Guest Blogger Patrick Bailey – Why Athletes with Atrial Fibrillation Should Not Depend Only on Wearable Tech

Thanks so much to Patrick Bailey for writing this interesting and timely article.

Based on the available data from the Centers for Disease Control and Prevention (CDC), there are about 2.7 million to 6.1 million people in the US who experience atrial fibrillation (AFib): sometimes the heartbeats either are too fast or too slow.

That’s a lot of people and experts from the government’s health agency is expecting the number to increase since the US population’s average age is rising.

The prediction is that around 6 million to 12 million people in the US and 17.9 million people in Europe will be affected by atrial fibrillations in the next 30 or 40 years.

Currently, the condition contributes to around 750,000 hospitalizations each year and an estimate of 130,000 deaths.

Exercise may contribute to the onset or progression of AFib. There have also been studies about increased risks of AFib due to sports supplements and performance-enhancing drugs prohibited by the World Anti-Doping Agency.

AFib is often undiagnosed since the condition doesn’t always have symptoms that are immediately noticeable. The symptoms of AFib may include shortness of breath, chest pain, weakness, palpitations, lightheadedness, or confusion, but there are also people with AFib who sense no symptoms at all.

Thanks to recent technological breakthroughs, AFib patients, particularly athletes, are finding comfort through modern gadgets that can actually help them detect their condition.

Apple Heart Study

Dr. Mintu Turakhiathen, a principal investigator on Stanford Medicine’s Apple Heart Study, reported in March that preliminary findings showed promising results on the use of the Apple Watch to detect irregular heartbeats. The study, funded by the tech giant, was conducted virtually and involved more than 400,000 participants.

The goal was to find out if Apple’s ECG app can identify AFib with the use of the pulse sensor that measures the heart rate. The sensor is built-in electrocardiography found on the crown of the Apple Watch. Participants placed a finger on the watch’s crown to record their pulse rate for 30 seconds. Data from the watch was synchronized on a phone and then sent to the patient’s doctor for monitoring purposes.

Interestingly, the researchers found out that the gadget could help detect AFib before it happens.

Based on their findings, 0.5% of participants who receive notifications for irregular pulse rate, which could be indicative of an AFib. The researchers viewed this as an important finding since they are concerned with the possible over-notification of the gadget. Thirty-four percent of those who got notifications for irregular heartbeat did have AFib. The researchers also found out that 57 percent of those who got an irregular pulse alarm went to their doctors for proper medical attention.

Apps and Athletes

These latest findings are welcome news for athletes who are suffering from atrial fibrillation. Being the most common cardiac arrhythmia experienced by athletes, particularly those who are cyclists or runners, AFib is definitely a concern for endurance sports enthusiasts.

One of the challenges faced by these athletes is the management of the agents that control the rate and anti-arrhythmic medications that are linked to impairment of the athlete’s performance.

The latest findings of the Apple Heart Study, on the other hand, showed that a wearable can have a role in affecting a person’s behavior.

For instance, a 2018 article in Forbes gave a glimpse of how gadgets are being used to monitor student-athletes for heat exhaustion and other potential issues. Experts see that the study shows the potential of wearables on people’s wellness.

Wearables are usually used to track temperature, steps, metabolism, heart rates and even the athlete’s location. They are very convenient and they can be synchronized through the software’s cloud system.

Data can be viewed instantly and shared with coaches and even doctors. They don’t just come in the form of watches. Wearables can also be a compression shirt, a sports bra, a vest, or a belt.

The use of this technology has been viewed as critical in boosting athletes’ performance and pushing the athlete’s boundaries. They also are convenient to carry around.

Limitation of wearables

However, while the potential of wearable digital technology in preventive care was highlighted in the Apple Heart Study, some critics view it as too limited since it is not actually conducted in a randomized controlled trial. That is, it included no significant number of individuals not wearing the Apple Watch.

Some people have also expressed concern that it would be too risky to rely too much on wearables and not consulting health care providers.

This actually makes sense.

For instance, people who do not have AFib but receive alerts of irregular heartbeats might think they have a risky heart condition. While It would be best to seek medical attention, such false positives could cause panic, take a physician’s precious time away from other patients who truly need medical attention, and could even result in unnecessary catheterizations.

Properly minding wellness

No one is claiming that Apple’s smartwatch is medical grade, not even the study’s researchers. With that said, it’s still up to the individuals to take responsibility for their health. How?

Understand your body, speak up, and seek medical care. Wearables are not 100% accurate and cannot assess serious medical conditions.

