Talk:Atrial fibrillation

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Contents 1 What this article needs 2 "Maze" v. "maze" procedure 3 Lone afib 4 Symptoms 5 Electrocardiogram 6 More about classification and treatment 7 External Links 8 Normal vs AFib conduction image 9 Afib vs sinus 10 Thyroxine 11 Over 75 12 Copyediting 13 Organization of treatment section 14 Level 5 headers 15 Sequelae/Natural History 16 Clinical medicine/Template for medical conditions 17 Some sources 18 LIFE EXPECTANCY 19 Assessment 20 Catheter ablation better 21 "Main article: " form needed? 22 Classification 23 Anticoagulation and Lone Atrial Fibrillation (LAF)

[edit] What this article needs

This article needs:

• Some basic electrophysiology - where do action potentials originate, what perpetuates them, what determines whether the impulse is conducted by the AV node.
• A good list of risk factors
• Images of 12-lead ECGs with perhaps an example of PAF or atrial flutter
• Links to international guidelines for treatment, anticoagulation, cardioversion and surgery/EP ablation
• Burden of disease in the Western world, contribution to stroke incidence, perhaps also see if there are studies on the cost of anticoagulation services for AF and whether rhythm control could modify this!
• Is there historical information on the disease entity, eponyms etc.

I'll try to help along on this one! JFW | T@lk 15:34, 21 December 2005 (UTC)

It's a good framework, for sure. There's a lot of jargon and not many references. I think that the causes section needs to be converted into text. Lone AF is absent and more could be said about structural heart disease causing AF. The role of AF in precipitating failure in MS/AS, etc. should also be mentioned. I've been on the cardiac step-down unit the last few weeks (the Smack-down) but should now have some time in the next few weeks to contribute. InvictaHOG 23:36, 26 December 2005 (UTC)

[edit] "Maze" v. "maze" procedure

I left a similar comment on Jamesmcclelland's page. I've lowercased the "maze" in "Cox maze procedure" given that maze is not a proper noun. It would be akin to capitalizing "forceps" in "Debakey forceps" or "clamp" in "Kocher clamp." A casual pubmed search shows that maze is also in lowercase. Andrew73 02:31, 28 December 2005 (UTC)

jamesmcclelland here. It's been used both ways, but it seems that James Cox, who invented the procedure, prefers that "maze" be capitalized to "Maze". I agree that this doesn't make too much sense, but that's how it has usually been done. See his recent publication for instance:

Cox JL. The Role of Surgical Intervention in the Management of Atrial Fibrillation. Tex Heart Inst J. 2004; 31(3): 257–265. PMID 15562846

I left it uncapitalized anyway, rather than go around and around.

Thanks for finding the reference. While Cox may have capitalized "maze" in the original article, the majority of the published literature from what I've seen uses it in the lower case version. It seems that the capitalization is a little bit idiosyncratic, almost an affectation! Andrew73 20:19, 2 January 2006 (UTC)

Actually, I think it's an "attibution" thing; that is, "maze" is relatively generic, whereas "Maze" refers to the procedure he developed. My impression of how the terms are used is that if it's an actual Cox Maze (that is, if Cox was associated with it) - such as the original Cox Maze, the Cox Maze II, the Cox Maze III, or the (can you believe it) Cox Maze IV, it is capitalized. Also, *his* version of the MiniMaze. When others make variations on the theme, such as the various "minimaze" procedures, it is not capitalized. I think that's why you are seeing that much of the literature is uncapitalized.

