There’s a growing body of evidence linking atrial fibrillation with early onset of dementia, one of the most feared diseases. (New cases of dementia are diagnosed every four seconds.)
When 65+ year olds were asked what disease or condition they were most afraid of getting, 56 percent cited the memory-robbing dementia.
While both Atrial fibrillation and dementia have been linked to aging, neither is a normal part of growing older.
A-Fib Patients: Reducing Your Risk of Developing Dementia
You CAN impact developing or avoiding dementia. Review these articles to learn more about the link between Atrial Fibrillation and dementia:
1. FAQ: “I’m scared of getting dementia. Can the right minerals help? I’ve read about the link with A-Fib. What does research reveal about this risk?”
2. Leaving Patients in A-Fib Doubles Risk of Dementia—The Case for Catheter Ablation
4. FAQ: I’m concerned because Vitamin D deficiency has been tied to both A-Fib and Dementia. What is a normal level of Vitamin D?
5. Risks of Life-Long Anticoagulation Therapy: Patient on Anticoagulation Therapy for 10 years Develops Cerebral Microbleeds and Associated Early Dementia
Strategies for Preventing Dementia
What doesn’t work: current drugs, even statins, don’t work or have mixed results in preventing dementia.
What does work: Catheter ablation to eliminate your Atrial Fibrillation. Patients who get a catheter ablation have long-term rates of dementia similar to people without A-Fib. (This result holds regardless of their initial CHADS2 score.)
Don’t Settle. Seek your A-Fib cure: To decrease your increased risk of dementia, your goal should be to get your A-Fib fixed and get your heart beating normally again. We can’t say it enough:
Do not settle for a lifetime on meds. Seek your A-Fib cure.
Atrial Fibrillation (A-Fib) has been suggested as a risk factor for dementia since A-Fib can lead to a decrease of blood supply to the brain independent of stroke.
Other long-term studies evaluating the link between A-Fib and dementia have shown inconsistent results.
Study Patients and Method
In a 20-year observational study of participants in the long-term Rotterdam Study, researchers tracked 6,514 dementia-free people. Researchers were monitoring participants for dementia and Atrial Fibrillation (A-Fib).
“The Rotterdam Study” is a long-term study started in 1990 in Rotterdam, The Netherlands. Cardiovascular disease is just one of several targeted diseases. Since 2008 it has 14,926 participants.
At the start of the study (baseline), 318 participants (4.9%) already had A-Fib.
During the course of the 20-year study, among 6,196 people without established A-Fib:
• 723 participants (11.7%) developed A-Fib, and
• 932 participants (15.0%) developed incident dementia.
• Development of A-Fib was associated with an increased risk of dementia in younger people (<67 years old).
• Dementia risk was strongly associated with younger people (<67 years old) who developed A-Fib but not strongly associated in the elder participants who developed A-Fib.
The authors concluded… Continue reading
Long-term exposure to warfarin and aspirin, if not well controlled, may result in micro bleeds in the brain that accumulate over time raising the risk of dementia, according to Dr. T Jared Bunch of the Intermountain Medical Center, Murray, UT.
Research Findings: Taking Both Warfarin and Aspirin
Speaking at the American Heart Association’s Scientific Sessions 2014, Dr. Bunch described recent research findings on the incidence of dementia in A-Fib patients taking both warfarin (anticoagulant) and aspirin (antiplatelet).
For 10 years, investigators followed 1,031 A-Fib patients with no previous history of stroke or dementia who were taking both warfarin and aspirin (or clopidogrel).
The data focused on A-Fib patients with abnormally slow clotting times, i.e., INR above 3. (These patients were considered to be receiving too much blood thinning medication.)
Patients with frequently elevated INR occurring:
• 25% or more of the time, were more than twice as likely to develop dementia (5.8%).
• 10% –24% of the time, had an incidence of dementia of 4.1%.
• less than 10% of the time had a risk of dementia of 2.7%.
For A-Fib patients taking both warfarin and aspirin, frequent abnormally slow clotting times (an INR score above 3) had a cumulative effect making them more prone to developing dementia.
Previous Research on Warfarin and Dementia
Earlier research found that patients taking warfarin were more likely to develop dementia if their clotting times frequently were too slow or too fast (i.e., an INR above 3 or below 2).