Even the president of American College of Cardiology, C. Michael Valentine, said that although wearables hold promise to help patients and their health care providers in improving heart health, they “should be approached with caution.”

Valentine said information and data should be used responsibly and in coordination with evidence-based guidelines and tools.

Another limitation is cost. Unlike smartphones, not everyone has a smartwatch already, and they sell for more than $300 each. Not everyone could afford it.

AFib has been known to increase the chances of stroke by five-fold and a patient’s mortality by two-fold. Even too much physical activity can aggravate an AFib’s patient’s condition. It would be good to be able to track down one’s heart rate, but it would be best to know our body’s limitation.

The best way to reduce the risk of AFib, according to the American Heart Association, is to promote a healthy lifestyle. Get regular physical activity. Manage high blood pressure.

If diagnosed with AFib, get proper medication and maintain a healthy weight. If you suffer from substance abuse, get proper rehab drug treatment.

While tech companies are keen on creating gadgets that will be part of the people’s lifestyle including for those with health concerns, the public should always keep in mind the basic needs to get healthy.

pbailey

 

Patrick Bailey

http://patrickbaileys.com/

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Guest Blogger Adam Durnham – 5 Athletes that have Atrial Fibrillation

Special thanks to writer Adam Durnham who has kindly sent me an article he wrote on atrial fibrillation and athletes – You are truly appreciated Adam!

 

5 Athletes that have Atrial Fibrillation

Atrial fibrillation (AF or AFib) is an irregular or quivering heartbeat that can lead to heart failure, blood clots, stroke, and other heart-related complications. According to the American Heart Association, approximately 2.7 million people in the United States live with AFib.

During AFib, instead of beating effectively to move blood into the hearts ventricles, the upper two chambers of the heart (the atria) beat irregularly and wildly. Some people experience no symptoms of this medical condition and become aware only during a physical examination. For those who do experience symptoms, they often include:

  • Heart palpitations
  • Shortness of breath
  • Weakness
  • Fatigue
  • Confusion
  • Lightheadedness
  • Chest Pain
  • Reduced ability to exercise
  • Dizziness
  • Sweating

Different Types of Atrial Fibrillation

Atrial fibrillation symptoms are typically the same; however, the underlying reasons and the duration of this medical condition help to classify the different types of AF problems. The different types include:

  • Occasional – With occasion AFib, symptoms may come and go and may last only a few minutes or hours and end on their own.
  • Persistent – With persistent AFib, the heart rhythm does not return to normal on its own. In order to restore normal heart rhythm, the patient will need treatment such as medications or electric shock.
  • Long-standing persistent – With long-standing persistent AFib, the condition is continuous and persists for more than twelve months.
  • Permanent – With permanent AFib, there are no further attempts to restore normal heart rhythm and the heart rate is often controlled by medications.

Atrial Fibrillation in Athletes

AFib is the most common arrhythmia seen in athletes. This is especially so for middle-aged athletes, although it can be seen in young athletes as well. Here are five athletes who have atrial fibrillation and how they handle the condition:

Larry Bird  NBA legend, 12-time All-Star, three consecutive regular-season MVP awards, Boston Celtic Larry Bird suspected he had problems with his heart while still playing his beloved game but never told the team physician. It wasn’t until he retired in 1992 that he was diagnosed with atrial fibrillation. He claims his symptoms which included rapid heart rate, disorientation, and light-headedness, are now under control.

Jerry West – The 14-time NBA All-Star guard Jerry West who played for the Los Angeles Lakers from 1960 to 1971 was unaware he had symptoms of atrial fibrillation while he endured sleepless night, heavy breathing, and anxiety. West remembered breathing into paper bags during halftimes to help with his hyperventilation. He described these episodes as panic attacks. It wasn’t until his heart raced out of control after he became the coach and general manager of the Lakers that he was diagnosed with atrial fibrillation. To restore a normal heartbeat West was treated with cardioversion. Cardioversion is a procedure that utilizes a low-energy shock to the electrical system of the heart for the purpose of restoring normal heart rhythm. However, after this procedure, his AFib persisted and after 40 years with the NBA he retired.

Haimar Zubeldia – Spanish cyclist and Tour de France race Haimar Zubeldia, announced in 2012 that his AFib condition forced him onto the sidelines for a period of three months. Although his physicians explained to him that AFib could end his career, Zubeldia returned to the sport after treatment and weeks of rest. His was determined to remain competitive in the sport and finished sixth best overall that year in the Tour de France.

