Category Archives: Stroke Prevention

Do NOT Rely on AF Detect Smartphone App To Diagnose Atrial fibrillation

I’m writing this brief post as a warning to any individuals who have purchased the  smartphone app AF Detect (screen shot below from Apple app store.) It is not a reliable detector of atrial fibrillation (AF).

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A patient of mine with AF recently  purchased this app unbeknownst to me. He  relied on its faulty information which  reassured hm he was not in AF when in fact he was in AF. Such misinformation has the potential to lead to dangerous delays in diagnosis.

There are multiple reviews on the Apple and Google app sites which confirm the total lack of reliability of this app to diagnose AF with screen-shot-2017-02-19-at-9-18-10-ammultiple instances of both failure to detect known AF and inappropriate diagnosis of AF when rhythm was not AF.

In the description of the app the company says the app will “transform you rmobile device into a personal heart rate monitor and atrial fibrillation detector”.

However after purchasing the app and before using it you see this disclaimer which img_8348states it is not to be used for any medical diagnosis.

 

 

 

 

 

 

I will be performing a more detailed analysis of this app’s performance in the future and contacting the FDA about the danger such inaccurate medical testing confers on victims.

In the meantime if you have any experience with this app or other apps claiming to detect AF reliably using detection of the pulse from finger application to the camera lens please share them with me (via email  DRP@theskepticalcardiologist.com or via comments below.)

-ACP

Choosing A “Healthy” and “Natural” Snack: Kind Bars Versus Simple Stroke-Busting Nuts

The eternal fiancee’ of the skeptical cardiologist (EFOSC) deserves serious kudos for (among myriad other things) challenging his conventional ideas about heart-healthy food and serving as his dietary muse.

However, the EFOSC seems to have a weakness for what I would consider a highly processed, sugared up, over-priced piece of marketing hype—Kind Bars.

I asked the EFOSC recently why she was so enamored of Kind Bars and she told me “I like that they are convenient, you can find them anywhere, they are not expensive and they taste good and they are low in sugar and they are 100 times better than all the other snack bars on the market that are expensive and have tons of sugar and chemicals and disgusting things in them:

She also points out that for frequent business travelers, the bars are more convenient (and often cheaper) than buying  a bag of nuts in an airport kiosk.

She is not alone.

The Booming “Healthy and Natural” Snack Bar Business

The “healthy” snack bar business has been booming lately.

The WSJ points out

“Bar makers are opening the floodgates on nuts, dried meats, cricket flour and other nutrient and protein-rich ingredients to compete for consumers and command top dollar. Many of these ingredients cost more than those found in a traditional cookie—and as sources of protein, ounce for ounce, some of them cost more than a steak.There are 1,012 nutrition bars on the market now, compared with just 226 a decade ago, according to a tally by Valient Market Research in Philadelphia.”

Consumers, attracted by convenience and a desire for “healthy and natural” food are paying more for snacks like Kind bars which have high profit margins.

“The average bar costs about two dollars, up from just one dollar 10 years ago, a sign of how much more consumers are willing to pay, or “diminishing price sensitivity,” as Valient founder Scott Upham calls it. “The cost of ingredients makes up only 25% of the price, and profit margins for bars tend to hover as high as 40% to 50%, compared with only 20% to 30% for most other packaged foods, says Mr. Upham.”

Stores love them because “they are individually wrapped and have a long shelf life, yet they are popular and turn over fast.”

Are Kind Bars And Their Ilk Healthy?

Interestingly, about a year ago, the FDA issued a “warning letter” to Kind asking the company to remove the term “healthy” from its product labels.

Violation 1a. of that letter fingers Kind Fruit & Nut Almond & Apricot for having 3.5 grams of saturated fat per 40 grams of food (the so-called Reference Amount customarily consumed or RACC) which is more than the 1 gram of saturated fat per RACC allowed if is one is going to describe one’s food as healthy.

This is clearly a ridiculous and out-dated requirement: saturated fats are a diverse category of nutrients, some of which are likely very healthy (see my posts on dairy fat or coconut oil). According to these criteria, foods that are clearly very healthy such as avocados, salmon and nuts, cannot be labeled as healthy.

Kind fought back and challenged the FDA and the FDA backed down.

According to the WSJ:

“The FDA said in a statement to The Wall Street Journal that in light of evolving nutrition research and other forthcoming food-labeling rules, “we believe now is an opportune time to re-evaluate regulations concerning nutrient content claims, generally, including the term ‘healthy.’”