For these A-Fib patients, over-anticoagulation and under-anticoagulation lead to cerebral microbleeds and clots in the brain, important in the development of dementia.
Dr. John Day, a colleague of Dr. Bunch, describes the tragic case of one of his patients who was on warfarin for 10 years and developed cerebral microbleeds and dementia. Read the article.
What The Research Means to A-Fib Patients
According to Dr. Bunch, with warfarin, “it’s very common to have INR outside the ideal range up to 40% of the time, and over the years there may be an accumulative negative impact on cognitive ability.”
Both studies found A-Fib patients on warfarin to be at greater risk of developing dementia. The more recent study found the risk of dementia was greater when taking both warfarin and aspirin, than the risk of dementia when taking warfarin alone.
If you have to take warfarin, don’t start taking aspirin on your own (because you’ve read it’s good for your heart or may reduce cancer risk.) You may be raising your risk of developing dementia.
On Warfarin? How to Reduce the Risk of Dementia
If you are on warfarin because of A-Fib and also have to take aspirin (or clopidogrel) for example because you have a stent, you could be more than twice as likely to develop dementia.
In this case, you probably can’t stop taking aspirin, but there are ways to no longer have to take warfarin.
• A successful catheter ablation for A-Fib reduces your risk of stroke to that of a normal person. (See my post Catheter Ablation Reduces Stroke Risk Even for Higher Risk Patients.)
• You can have your Left Atrial Appendage (LAA) closed off or removed by devices like the Watchman, Lariat II, or surgery with the AtriClip. (Note: 90%-95% of A-Fib clots come from the LAA).
• Consider switching from warfarin to one of the newer anticoagulants such as Eliquis; (But the NOACs are so new, and since they also work by causing bleeding, this strategy may not work. We don’t know if over time they will or will not have similar effects as warfarin.)
Bottom Line: Do Not Routinely Take Both Warfarin and Aspirin
You can no longer afford to routinely take both warfarin (anticoagulant) and aspirin (antiplatelet)! Talk with your doctor about your increased risk of dementia. (Perhaps take along a copy of this post.)
Don’t make changes on your own: Suddenly stopping daily aspirin therapy could have a rebound effect that may trigger a blood clot. If you have been taking daily aspirin therapy and want to stop, it’s important to talk to your doctor before making any changes.
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.
Dr. Josef Kautzner’s presentation demonstrated that living with “AF is more dangerous than its ablation” because of the risks of cerebral lesions and cognitive impairment. Small cerebral lesions don’t seem to cause symptoms, but obviously doctors want to avoid creating any kind of lesions on the brain if at all possible.
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.
Read my AF Symposium summary on how silent brain lesions develop, and proposed strategies to minimize the risk of silent lesions.
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.↵
FAQs: Mineral Deficiencies & Supplements for a Healthy Heart
A-Fib patients often look for non-drug approaches to ease or prevent the symptoms of their Atrial Fibrillation. Here we share answers to the most often asked questions about minerals deficiencies and the use of supplements.
1. Dementia: “I’m scared of getting dementia. Can the right minerals help? I’ve read about the link with A-Fib. What does research reveal about this risk?”
2. Vitamin D: “How can I tell if I’m lacking in Vitamin D? I’m concerned because Vitamin D deficiency has been tied to both A-Fib and Dementia. What is a normal level of Vitamin D?
3. PVCs and PACs: “I have annoying PVCs and PACs with my A-Fib. Are there natural remedies to reduce these extra beats and palpitations? My doctor says to ignore them.”
4. Nutritional Info: “I tried to talk with my doctor about magnesium and other nutritional supplements. His response was ‘There’s no proof that they work.’ Why are doctors so opposed to nutrition as a way of helping A-Fib.”
Related Question: “What’s the best way to take supplements—at the same time each day or spread throughout the day? In one lot or in divided doses?”
Related Question: “Where can I find reliable, unbiased research and information on specific vitamins and supplements? (I want an independent resource, not some site trying to sell me their products.)”
5. BCAA+G: “The supplement BCAA+G helps builds muscle. Is it a natural remedy that could help my A-Fib? Are A-Fib patients BCAA-deficient?”