Karsten Madsen – Triathlete Karsten Madsen felt faint and short of breath in 2010 after a routine fitness test. He was diagnosed with atrial fibrillation at that time. He was informed by his doctors that he would need to undergo cardioversion to restore normal heart rhythm. Madsen’s doctors reassured him that he can continue to train, and he has his condition monitored closely.

Billie Jean KingIn 2015, the legendary tennis champ Billie Jean King went into atrial fibrillation. After visiting a cardiologist, she was diagnosed with AFib and prescribed daily medication. In addition, she also underwent an ablation to destroy abnormal tissue that may cause arrhythmia. King has teamed up with Janssen Pharmaceuticals to raise awareness about atrial fibrillation and to educate those with AFib about their risk for afib-related stroke.

If you or someone you know has symptoms of atrial fibrillation, it is crucial to seek medical attention immediately to reduce the risk of complications.  If a person is a heavy drinker, it is important they get rehab services as this can affect their heart condition. Do not waste time if a loved one you know suffers from a-fib and drinks heavily.

Guest Blogger – “Old Runner”

“Old Runner” is a seventy five year old well seasoned runner still running marathons with atrial fibrillation. I find him to be truly inspirational.

 

 

It was November, 2002, at the NYC marathon. I had previously run 15 marathons over a period of eighteen years, none slower than four and ½ hours.

This one was going to be five hours and 15 minutes!

I experienced shortness of breath while running to the side of the street and high-fiving the kids watching from the sidelines. I had to walk the bridge decks (the only change in elevation on an otherwise flat course.)

Suffering no ill effects from this race, I kept on running over the years, experiencing occasional periods during a training run where I had to slow to accommodate perceived extra effort without any change in actual pace. These episodes would pass after a few minutes and I could resume my normal pace again.

Then, in 2007 I passed out in the bathroom while urinating (the doctors have a word for this phenomena which I can’t recall). I went to the hospital for observation and after a stress test was diagnosed with right atrial fibrillation. An ablation procedure changed nothing.  Another doctor I visited said he would not have performed the procedure; when I asked why he stated, “too many trigger points”.

Today I’m seventy five years old, a veteran of 37 marathons. I haven’t run a marathon for a couple of years, my most recent half marathon was last year. I’m still running but most of my runs include some walking. My A-fib is on and off, meaning I go in and out of fibrillation, I have no idea when this occurs any more just that it does occur. A stroke is the biggest danger I face with this form of a-fib so my cardiologist prescribed “warfarin” a blood thinner.  At 75 years of age my pace is closer to twelve minutes a mile, which is a bit depressing, but it is what it is and I know moving is the most important thing I can do for my health – so I keep moving.

Signing out,

“Old Runner”

 

 

Guest Blogger – UK AFib Runner Mike Munson

This is an amazing story from a British AFib Runner, Mike Munson. This guy is truly hard-core and persistent. Non-runners who read this will be shocked, but I think most endurance athletes with atrial fibrillation will “get it.” Mike has been a gifted athlete over the years – his times when he was having to walk and jog because of an AFib attack are probably faster than my PR times! He initially dealt with attacks of atrial fibrillation, and eventually had to deal with (probably unrelated) cardiac arrest and coronary artery disease. Please feel free to comment. Thanks for sharing your story, Mike!

 

I had run regularly since about 1964 when I won my local district schools 1 mile in 5m 4secs (aged eleven) on a grass track, bare footed (the school did provide spikes but they hurt my feet). I joined my local Athletic club at twelve, running Track & Field in the summer, Cross Country in the Winter at County & National level. After University I worked in Africa but ran hard most days and started running slightly longer distances in hot climates in Central Africa (ie 10km & 10 Miles). I didn’t race much but did my first 10k in Lagos, Nigeria.

On returning to the UK in my mid 30’s and just starting a family I eased up on the intensity of my training but still ran most days and competed regularly for my local Running Club. As a club we had an internal “Grand Prix” where we competed against clubmates of similar ability.

In late 2000 (aged 50) I was taking part in the last 10km of the year, a relatively easy course that would normally have taken me about 40 mins to compete. I was a very consistent runner and usually started slower and ran negative splits. On this occasion I found myself collapsing for no apparent reason within a few hundred metres of the start. As it was the last run of the series (& I am not one to give up anyway), I picked myself up and initially started walking then broke into a jog, but very quickly had to stop again. I had no idea what was happening but by stopping and walking and jogging very slowly I eventually got round but really collapsed at the finish in around 60min . I went to see my GP the following morning and she sent me straight to Hospital. On doing a test on the treadmill they noted I had an irregular heartbeat, but didn’t do anything about it.