However, I don’t think Kind bars are necessarily a healthy good food choice. I think people buy them because they have been slickly marketed as “healthy” and “natural.”

As Marion Nestle points out, when it comes to food labels, “healthy” and “natural” are marketing terms.  Their purpose is to sell food products.

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Is this the most annoying advertising blather in existence? Is the EFOSC a KINDAHOLIC with an uncontrollable love for KIND and spreading kindness?

The ingredients in the almond and apricot Kind bar are: Almonds, coconut, honeynon GMO glucose, apricots, apple juice, crisp rice, vegetable glycerine, chicory root fiber, soy lecithin, citrus pectin, natural apricot flavor.

Nutrition: 180 calories, 10 g fat (3.5 g saturated fat), 25 mg sodium, 23 g carbs, 3 g fiber, 13 g sugar, 3 g protein

Basically, the healthy part of this Kind Bar is almonds and coconut, which you could purchase for a hell of a lot less than what you are paying for this processed junk.

Also, please note that it doesn’t contain any actual apricots, merely “apricot flavor.”

Also, note that the third ingredient is honey and the fourth is non GMO glucose. What on earth is non GMO glucose? Do we really care whether the added sugar you are pumping into your crappy bars is GMO or non GMO?

Some Kind bars are clearly no healthier than a typical Payday candy bar:

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Is a KIND bar any healthier than these Halloween treats? Is that Jenny in the background, Dr. Pearson’s marvelous medical assistant?

IAs Crains  writes:

“the packaging of the dark chocolate cherry cashew bar advertises the word “Antioxidants.” In other words, the bar isn’t promoted as being low in sugar, so it’s a fair choice to compare with a PayDay.
The Kind bar has 9 grams of fat—1 gram less than PayDay’s bar. The sugar count, at 14 grams, is 2 grams less than PayDay. So far, so good. But this particular Kind product has a total carbohydrate count 1 gram higher than PayDay, and 1 fewer grams of protein. The bar has 2.5 grams of dietary fiber, a fraction more than PayDay.”

The Kind PR machine responds thusly:

“It is not at all a fair comparison to equate KIND’s Dark Chocolate Cherry Cashew bar to a Pay Day,” a company spokesman said. “This completely ignores the nutrient-rich ingredients that are in a KIND bar, not to mention the exponentially lower level of sodium.”

You can buy 24 Payday bars at Sam’s Club for $14, about 61 cents a bar.

To be fair to the EFOSC, she usually only eats Kind bars that have about 5 grams of sugar.

Preventing Stroke and Heart Attack with 30g of “Mixed Nuts” Daily

In a previous post (Nuts, Legumes, Drupes and Mortality)  I summarized the evidence IMG_3593supporting the cardiovascular benefits of consuming various kinds of nuts.

The PREDIMED trial, in particular, showed a remarkable benefit in reducing heart attacks and strokes when patients ate a Mediterranean diet supplemented with 30g mixed nuts per day (15g walnuts, 7.5g almonds and 7.5g hazelnuts). Walnuts and almonds are actually drupes, but hazelnuts are true nuts.

The  Mediterranean diet, including nuts, reduced the risk of cardiovascular diseases (myocardial infarction, stroke or cardiovascular death) by 30% and specifically reduced the risk of stroke by 49% when compared to a reference diet consisting of advice on a low-fat diet (American Heart Association guidelines). The Mediterranean diet enriched with extra-virgin olive oil also reduced the risk of cardiovascular diseases by 30%.

You can buy 454 grams of walnuts or hazelnuts for $14 , and 454 grams of almonds for $10. Thus, for 46 cents for the walnuts, 23 cents for the hazelnuts and 16 cents for the almonds (total 85 cents) you can recreate the snack that the Spaniards ate in PREDIMED.

This compares to Kind bars which retail anywhere from $1.99 to $3.50.

The PREDIMED investigators explain why they chose these specific nuts:

“WALNUTS. Walnuts differ from other nuts in that they are very rich in omega 6 and omega 3 type unsaturated fats. Moreover, the antioxidants they contain are among the most powerful in the plant world. It should be mentioned that, like omega 3 in fish, nut fats possess important beneficial properties for general health and the heart in particular.

ALMONDS. Almonds form part of many traditional desserts and sweets of Arabic origin, such as nougat. Currently, Spain is the second largest producer and consumer of almonds in the world, after the United States. As with hazelnuts and olive oil, almonds are rich in oleic acid. They differ from other nuts in that they contain more fibre, vitamin E, calcium and magnesium.