7. Chelate: “What does ‘chelate’ or ‘chelated formulas’ mean when talking about vitamin and minerals? Is it important?”
8. Magnesium: “Regarding Magnesium, can supplementing and restoring Mg to healthy levels reverse my A-Fib? I’m about to schedule a catheter ablation. But if supplementing can cure my A-Fib, why do an ablation?”
9. CoQ10 “Can I take the supplement CoQ10 while on Eliquis for Atrial Fibrillation? On your site it says CoQ10 could be helpful. But on my bottle of CoQ10, it says “do not take if you are on blood thinners.”
10. Krill Oil: “I’m interested in the supplement, Krill Oil, that has natural blood thinning properties. I’m taking Eliquis for my risk of A-Fib stroke. Is It OK to take Krill Oil along with Eliquis?”
FAQ Minerals Deficiencies: Vitamin D
2. How can I tell if I’m lacking in Vitamin D? I’m concerned because Vitamin D deficiency has been tied to both A-Fib and Dementia. What is a normal level of Vitamin D?
Vitamin D is important in virtually every tissue and cell in your body. Low blood levels of vitamin D have been associated with increased risk of death from cardiovascular disease, cognitive impairment in older adults and cancer.
The production of vitamin D from the skin decreases with age. In addition, people who have darker skin need more sun exposure to produce adequate amounts of vitamin D, especially during the winter months. Keep in mind that your Vitamin D level in the summer when you get more sun and UVB is probably higher than in the winter.
Testing Options Ask your doctor for a “25-hydroxy Vitamin D Test”. (There is another type of blood test for vitamin D, called a 1,25(OH)₂D test, but the 25(OH)D test is the only one that will tell you whether you’re getting enough vitamin D.)
What Is an Optimal 25(OH)D Level? Vitamin D deficiency is defined as a blood 25(OH)D level below 20 ng/dL. Normal levels are considered to be above 30 ng/dL. (Some sources consider that ‘optimal’ levels are between 50ng/dL–70ng/dL .)
Sun Exposure and Supplements If you tested low, you need to get more sun exposure and/or take a daily supplement (Vitamin D supplementation is safe and inexpensive). For supplement dosage, see Treatments/Mineral Deficiencies.
Monitoring A blood test is recommended to monitor blood levels of 25(OH)D three months after beginning treatment. The dose of vitamin D may need to be adjusted based on these results.
Return to: FAQ Minerals & Supplements
FAQ Minerals & Supplements: Risk of Dementia
1. “I’m scared of getting dementia. Can the right minerals help? I’ve read about the link with A-Fib. What does research reveal about this risk?”
A-Fib and Dementia are two diseases that seem to parallel each other. Like A-Fib, Dementia seems to increase with age, diabetes, hypertension, heart failure, smoking history, and systemic inflammation. Dr. T. Jared Bunch of the Intermountain Medical Center in Utah, identified two other mechanisms of both A-Fib and Dementia: Vitamin D Deficiency and the APOE gene. Both cause less blood to the brain and loss of oxygen, mini clots and vascular problems.
Ablation Decreases Risk of Dementia and Risk of Stroke and Early Death
Several studies showed that people with A-Fib who had an ablation had about the same risk of Dementia (and the same risk of having a stroke) as normal people, while people with A-Fib who didn’t have an ablation had much more risk of developing Dementia (and higher 5 year stroke risk). [Ablation probably increases blood flow to the brain and is responsible for decreasing the risk of Dementia.]
Supplements to Prevent Dementia
Dr. Bunch’s research identified supplements to help prevent Dementia:
• Antioxidant vitamins (E, C, Beta carotene, Flavonoids) They may decrease brain lesions associated with free radical exposure, but evidence is mixed.
• Vitamins B6, B12, Folate, and Vitamin D Vitamin D deficiency tracks with the development of both Dementia and A-Fib, but it’s not yet known if supplementation reduces the risk.
• Omega Fatty Acids/Fish Oil Low intake is associated with Dementia; studies do show the benefit of fish consumption on the risk of Dementia and cognitive decline.
Patients with more active lifestyles have lower risks of Dementia and cognitive decline.
What this means to you: Early intervention, such as A-Fib ablation, proper vitamins and minerals, along with an active lifestyle may improve long-term cognitive outcomes and reduce the risk of Dementia to that of patients with no history of A-Fib.
Return to: FAQ Minerals & Supplements
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↵