Here's my position: Cox is indeed the originator of this field of arrhythmia surgery for AF, and I think that it's reasonable to recognize that by things like capitalizing the original Maze(s) as he does. I'd leave other mazes lowercase. This is consistent with the literature in my opinion. What do you think? jamesmcclelland 22:48, 2 January 2006 (UTC)

Interestingly, while "maze" is capitalized in the Texas Heart Journal reference, there are multiple other references authored by Cox where "maze" is left uncapitalized, e.g. PMID 8215657. I'd be curious to hear what others think! Andrew73 22:58, 2 January 2006 (UTC)

We could flip a coin! InvictaHOG 02:31, 3 January 2006 (UTC)

Hmmm... coin flip via internet? The reference you (Andrew73) have cited is from 1993, after his first 75 patients. It was substantially later that other "Maze-like" procedures began to be published and the issue of distinguishing between these procedures became important. jamesmcclelland 04:12, 3 January 2006 (UTC)

Flip the coin here: http://www.random.org/flip.html Now we only have to choose which coin to flip... :) --WS 04:38, 3 January 2006 (UTC)

I will wait a few days and see if anyone else weighs in. jamesmcclelland 07:25, 3 January 2006 (UTC)

I'm having a terrible time convincing people that the procedure was not co-invented by Dr. Maze, and that MAZE is not an acronym for something. Leaving "maze" uncapitalized helps people understand that it's called a Cox maze procedure because it's like a maze.--Mark D Hardy 16:40, 19 May 2006 (UTC)

[edit] Lone afib

I added a little regarding LAF and made some stylistic changes. --DocJohnny 10:19, 30 December 2005 (UTC)

[edit] Symptoms

That AF can be asymptomatic is implied in the text, but I felt it would be better to directly state this as it may not be clear to a lay reader --Mattopaedia 07:42, 31 December 2005 (UTC)

[edit] Electrocardiogram

Is it worthwhile including this image from electrocardiogram (or something like it) to give the reader some instant idea of what is meant by "absence of P waves" etc? --Mattopaedia 07:49, 31 December 2005 (UTC)

I say, be bold and add it! Though it might be better if we duplicated it into several cardiac cycles to show its regularity InvictaHOG 22:55, 2 January 2006 (UTC)

[edit] More about classification and treatment

I have clarified classification based on ACC/AHA guidelines. But more needs to be done to organize the treatment section, especially in regards to initial episode vs. recurrent. I will try to tackle those later. --DocJohnny 17:54, 31 December 2005 (UTC)

Also, I have added references in the forms in in text links, I am unfamiliar with the format used for endnotes. Perhaps a kind bot will assist in formatting. --DocJohnny 13:40, 1 January 2006 (UTC)

[edit] External Links

Hi, I am new to this site but I have found a great website that offers the most in-depth, physician reviewed content on Atrial Fibrillation that I have seen. I tried to add the link but was told it would be removed---and it was. The link to the content is here: http://www.medifocushealth.com/CR004/atrial_fibrillation.php---If you (like me) think its good content, can you tell me how I can add this resource so others may benefit? Thanks.

While the content is of reasonable quality, it is supported with Google ads. Most of the material on the AF page on Medifocushealth should actually already have been incorporated into this Wikipedia article. In that sense, I do not support inclusion of the link.

I see you are alphabetically linking all the pages from that site on Wikipedia. This is spam and I would strongly discourage you from doing this. Wikipedia is not a way to improve site traffic. JFW | T@lk 05:10, 21 December 2006 (UTC)

In the illustration of pathophysiology I believe that the illustration is incorrect in that it shows the wave propagating down the heart. The impluse actually goes down the Bundle of His and then the depolarization of the heart begins the bottom of the heart and works it way up. The squeezing of the heart must begin from the bottom if you think about it as the exit valves are not at the bottom of the heart but roughly in the middle. I would appreciate further commentary from an expert electrophysiologist. Thomas

[edit] Normal vs AFib conduction image

This is in response to a stray post under External Links talk. Under Pathophysiology, the GIF comparing normal conduction v AFib conduction is misleading. This appears to be an artists rendition rather than a medically acurrate and informative image. The conduction goes from the Sinus node to the muscle of the atria to the HIS bundle as shown, but then goes down the Purkinje Fibers down the center of the Ventricular septum. It then activates through the heart muscle from the Apex up to the base of the ventricles. I'll try to find an Image or set of images that would be more accurate.Nbrysiewicz 22:52, 24 March 2007 (UTC)