HAZELNUTS. Hazelnuts, another widely consumed nut in Spain, are very rich in oleic acid. Furthermore, they are nuts that provide a large amount of folic acid, a vitamin very important for regulating the metabolism, a lack of which can lead to thrombosis and an acceleration of degenerative processes such as arteriosclerosis and senile dementia.”

Unfortunately, I can eat neither hazelnuts nor walnuts (tree nut allergy), but I’ve decided to create for my patients little baggies filled with 30 grams of the magical PREDIMED nut mixture. I’ll give these out during office visits as I explain the glories of the Mediterranean diet (I’ll try to forbear elaborating to them the difference between drupes and nuts).

I need a catchy name for these bags-“Pearson’s PREDIMED bags” or “Stroke-busting nuts?”

If any reader or patient has a suggestion, please add it to the comments.

If I choose your suggestion, I’ll provide you with 10 bags of nuts and oodles of glory!

Hopefully, once I start creating the nut bags, the EFOSC will begin to eschew the faux healthiness of Kind bars and embrace the natural and unmarketed goodness of drupes and nuts.

Kindly Yours

-ACP

Somes notes:

A drupe is a type of fruit in which an outer fleshy part surrounds a shell (what we sometimes call a pit) with a seed inside.  Some examples of drupes are peaches, plums, and cherries—but walnuts, almonds, and pecans are also drupes. They’re just drupes in which we eat the seed inside the pit instead of the fruit!

In PREDIMED:

“Every 3 months a supply of 1,350-g walnuts (®California Walnut Commission, Sacramento, Cal), 675-g almonds (®Borges SA, Reus, Spain), and 675 g hazelnuts (®La Morella Nuts, Reus, Spain) is provided to each participant assigned to the MeDiet+Nuts group.”

 

AliveCor Is Now Kardia and It Works Well At Identifying Atrial Fibrillation At Home And In Office

I’ve been using the AliveCor Mobile ECG App/Device to record my patients’ heart rhythm in my office for about 6 months now.

It has for the most part taken the place of the more elaborate, but cumbersome and time-consuming, 12-lead ECG in patients where heart rhythm is my only concern.

I’ve also convinced about a dozen of my patients who have intermitent atrial fibrillation to obtain the device and they are actively using it to monitor at home their heart rhythm. Through the AliveCor website, I can view their recordings and see what their heart rhythm is doing when they have symptoms.

Last week, a patient of mine (I’ll call her Suzy) who has had significant prolonged episodes of atrial fibrillation associated with heart failure (but cannot tell when she is in or out of rhythm) notified me that her device was interpreting her rhythm as atrial fibrillation. She had not had any symptoms, but was making  daily recordings for surveillance.

Suzy called our office and we brought her in the next day and confirmed with a 12-lead ECG that she was indeed in atrial fibrillation with a heart rate of 120 beats per minute.

It’s pretty amazing that this little, inexpensive device can now replace expensive and elaborate long term cardiac monitors for many of my patients.

AliveCor Rebrands Itself to Kardia


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I’ve noticed that AliveCor has rebranded itself as Kardia. If you go to http://www.alivecor.com now you see the fourth generation device along with promotion of a “Kardia band” which apparently works with an Apple Watch to record your ECG.

The Kardia band is not available for purchase at this time but if and when I can get one, it might motivate me to purchase an Apple watch.

When I purchased my AliveCor device in June, 2015 it cost $74.99 from Amazon.com. The newer version is priced at $99 at both AliveCor and Amazon websites. I’m told by Dr. David Albert of AliveCor that this “fourth generation” version is more accurate, so I have purchased it to see if it reduces the problem of occasional bad recordings.

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You can see in this picture from the website that the formerly flat metal electrodes now have bumps. Dr. Albert says these result in more surface area for better contact with skin. We will see.

The Value of Early Detection Of Atrial Fibrillation

Meanwhile, I will be doing an electrical cardioversion (shocking or resetting the heart) on Suzy to get her back to normal sinus rhythm.  If we had not detected the asymptomatic onset of her rapid atrial fibrillation using the AliveCor/Kardia device, chances are we wouldn’t have known about it until her heart muscle weakened again and she became short of breath from heart failure.

I have Suzy on blood thinners to lower her risk of stroke associated with her Afib but for my patients who are not on blood thinners, detection of silent or asymptomatic AFib is even more important.