Over the next few years the attacks increased from every few months to every few weeks and seemed to be quite random, although I tried to work out if by running at a particular pace or warming up longer would help. If an attack occurred in a race I tended to stop  and walk to the finish as I was coaching youngsters and didn’t want them waiting around too long for me  if I ran to collapse .

In 2006 I moved to Suffolk and introduced myself to my new GP who happened to be a runner. He immediately referred me to a Cardiologist at the local Hospital who had me tested immediately and then transferred me to Papworth (Our Regional Cardiac Centre). They carried out an ablation which unfortunately didn’t work and I still have AFib. However I was given medication (Flecainide ), this had side effects of dizzy spells and blackouts which became very regular. Some of my friends found me a bit blasé about my collapsing and I was often heard to say to a fellow runner who might have stopped to help me, “Oh it’s no problem, I just have a heart problem.” Sometime they would be very shocked but would still try to encourage me to get up quickly and run fast to the finish but all I ever wanted was to get to the finish at my speed, which sometimes could be quite fast and sometimes I would be walking through the line. I became incredibly inconsistent. Over the past 25 years I have been in clubs that had 5km handicap championships each summer. Previously they would very by under a minute over the season but latterly on a good day (prior to going on beta blockers) I could vary from 22 to 31mins, depending how many times I collapsed.

All this time my pace was getting slower as I was unable to train properly (ie more than I would have expected due to my getting older), although one time I spoke to my GP about it an she said “don’t you realise you are getting older” to which I replied yes but I am slowing down too much!

 Therefore I turned to trail running with self navigating. This became very enjoyable and I particularly enjoyed the refreshments at check points, however by 2013 I was getting concerned about my ability to compete longer events and started collapsing and feeling sick if I tried pushing the pace at all. I spoke to my GP who arranged a 24 hour monitor. During this period we had our club 5km championship so I was happy to test myself with the monitor on. Please bear in mind I had been assured that  Afib wouldn’t kill me by my GP.  About 400m from the finish I had a black out  and I went down. A friend was just behind me, checked on me, I had come to and told him I was OK and would walk to the finish. He informed the next official who advised him I was now just behind him. In fact I recovered so quickly I actually overtook him before collapsing again near the finish. I returned the monitor to the Hospital the following day and soon after getting home a Consultant called me to come in immediately but I shouldn’t drive. I was kept in for tests, but in the end they changed my medication to a Beta blocker, which did stop the dizzy spells and blackout, however, my pace in training immediately slowed further from around 8 minute mile to 10 minute mile.

I was then doing more Trail Marathons as it didn’t seem to matter what pace I ran and was good fun, whilst still a challenge and hopefully keeping me fit. 2016 & early 2017 I found when doing easy Trail Marathons increasingly I was struggling over the last few miles, even contemplating taking short cuts, not wanting to cheat but just to finish. I did actually collapse twice at the finish and on one occasion the paramedic suggested going to A&E but I felt I would be OK in the morning (and of course I was).

Then 4th June 2017 I was in the 25th mile of the Stour Valley Trail Marathon (a fairly tough race with several long hills which was my 7th Marathon of the year) on one of the warmest days of 2017 in England, when I collapsed with an SCA (sudden cardiac arrest). Apparently this may be nothing to do with my Afib.

I had an ICD fitted and it has triggered twice since (during runs/ long walks as I am supposed to be taking it easy) and I have now had a double bypass as 2 arteries were narrowed. I am now doing Cardiac Rehab and hope to get back running soon, but will be patient (especially after dying last year for 25 minutes). However the Afib is still with me and I am still on 3.75 mg Bisoprolol.

 However now my wife carefully vets anyone giving me a lift. The guy who gave me the lift on that fateful day is still not allowed to drive me.

The local running community have been great. As I lost my driving licence friends have driven me around. As I could run last winter the local Cross Country League have let me walk the ladies distance. Unfortunately my last collapse meant I missed the penultimate race as I was in Hospital, so as race Director I was busy sending messages out to get the race on. At the Presentation night I was given a special award which was very humbling. I was the first recipient of this award named after a regular runner who had passed away in the previous season.