Here is a GIF of normal sinus rhythm. I don't know how to edit GIFs otherwise I would have made an example of AFib using this GIF. I need help to make this page more accurate. If anyone can, please replace the images with corrected GIFs. http://en.wikipedia.org/wiki/Image:ECG_Principle_fast.gif Nbrysiewicz 00:59, 25 March 2007 (UTC)

[edit] Afib vs sinus

Just looking at the example of supposed Afib I don't know... Without calipers and a longer tracing, it looks more like some kind of block at first glance, the irregularity is too regular. Even if it is Afib it certainly is not a classic looking Afib. I'm going to see if I can find a better one unless someone else can first. - Dan D. Ric 01:30, 25 March 2007 (UTC)

Holy cow. Looking again at the larger image. This is most definitely NOT a tracing of Afib! The r-r intervals, except for the missing beats, are EXACTLY regular. I hope whoever decided this is Afib is never my cardiologist. The image should be removed till a real example of Afib is found. I'd do/say more except it's time for me to go to work. -- Dan D. Ric 01:39, 25 March 2007 (UTC)

The tracing appears to be atrial flutter with variable block. The rate is 150 with occasional dropped beats - the classic rate for atrial flutter is 150. I can convince myself of the sawtooth waveform as well. The morphology of a.fib / a.flutter is different, but the treatment is essentially the same. Dlodge 14:11, 25 March 2007 (UTC)

I'm glad to see someone else looking at this but I don't agree. Having only one lead to look at is a hindrance (as is me being out of practice since I haven't worked in cardiology for 3-4 years) but I'm not sure about a flutter, I don't see the sawtooth. How about some kind of accelerated junctional or junctional tach? Some of those QRS complexes look to have a retrograde P. Whatever it is, it is certainly not a good example of either Afib or flutter. - Dan D. Ric 15:14, 25 March 2007 (UTC)

Certainly a somewhat regular ventricular response. Atrial rhythm is unclear. Either atrial fibrillation with regular noise (electrical or mechanical artifact) or an atypical flutter with noise. I agree that the regular ventricular response makes things confusing. Someone's certainly got a better image, right? Ksheka 13:22, 11 May 2007 (UTC)

[edit] Thyroxine

http://archinte.ama-assn.org/cgi/content/abstract/167/9/928?etoc - thyroxine levels are independently associated with presence of AF, even when asymptomatic and in normal TSH. JFW | T@lk 08:30, 15 May 2007 (UTC)

[edit] Over 75

doi:10.1016/S0140-6736(07)61233-1  - over 75 some are concerned re bleeding risk. This study seems to put that to rest - it compares aspirin to warfarin in a non-randomised fashion (can't randomise for weekly INR checks) and found a 50% relative and 2% absolute risk reduction. JFW | T@lk 09:35, 12 August 2007 (UTC)

[edit] Copyediting

I'm doing a bit of a copyedit to the article. In particular, I'd like to get rid of any headers in level 4 or over (as per the WP:MOS). I've moved some material to relevant sections (e.g. "screening" is now a dedicated section). I've started referencing much content to the ACC/AHA/ESC 2001 guideline. We also have the NICE guideline which definitely needs to be mentioned too. JFW | T@lk 19:17, 29 August 2007 (UTC)

I have been unable to completely eliminate use of level 4 headers. Some more content can probably be referenced to the ACC/AHA/ESC guideline. I will see if I can find this out in due course. JFW | T@lk 22:09, 29 August 2007 (UTC)

[edit] Organization of treatment section

I think the treatment section of the atrial fibrillation might benefit from different organization. What about:

