. URL: http://www.sciencedirect.com/science/article/pii/S0735109714070119. doi:10.1016/j.jacc.2014.10.052↵
- Day, John. Letter from the Editor in Chief. The Journal of Innovations in Cardiac Rhythm Management, 5 (2014), A6-A7. Last accessed May 15, 2014, URL: http://www.innovationsincrm.com/cardiac-rhythm-management/2014/may/586-letter-from-the-editor-in-chief↵
- Mandrola, John. Atrial Flutter–15 facts you may want to know. In AF Ablation, Atrial fibrillation. August 5, 2013. http://www.drjohnm.org/2013/08/atrial-flutter-15-facts-you-may-want-to-know↵
- Wilt, Daniel M. and Hansen, Alisyn L. editorial in New Oral Anticoagulants Can Require Careful Dosing Too. Medscape/Reuters Health Information by Scott Baltic, December 29, 2016. http://www.medscape.com/viewarticle/873821?src=wnl_edit_tpal↵
Denmark Study—Being a woman not a risk factor for stroke
The new guidelines for stroke prevention in A-Fib (CHA2DS2-VASc) state that simply being a woman is a risk factor for stroke. But a recent comprehensive study from Denmark indicates this may not be true. (The guidelines were first adopted in Europe in 2012 and in the US in May 2014).
The Danes seem to have an effective health care system for everyone which includes, among other benefits, data on anyone with A-Fib. They looked at 44,744 women with A-Fib. Female gender did not increase the risk of stroke in patients aged less than 75 years. (According to most guidelines, being over 75 years old is a risk factor for stroke irrespective of whether one is female or male.) According to the study’s Dr. Anders Mikkelsen, “This suggests that female sex should not be included as an independent stroke/TE risk factor in guidelines or in risk stratification schemes used in treatment of patients with atrial fibrillation.”
(Added August 31, 2015: An Israeil observational study of 100,000 people came to the same conclusions as the above Denmark study. See Israeli Study—Being Female Not a Risk Factor for Stroke.
Dr. Day—Risks of Life-Long Anticoagulant Therapy
Dr. John Day, in a May 2014 editorial in The Journal of Innovations in Cardiac Rhythm Management, discusses the new CHA2DS2-VASc guidelines for anticoagulation therapy that call for many more people to be on anticoagulant therapy, particularly women. Dr. Day does not go so far as to say the new guidelines are in error (as I do), but he does ask,” What about the 35 year old woman with borderline hypertension and only one A-Fib recurrence each year? Should she now take anticoagulants for the rest of her life even if she has had a successful ablation?”
This editorial was very personal for Dr. Day. One of his patients, after a successful catheter ablation, was on anticoagulant therapy for 10 years and developed early onset dementia. A cranial MRI revealed many cerebral microbleeds. Both antiplatelet and anticoagulant therapy significantly increase the risk of cerebral microbleeds which are associated with dementia. Microbleeds are considered permanent and irreversible.
Dr. Day concludes, “Somehow I think we have lost sight of the total picture with the new A-Fib management guidelines. In my mind, I am not convinced that the long-term stroke risk of a CHA2DS2-VASc score of 1 or 2 (depending on which risk factors are present) justifies all of the risks of life-long anticoagulation therapy, particularly if the patient has had a successful ablation procedure.” For more of Dr. Day’s comments, see The New CHA2DS2-VASc Guidelines and the Risks of Life-Long Anticoagulation Therapy.
Dr. John Mandrola echoes Dr. Day, “And if there is no A-Fib, there is no benefit from anticoagulation.”
Intuitively it doesn’t make sense that simply being a woman makes you more at risk of having an A-Fib stroke. This study seems to confirm what common sense would indicate and is most welcome news for women.
Anticoagulants Not Like Taking Vitamins
Women (and men) should be aware that anticoagulants increase the risk of bleeding disorders* and should be given only to patients at a real risk of stroke. “In addition to bleeding, Pradaxa can cause stomach upset or burning, and stomach pain.” (Pradaxa Fact Sheet PX81802) (These statements don’t capture the actual human toll—burning throat, roiling intestines, diarrhea, burning anus, lasting intestinal damage, etc. that Pradaxa can produce in some people.) According to Dr. David Graham of the FDA, the anticoagulant “Coumadin provides a benefit, but it is also responsible for probably more deaths than any single drug currently marketed.”
Many people have problems when taking anticoagulants and would prefer not to have to take them. One bruises easily, cuts take a long time to stop bleeding, one can’t participate in any contact sports or any activities like mountain climbing, bike riding, etc. If in an accident, one risks bleeding to death, because there is currently no practical way to reverse the anticlotting effect of the newer anticoagulants. When taking anticoagulants, there is an increased risk of developing an hemorrhagic stroke and gastrointestinal bleeding. And anticoagulants often have other bad side effects, make one feel sick, and diminish one’s quality of life.
TV Ads for Anticoagulants
But recent advertising campaigns give the impression that you must take anticoagulants if you have A-Fib, that anticoagulants are the be-all and end-all for treating A-Fib, that if you take anticoagulants, then you will live happily ever after. (Actually anticoagulants are not a treatment for A-Fib, but for the risk of an A-Fib stroke). However, no matter how altruistic these national campaigns sound in trying to increase people’s awareness and knowledge of A-Fib, be advised that their primary purpose is to sell pharmaceuticals.
Gender Bias to Sell More Anticoagulants
If someone tells you that you must take anticoagulants because you are a woman, it may be time to get a second opinion. Don’t let a form of gender bias intimidate you into taking anticoagulants.
Realize also that adding a point to a person’s risk score translates into a huge increase in sales for pharmaceutical companies. The guidelines were written by doctors with major conflicts of interest.
However, if you know the risks and bad side effects of taking anticoagulants but still want to take them, that is certainly an option to discuss with your doctor.
(Thanks to David C. Holzman for calling our attention to this important study for women.)
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