-Affibly yours,

-ACP

p.s. The skeptician in me feels this post borders on infomercialese.

Let me make it clear that I have no connection with the company formerly known as AliveCor and have received nothing from them (not even free test devices or Apple Watch Kardia Bands!) but I’m just really excited about the device and how it can help my patients (oh, please excuse me, this really sounds like marketing) “empower” themselves to take control of their heart rhythm.

In the course of writing this, I’ve discovered an academic paper evaluating 13 ECG smart phone type ECG devices so there are other devices you could try. I haven’t had the time or resources to evaluate them.

AliveCor Smartphone App Detects Atrial fibrillation: Potential for Stroke Prevention

Atrial fibrillation (AF)  is a common abnormal rhythm of the heart which causes 1 in 4 strokes. Those afflicted with AF may lack any symptoms or only have a vague sense of irregularity of their heartbeat and thus the first symptom of AF can be stroke.

The gold standard for diagnosing AF has long been the electrocardiogram (ECG or EKG) and typically the ECG involves placing 12 electrodes on the chest/arm/legs and recording the electrical activity of the heart on an expensive device.

I’ve been checking out a device made by Alive Cor which works with your smart phone to record a single channel ECG and is capable of accurately diagnosing if you are in the normal (sinus) rhythm or in AF.
Screen Shot 2015-07-12 at 8.45.49 AMYou can purchase the third generation (significantly smaller then earlier versions) AliveCor Mobile ECG from Amazon or from AliveCor directly for 74.99$ and it works with an app with both iOS and Android devices.

I used mine with my iPhone 6. At first I carried it separately, fearing the added bulk when stuck on to my iPhone case but after a while I realized that it was never with me when I wanted to use it and that there was a huge risk of losing it and so I used the backing adhesive to attach it to my case.

After pairing the device with the app you put two fingers on each of the metal pads and the smartphone screen displays the recording. After 30 seconds of recording it then interprets the rhythm.

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Typical recording in normal sinus rhythm. The red arrow indicates the small p waves which are the electrical signal of the upper chambers (the atria) depolarizing , the blue arrow indicates the electrical depolarization of the ventricles (QRS). The orange arrow indicates that the time interval between the QRS complexes is the nearly the same for each beat, indicating the regularity that we expect when in NSR compared to AF.

Above is a typical recording I made in my office on a patient who had a history of AF. The quality is good and I can clearly see that he is in normal sinus rhythm. The app correctly made the diagnosis of NSR and calculated his heart rate at 68 beats per minute.

One day I had most of my patients record their ECG’s using AliveCor and compared it to the standard 12-lead ECG we normally record. The device correctly identified the two patients with AF out of this group and correctly identified the normals.

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AliveCor recording of patient with AF with heart rate of 70 beats per minute. Note the absence of p waves before the QRS complexes and note the beat to beat variation in the RR interval (orange arrow)

This recording is from a patient with persistent AF which had recurred two weeks earlier. The device correctly identified AF.

Studies have documented that AliveCor Mobile ECG can accurately diagnose AF in a screening setting and the FDA approved the device for AF screening in 2014.

Given the high prevalence of silent AF, the strong association of AF with stroke and the availability of anticoagulants which reduce AF associated stroke by 70%, screening for AF with devices like AliveCor holds the promise of preventing large numbers of stroke.

(For my comments on taking the pulse and stroke prevention see here and on the inadvisability of a routine 12-lead ECG see here)

AliveCor allows physicians utilizing the Mobile APP and ECG to have a “dashboard” into which their patients can transmit their AliveCor ECG recordings.

I will be discussing this remarkable new device with my AF patients  who are smartphone enabled. I think it will advance our ability to more efficiently and quickly diagnose AF in them.

My standard approach if a patient with AF calls and says that they feel like they are out of rhythm is to have them come into the office for a full 12-lead ECG. If they are AliveCor enabled, they could make their own recording, and we could review that remotely and make a diagnosis without the office visit.

Let me know your thoughts on smartphone ECGs.

fibrillatorily yours,

-ACP

Why Does The TV Tell Me Xarelto is a BAD DRUG?

One of my patients called the office today concerned about a medication she was taking because she was “seeing about 4-5 commercials a day about how bad Xarelto is”.

She is the latest of many of my patients who have been inundated with ads like these which state in very strident tones that a drug is bad and that if “you or a loved one has had a serious bleeding problem” contact 1-800-BAD DRUG and see if you are eligible for compensation.