6.1 Rate control versus rhythm control

6.2 Rate control

6.2.1 Acute rate control

6.2.2 Chronic rate control

6.3 Rhythm control

6.3.1 Conversion to sinus rhythm

6.3.2 Maintenance of sinus rhythm

6.3.2.1 Medications

6.3.2.2 Radiofrequency ablation

6.3.2.3 Surgery

With this structure, it reveals that we do not discuss acute therapy and also that we are not distinguishing between conversion to and maintenance of sinus rhythm.Badgettrg 14:58, 6 September 2007 (UTC)

I will agree to any organisation that avoids the need for deep headers. Acute therapy may warrant a separate section (is there any evidence?) but I feel we have quite a lot of information on rate vs rhythm. I thought those agents that converted to sinus also maintained sinus, or am I being ignorant? JFW | T@lk 19:12, 6 September 2007 (UTC)

A little while ago I rearranged the structure of the article to be slightly more straightforward. Today you changed it back without discussion. Why is that? JFW | T@lk 20:46, 6 September 2007 (UTC)

Which part?Badgettrg 20:55, 6 September 2007 (UTC)

I'm mainly referring to the reintroduction of level 5 headers, which I will not support on grounds of readability. I have removed them now, and agree with other modifications you've made. Never mind.

Are you aware of any cultural references and QOL studies in AF? I have identified American Journal of Medicine 2006;119(5):448.e1-448.e19. JFW | T@lk 12:00, 7 September 2007 (UTC)

cultural references and QOL studies in AF -> do not know of any

I still have some trouble with the treatment section. For example, the paragraph 'In refractory cases, where none of the above drugs are sufficient' being in the rate control section and not having a section titled 'Rate control versus rhythm control'. I think you are wanting to organized based on available treatment modalities, whereas I prefer to organize around the clinical settings likely to arise - even though it means discussing a treatment in more than one section.

The pros/cons of level 5 headers is interesting; so the discussion does not get lost, I am continuing it below in its own section.Badgettrg 03:47, 9 September 2007 (UTC)

[edit] Level 5 headers

Personally, I do not mind the version with level 5 headers if there are concepts that really nest that deep. I could not find any WP recommendations against using level 5 headers - though I may have missed something - I checked Wikipedia:Manual of Style (headings). Regardless, in searching for WP policy on this, I found an interesting technical compromise - Help:Section: Limiting the TOC. My reasons for using headers as needed are:

1. A number of times, I have found myself and other authors, putting too much detail about a subtopic in page, not realizing that a page already exists that is devoted to the topic (see cluster of topics on low back pain). This duplication of content then snowballs to where we have two large texts in parallel on the same topic. It is time-consuming and nearly impossible to harmonize and maintain the separate sections.
2. When I have watched students and residents reading Internet pages, I am impressed how often the answer is in front of them but they do not see it - in part because there the blocks of text are too large, or the text they want is not represented in the TOC. Two studies that somewhat support the advantages of sections are Answering physicians' clinical questions: obstacles and potential solutions and Using structured medical information to improve students' problem-solving performance. Unfortunately, these articles do not address how much nesting can occur before text and TOCs become unusable.

Two avoid these two problems, I would use 5 sections if they are needed. However, determining 'need' is difficutl. If your not liking level 5 is the effect on the TOC, what about Help:Section: Limiting the TOC? So we would use {{TOClimit|limit=4}} or even {{TOClimit|limit=3}}. While a second alternative is to use bold text in front of paragraphs, this precludes using tags such as {{main|warfarin}} to visually alert in readers and authors that more detailed content is available.