This summer as I have not been allowed to run I have been raising money for local cardiac charities by organising 21 Trail runs in my County on Wednesday evenings, starting at a Village Pub and using Public Footpaths. It is a simple concept whereby we sell an instruction sheet for £2 and runners self navigate round one of 2 routes either short (maybe 3-4 miles) or longer 6 + miles and then finish at the Pub. We sometimes put on additional things, like one night we tested people for AFib before they set off. This was well received and 120 people turned up; however I was the only person testing positive for A Fib! It created a fair amount of awareness and we managed an article in our Regional Daily.

Is this the sort of thing you wanted to see?  My family have been very supportive of me as they saw me in Hospital with tubes in me etc and where told that maybe I wouldn’t survive the induced coma and if I did as I was out for 25 minutes I might have brain damage but I seem to be very lucky!

Best Regards Mike Munson (aged 65)

Guest Blogger Request

Note: This is a post I made on a couple of atrial fibrillation Facebook groups – specifically:

Healthy Hearties

and I’m including it here in the hopes that readers will be inspired to write and share. Thanks!

Joey and I hiking on the nearby Pacific Crest Trail

I write and maintain A Fib Runner (afibrunner.com) – a blog about atrial fibrillation and trail running, ultra running, mountain biking, and other endurance sports. Studies have shown that atrial fibrillation is much more common in middle-aged athletes than in non-athletic individuals of the same age – doesn’t seem fair, does it? I’m a marathoner, ultra-marathoner, hiker, mountain biker with permanent atrial fibrillation – and I blog about it.

I would like to request guest bloggers to submit articles. I’ve written a lot about *my* experience; but your experience is going to be unique and will be of great interest to readers of the blog. At this point I have had several people send me articles and they have been very popular – some of the most popular articles on my blog.

So here’s how it works: if you’d like to submit and article let me know via comment or message. I’ll send you my email and we can get started. If writing intimidates you that’s fine – just right it in your own voice, like you are writing a letter to a friend.

If you want to use your full name – great! A lot of athletes with atrial fibrillation come from a generation that values privacy a little more than millennials – that’s fine. My 58 year old life is an open book, but maybe yours isn’t – a first name or even a pseudonym is fine. I’ll edit the article for spelling, grammar, punctuation, etc., and send you a revised copy (if there any revisions) for your approval.

If you’d like to send photos I’ll let you know how I do that. Blogs need photos – but if you have none to share I will provide appropriate photos.

The article should be about your experience and NOT about giving medical advice. Personally, I try very hard to write as an A Fib Runner and not as a health care provider. If you are a cardiologist, or other type of health care provider, and would really like to make suggestions we can discuss that. Clearly there are some real liability issues with giving medical advice over the internet.

Any topic involving atrial fibrillation is appreciated, and I especially would like to hear from people who have had various treatments like ablation, a watchman device, or an Atriclip, as well as the various medications that you’ve used for atrial fibrillation. How did you find out you had a fib? What did it feel like? What is your emotional reaction to a fib? What is your psychological response to the new normal of a fib? What was your cardio version like? What are your triggers? What things did you change after the diagnosis was made? Did a fib destroy you or did it strengthen you?

And so on.

Please let me know – THANKS!

A Casualty of My Atrial Fibrillation: My Single Speed Cross Bike

I miss my Bianchi San Jose.

It’s true that a person could easily get by with one bike – most people in the world do just that. If I only was going to have one bike it’d be a nice mountain bike – because it could be ridden in all conditions, four seasons, on or off road, and it’s usually a comfortable ride.

But I’m a typical middle aged (employed) male cyclist – I have three bikes – a mountain bike, a road bike, and a cross bike.

Okay – I‘ll admit it – I actually have four bikes. My fourth bike is my “legacy” bike – the first fine bike I ever owned that I had to  save up for about a year as a poor graduate student – my 1981 Trek 930 Sport Touring road bike with the Columbus tubing and the mix of Campy and Sun-tour components. I haven’t ridden it in nearly twenty years but I just can’t part with it – we had so many incredible road rides back in the eighties! My old bike is actually featured on the Vintage Trek website.

Alright – full disclosure – I still have the frame and (non-suspension) fork from my 1990 Fischer Supercaliber – still my favorite mountain bike of the several I’ve owned for the past thirty years.

But out of the three bikes I actually ride the most frequently ridden is my full suspension cross country 29er mountain bike – a real beast built for the clydesdale that I am.

I also have a carbon Giant Defy (their knock off of the Specialized Roubaix) that I bought as a retired rental fleet bike from the local bike shop. Yes – I know that you’re never supposed to buy a used, god forbid a former rental fleet carbon framed bike – but the extra large sizes are so infrequently rented that it had very few miles on it.