These drugs are not bad and the only reason these advertisements are being played is that tort lawyers sense an opportunity to make money.

To understand why they are flooding the TV market now I will have to give you some background on atrial fibrillation , stroke and the drugs available to reduce stroke risk.

Preventing Stroke Associated With Atrial Fibrillation

Patients with atrial fibrillation are at increased risk of stroke and since the 1950s the only drug available for doctors to reduce clot formation in the heart and susbsequent strokes was warfarin (brand name Coumadin). Warfarin is only effective and safe within a narrow window and its effects are strongly influenced by Vitamin K in the diet and most medications. Thus, frequent blood testing is needed, and close monitoring of diet and changes in medications. Even with this close monitoring, serious and sometimes fatal bleeding occurs frequently with warfarin.

Novel Anticoagulants

In recent years, three new drugs for reducing strokes in patients with atrial fibrillation which are much less influenced by diet and medications have gained approval from the FDA. These are generally referred to as “novel anticoagulants” reflecting their newness, different effects from warfarin or aspirin, and their blood thinning properties.  The first  (brand name Pradaxa) was released to much excitement and fanfare in October, 2010.  The press release for this approval read as follows:

PRADAXA, an oral direct thrombin inhibitor2 that was discovered and developed by Boehringer Ingelheim, is the first new oral anticoagulant approved in the U.S. in more than 50 years. As demonstrated in the RE-LY® trial, PRADAXA 150mg taken twice daily has been shown to significantly reduce stroke and systemic embolism by 35 percent beyond the reduction achieved with warfarin, the current standard of care for patients with non-valvular atrial fibrillation. PRADAXA 150mg taken twice daily significantly reduced both ischemic and hemorrhagic strokes compared to warfarin

Differences Between Warfarin and the Novel Anticoagulants

What was very clear from the study with Pradaxa  and stated very clearly in all publications and patient and doctor  information sources was that just like warfarin, patients could have severe bleeding complications, sometimes fatal. Overall serious bleeding complications were about the same (the rate of major bleeding in patients Pradaxa  in the RE-LY trial was 3.1% versus 3.4% in the warfarin group) but Pradaxa had about 50% more bleeding from the gastrointestinal tract and warfarin about 50% more bleeding into the brain.

Another big difference between the novel anticoagulants and warfarin is that we have antidotes (Vitamin K, fresh frozen plasma) that can reverse the anticoagulation state rapidly for warfarin but none for the newer drugs. This information also was made very clear to all doctors prescribing the medications in the package insert and educational talks. Despite this, in the major trials comparing these newer agents to warfarin, the newer agents were as safe or safer than warfarin.

The Pradaxa Bad Drug Ads

Beginning about a  year after Pradaxa was released advertisements paid for by law firms seeking “victims” of Pradaxa  identical to the ones we are now seeing for Xarelto began to appear.

The Pradaxa ads went away in mid 2014 when these lawsuits were settled and almost immediately the lawyers began paying for Xarelto ads. Xarelto was the second “novel anticoagulant) to be approved by the FDA and, similar to Pradaxa, was proven to as effective as warfarin in preventing strokes with a similar rate of serious bleeding complications.

As the Wall Street Journal noted (with the catchy title “The Clot Thickens” and opening line “Is a blood thinner causing lawyers to smell blood?”)

“Spending (on Xarelto ads)  jumped to $1.2 million in July from just $8,000 in June, according to The Silverstein Group Mass Tort Ad Watch, which noted the number of ads that ran in July exceeded 1,800. …

The spending increased shortly after Boehringer Ingelheim, which sells a rival blood thinner called Pradaxa, last May agreed to pay $650 million to settle about 4,000 lawsuits over claims the drug caused serious bleeding episodes. The settlement likely emboldened attorneys to turn their sights toward Xarelto which, like Pradaxa, is one of a relatively new batch of blood thinners.”

The third drug to be approved for preventing strokes in atrial fibrillation was Eliquis. Data from the large, randomized study comparing it to warfarin suggest that it is more effective at preventing stroke than warfarin and significantly less likely to have bleeding complications. However, I predict that within the year (especially if the Xarelto lawsuits also are settled by its manufacturer) we will start to see lots of TV ads telling us that Eliquis is a BAD DRUG.

It’s important to remember that all drugs have benefits and side effects. Seemingly harmless antibiotics can increase your risk of dying suddenly (see here), rupturing your achilles tendon or developing a life-threatening colitis.