What about the following which I think avoids level 5 headers. This could be done with {{TOClimit|limit=4}} or even {{TOClimit|limit=3}}:

6.1 Rate control versus rhythm control

6.2 Rate control

6.2.1 Acute rate control

(allows space for discussion that we currently do not have about using beta and ca blockers intravenously)

6.2.2 Chronic rate control

6.3 Rhythm control

6.3.1 Conversion to sinus rhythm

6.3.1.1 Medications

6.3.2.1 DC Cardioversion

6.3.2 Maintenance of sinus rhythm

6.3.2.1 Medications

6.3.2.2 Radiofrequency ablation

6.3.2.3 Surgery

I think this is a difficult topic to organize, yet this page is very good. When I look at UpToDate's content, it is rather disorganized with 21 chapters that have a-fib in the title.Badgettrg 03:47, 9 September 2007 (UTC)

I think I can agree with the outline. An alternative for {{TOClimit}} is using the semicolon method. Prefacing a header with a ";" (instead of surrounding it with "=" signs) generates a bolded heading that doesn't show up in the TOC. JFW | T@lk 20:52, 15 September 2007 (UTC)

For your consideration (From my presentation on the topic a couple months ago):

1. Epidemiology

2. Etiology

3. Classification

4. Sequelae

5. Pathophysiology

6. Mechanism

7. Evaluation

7.1 Minimal evaluation

7.2 Extended evaluation

8. Management

8.1 Anticoagulation

8.2 Rate vs. Rhythm control

8.2.1 Rate control

8.2.2 Cardioversion

8.2.3 Maintenance of sinus rhythm

Ksheka 14:00, 17 September 2007 (UTC)

Okay. I decided to be bold and changed the organization of the entire article based on my outline above. We'll still need 4-level-deep headers, but the organization works better in general. (Though I wasn't sure where to put History. :-)) FYI, I think there is still a lot to be written in many of the sections. Ksheka 02:20, 18 September 2007 (UTC)

[edit] Sequelae/Natural History

For what it's worth, I think we're missing out without a sequelae (or natural history) section of the article. Stroke is one thing to be mentioned. Tachycardia-induced cardiomyopathy is another. And of course death. It's all in the article (somewhat spread out), but casual readers may look for a section like that. Ksheka 12:06, 19 September 2007 (UTC)

[edit] Clinical medicine/Template for medical conditions

1. Going by Template for medical conditions, ok to move Classification to the first section?

Sounds like Classification should go before Diagnosis. Not sure if it should go before Signs and symptoms. First section is certainly reasonable for me. Ksheka 00:42, 20 September 2007 (UTC)

1. Very good point about missing natural history. I think I would label this 'complications' and go after prognosis is the standard order. To me this is so important, we should lobby to get it added to Template for medical conditions so other topics benefit from this structure.
2. Ok if I insert a section 6.6.6 for "Determining risk of stroke"?

Badgettrg 12:59, 19 September 2007 (UTC)

I was thinking of a new 6.0 - Natural history, with stroke being 6.1 and risk of stroke 6.1.1. Ksheka 13:40, 19 September 2007 (UTC)

This brings up a recurring conundrum for me: when a treatment decision is tightly bound to a prognostic calculation, where do you put the prediction rule for the calculation? In the prognosis section, or the treatment section, or the complications section, or the natural hx section? This one stumps me.Badgettrg

Prognosis and natural history generally mean the same thing. I would put risk calculations in with them. That also means putting natural history/prognosis earlier in the article than treatment. (between Pathophysiology and Treatment in the current article) Ksheka 00:39, 20 September 2007 (UTC)

Also, are we so bound by Template for medical conditions, or it just a gentle suggestion? I haven't been too active lately in wikipedia and wasn't sure if this was something that all medical articles were being refactored into. Ksheka 16:24, 19 September 2007 (UTC)

Doubt we are bound, but I do not know. In some ways (having classification early) it helps much, but in others (prognosis/complications) it is not helpful to me in its current form.Badgettrg

There is some flexibility on order. FYI, Wikipedia:Manual of Style (medicine-related articles) has superseded Template for medical conditions, and provides some guidance on these issues, under the header "Diseases/disorders/syndromes". --Arcadian 01:53, 20 September 2007 (UTC)

[edit] Some sources

Prevalence of Diagnosed Atrial Fibrillation in Adults may be a better source for the "2.3 million" statistic. The mortality figure is well supported with PMID 11978585. I will add these sources in due course (i.e. when I've scoured the fulltext). JFW | T@lk 16:47, 24 September 2007 (UTC)

I found this useful. JFW | T@lk 16:49, 24 September 2007 (UTC)

I noticed a lot of references pointing to the guidelines. As you noticed, at least one of the references in the guidelines (to statistics) doesn't make sense. Probably better to cite the actual papers rather than the guidelines, right? Ksheka 19:50, 24 September 2007 (UTC)

I refer to guidelines when there is a cornucopia of papers but little agreement, and where there are various approaches for treatment and priorities are needed. If the guidelines are based on systematic reviews, they are very useful indeed. Now that we have found a rotten apple, a newer reference is obviously needed. JFW | T@lk 21:31, 16 October 2007 (UTC)

[edit] LIFE EXPECTANCY

Could someone add a section to this article about life expectancies for sufferers? Thanks! —Preceding unsigned comment added by 124.171.95.93 (talk) 07:19, 30 September 2007 (UTC)

I'm not quite sure if that data is available. It is going to be a number with a very wide margin of confidence, rendering it practically meaningless. Some people live with AF for decades, and others have recurrent debilitating strokes. JFW | T@lk 21:31, 16 October 2007 (UTC)

[edit] Assessment

I don't usually rate things above "B" for the WPMED project, but it seems to me that this might easily meet the Good Article criteria. Perhaps someone should look up the criteria and see whether it seems likely to survive a nomination. WhatamIdoing (talk) 23:32, 19 January 2008 (UTC)

[edit] Catheter ablation better

http://archinte.ama-assn.org/cgi/content/abstract/168/6/581 catheter ablation (CPVA) is better than rhythm control. JFW | T@lk 02:59, 25 March 2008 (UTC)

[edit] "Main article: " form needed?

After a number of section headings there is a reference to Main article. For example,

    Electrocardiogram
         Main article: Electrocardiogram

    Atrial fibrillation is diagnosed on an electrocardiogram (ECG), an investigation ...

In the above excerpt, "Main article: Electrocardiogram" doesn't seem to be needed since there is a link to the electrocardiogram wiki in that section. Perhaps it should be deleted along with similar instances of "Main article: xxxxxx" in other sections where the link is provided to their respective xxxxxx wikis. I checked that all sections have appropriate links in their respective text. ( I added a link in the one case where there wasn't one in the section's text.) Bob K31416 (talk) 03:24, 19 May 2008 (UTC)

The {{Main}} template should really only be used if it is a subarticle of the present one. JFW | T@lk 05:34, 20 May 2008 (UTC)

JFW, Thanks for the info. After reading your comment and looking at {{Main}} and Wikipedia:Summary style it does appear that the {{Main}} template was inappropriately used since e.g. the article Electrocardiogram did not grow out of the present article Atrial fibrillation. For those interested, this excerpt from Wikipedia:Summary style gives more useful details of the proper use of the {{Main}} template,

"Wikipedia articles tend to grow in a way which lends itself to the natural creation of new articles. The text of any article consists of a sequence of related but distinct subtopics. When there is enough text in a given subtopic to merit its own article, that text can be summarized from the present article and a link provided to the more detailed article."

So I'll delete instances of the form "Main article: xxxxxx" that refer to wikis that were started before the present article and thus weren't originally in the present article. I'll look to see if the other "Main article" references were originally in the present article.