Xarelto is not a BAD DRUG. When prescribed to appropriate patients with atrial fibrillation with  appropriate precautions it prevents strokes which are potentially life-threatening or disabling. All blood thinners are two-edged swords: they stop good clots and bad clots.

Ignore The Ads

Patients are better off ignoring both positive, direct to consumer, advertisements, promoting these newer anticoagulants and negative, greedy-lawyer sponsored advertisements, soliciting “victims”.

Hopefully when your doctor discusses the choices of blood thinners with you he will present to you a balanced discussion of the pros and cons both of whether or not to take  a blood thinner and whether to take the old standby warfarin or one of the newer agents. An interactive discussion should follow in which your particular issues and concerns factor into the final decision.

 

Two Spades or Two Diamonds, Two Ladies and Two Studies

I saw two delightful eighty-something ladies recently whose cases highlight some important points about atrial fibrillation, stroke and long term heart monitors.

Ms. M was playing bridge and found that she had 7 spades solid (solid, Mrs M informed me, means you have 7 of the suit with all of the honors (ace, king, queen, jack). Instead of bidding 2 spades which she meant to do, she bid 2 diamonds, and her partner responded by bidding 5 diamonds. This miscommunication resulted in a disastrous hand for the pair.

Ms. K  told me she had had an episode of “mass confusion” two weeks earlier during which for 15 seconds her “thinking process was not working properly.”

These cases illustrate the subtlety and brevity with which transient ischemic attacks (TIAs) or mini strokes can manifest. In contrast to the normal forgetfulness that is associated with aging, these women recognized  a sudden, transient and disturbing major alteration in their baseline mental processing.

TIAs are basically strokes that resolve quickly, generally within 24 hours, and leave no residual symptoms. They are often a warning that larger, more permanent strokes will follow.

In both of these cases, when I first saw the patients, they were in normal or sinus rhythm but subsequent monitoring revealed atrial fibrillation (AF).

Cryptogenic Strokes

A quarter of the 500,000 strokes occurring annually in America are unexplained (the medical literature tends to use the exotic and Halloween-appropriate term, cryptogenic for unexplained strokes). This means that imaging of the brain and arteries to the brain finds no abnormalities that would cause a stroke and that the patient has no history of AF. Since there is such a strong association between atrial fibrillation, clot formation in the heart, and stroke, (see my post on AF here) doctors assume that an otherwise unexplained stroke in a patient with AF is due to a clot leaving the heart and landing in an artery to the brain. These patients benefit from medications which reduce the risk of clot formation (either warfarin or one of the newer anticoagulants everyone has been hearing about either from negative TV ads from lawyers or positive direct-to-patient drug company ads).

New evidence suggests that if we monitor the heart rhythm for 30 days of patients who have had unexplained strokes a significant percentage will manifest atrial fibrillation.

A Canadian study of 572 men over the age of 55 who had had a cryptogenic stroke or TIA found that atrial fibrillation lasting 30 seconds or longer was detected in 45 of 280 patients (16.1%) in those who underwent 30 day monitoring, as compared with 9 of 277 (3.2%) in those who were only monitored for 24 hours.

Another study evaluated 441 patients following cryptogenic stroke with half randomized to receiving an insertable cardiac monitor (we call these implantable loop recorders (ILR) in the US). The ILR is a small device that can be inserted under the skin in the left chest region and allows continuous monitoring of the heart rhythm. After 6 months, atrial fibrillation had been detected in 8.9% of patients in the ILR group, versus 1.4% of patients in the control group. At 12 months it was 12.4% versus 2%.

Neither of my two ladies felt palpitations (a sense of the heart beating irregularly) that would have suggested a problem with the heart. About half of my patients with AF will feel their heart fluttering or “flip-flopping” or racing when the heart goes out of rhythm but the rest of my patients feel nothing. Thus, AF can be silent and I have many patients whose first symptom was a TIA or stroke.

These two ladies and two studies have taught (or reinforced for) me the following:

TIAs can be very subtle. Patients need to be aware of transient episodes of significant confusion or speech difficulties and report them to their doctors. We doctors need to pay close attention when patients report such episodes.

The patient who has had a cryptogenic stroke or TIA should undergo long term cardiac rhythm monitoring looking for AF. My take on the literature at this point is that we don’t need to do the more expensive and invasive ILR. I think a 30 day monitoring device that is capable of automatically identifying AF is sufficient.