However, even if they originated in the present article, it still doesn't seem useful to use the {{Main}} template if there is a link to the spinoff article in the section's text. I'd appreciate any more of your thoughts. Bob K31416 (talk) 15:10, 20 May 2008 (UTC)

I investigated whether any of the "Main article" references were originally in the present article. I found that almost all of the "Main article: xxxxxx" entries were made on 24Sep2007 by Ksheka. Also, I looked at the first instance of the referenced articles in their respective histories and the corresponding state of the AF article at that time for many of the referenced articles. Most likely all of the referenced articles did not first appear in the present article on AF so, with my previous remarks in mind, there doesn't seem to be any reason for keeping the "Main article: xxxxxx" entries. Bob K31416 (talk) 22:15, 20 May 2008 (UTC)

[edit] Classification

It appears to be difficult to achieve a well organized classification system for AF. This may be due to: the diversity of episode timing and termination characteristics; the diversity of category names and their definitions that have appeared in the literature; and the seemingly inevitable overlap of categories. Even the AHA/ACC/ESC 2006 Guidelines appears to have trouble with coherence in this regard. The part of those Guidelines that seems to have the simplest and most systematic attempt at classification is Fig. 3. From that figure comes the following classification system:

• First detected
• Paroxysmal - self-terminating, lasting less than 7 days
• Persistent - not self-terminating, lasting more than 7 days and terminated by intervention
• Permanent - not self-terminating, lasting continuously long-term (e.g. for a year or more) and termination by intervention either failed or not attempted

Additional categories come from the rest of the Guidelines' classification section:

• LAF
• nonvalvular

Currently, the AF wiki's interpretation of the Guidelines' classification system lumps together most of the major categories (paroxysmal, persistent, and permanent) into the one category "Recurrent atrial fibrillation". Furthermore, "Recurrent..." is too large a category compared to the "First detected..." category. So it seems reasonable to use the system in the Guidelines' Fig. 3 to replace the "Recurrent..." category in the AF wiki with the categories Paroxysmal, Persistent, and Permanent.

Also, in addition to the LAF category in the AF wiki, the category "Nonvalvular AF" should be mentioned in the Classification section since it is referred to later in the AF wiki, it is in the classification section of the Guidelines, and it appears in many other journal articles.

Finally, the use of the term "chronic" can be a source of confusion. It has been used to differentiate long-term episodes from short-term episodes but this can be confusing. The reason for the confusion is that one might reasonably think that the term "chronic" would apply to having short-term episodes frequently, over and over again, without an end to the paroxysmal AF.

Bob K31416 (talk) 01:49, 26 May 2008 (UTC)

[edit] Anticoagulation and Lone Atrial Fibrillation (LAF)

The first line of the section on Anticoagulation is:

“Patients with atrial fibrillation, even lone atrial fibrillation without other evidence of heart disease, are at increased risk of stroke during long term follow up.^[1]”

One has to be careful interpreting the cited reference regarding LAF. It’s not clear that any of the patients who had strokes in the study were in the LAF category just before they had their stroke. In fact, they probably weren’t in the LAF category just before their stroke since on page 3453 of the article was the following statement,

“With total cardiovascular disease developing in more than 40% of the lone AF subjects at risk in this study, one would expect that underlying heart disease was present at the time of AF diagnosis, although clinically not observed nor unexpected in this group of older individuals.”

In other words, 40% of the subjects in the study who were supposedly in the LAF category at the beginning of the study either had or developed cardiovascular disease that moved them out of the LAF category. Furthermore, most if not all of the subjects who had a stroke were probably no longer in the LAF category just before the stroke but were among the 40% who had cardiovascular disease. Support for this assertion is a more current study of LAF which stated,

“Risk for stroke or transient ischemic attack was similar to the expected population risk during the initial 25 years of follow-up but increased thereafter (P=0.004), although CIs were wide. All patients who had a cerebrovascular event had developed > or = 1 risk factor for thromboembolism.”^[2]

Thus, I feel that the phrase "even lone atrial fibrillation without other evidence of heart disease" should be deleted along with its associated reference, and the rest of the sentence should be modified to exclude LAF from the general assertion.

Bob K31416 (talk) 04:19, 4 June 2008 (UTC)