But my Bianchi San Jose is the one that was a casualty of my atrial fibrillation (AF). A single speed cross bike – perfect for cruising on our local Rails to Trails (OC&E and Woods Line State Trail) geared perfectly for the relatively flat trail (Trains can only handle so much steepness – no more that a 2% grade) and because it was a cross bike it was ideal for the nine miles that are paved as well as the ninety unpaved miles. Although it’s a single speed it had brakes – it wasn’t quite a hipster messenger fixy. I think those things are nuts – especially now that I’m anti-coagulated.

If you’ve never ridden a single speed – give one a try – a very smooth and quiet ride. My San Jose was a little tricked out. I upgraded the tires to a more aggressive set, and I had a beautiful Brooks Saddle (which I kept) and some matching but really over-priced Brooks leather handle bar tape. That bike just had a terrific look and feel – the most comfortable bike I’ve ever had. I could ride in the drop position for a long time without getting sore.

But regrettably as my AF got worse and the medications were going up to higher dosages (Thanks, Carvedilol!) I could no longer ride it up to the hill to our house. It isn’t the biggest or steepest hill in the neighborhood (we live in the mountains, after all) but it is about a 250 foot climb in about three quarters of a mile (75 meters in 1.2 kilometers). It never was an easy climb on the single speed, but currently it is impossible for me.

To be honest I never was a good single speed cyclist. I’ve always had a fast cadence and used a lower gear, and I tend to shift constantly maintaining an even power output. I’ve ridden with guys who just stay in the higher gears and grind – not my style. It was always a challenge getting up that hill in the single 42/17 gear.

I considered getting an after market three speed hub for the back but that would be too dorky. I  still rode it on the bike trail but I’d have to drive to the trailhead schlepping the bike on my truck’s bike rack. Eventually I traded it in at the bike shop when I bought my most recent bike – a Specialized AWOL – sort of a gravel grinder meets full touring bike.

I like the AWOL well enough, and ride it frequently; but compared to the light, sporty, cool looking San Jose the big, clunky, awkward looking AWOL seems more like riding around in a UPS delivery truck. Oh well – life changes as you go – I’m grateful to  still be riding.

Please feel free to share your comments.

Is Digoxin a Good Choice for Treatment of Atrial Fibrillation?

Is Digoxin a Good Choice for Treatment of Atrial Fibrillation? I want to make it clear, once again, that I am writing this blog as an endurance athlete dealing with atrial fibrillation (AF) – not as a clinician. I’m not a cardiologist or a primary care physician. I’m simply posing a question and not answering it. It is important for you to be in agreement with your cardiologist and primary care provider about your treatment plan Whatever you do – DON’T STOP TAKING ANY MEDICATION YOU HAVE BEEN PRESCRIBED BECAUSE YOU READ ABOUT SIDE EFFECTS ON SOME GUY’S BLOG!

Also – full disclosure – I take a low dose of digoxin.

Digoxin is the generic name for Lanoxin which has been actually been used for hundreds of years as an herbal preparation (Digitalis) from the foxglove plant, seen above, which is a lovely plant, don’t you think?

Digoxin is used to treat atrial fibrillation, atrial flutter, and heart failure. My cardiologist told me that many of the younger cardiologists don’t generally even prescribe it any longer.

Digoxin has a narrow therapeutic index, which means that at too low of a dose it isn’t very effective and at higher doses it is toxic. Because of this it has many side effects. It is unknown whether digoxin is safe during pregnancy. Digoxin works by improving heart function by strengthening the contractions and slowing the heart rate.

A 2018 paper published Journal of the American College of Cardiology concluded that digoxin increased mortality in patients with atrial fibrillation regardless of heart failure.

Conclusions In patients with AF taking digoxin, the risk of death was independently related to serum digoxin concentration and was highest in patients with concentrations ≥1.2 ng/ml. Initiating digoxin was independently associated with higher mortality in patients with AF, regardless of heart failure.

Yikes!

Also consider that several of the authors of the study disclosed that they had financial ties to pharma and medical device companies, including pharmaceutical giants Bristol-Meyers Squibb and Pfizer who funded the study.

But look! Runners and other endurance athletes need to ask their cardiologists about digoxin toxicity because both dehydration and low magnesium increase the chance of toxicity. Who among us hasn’t been dehydrated?

I’m going to be asking my cardiologist more questions about digoxin next time I see her. As I mentioned I take a small dose and when we did lab work my digoxin level was low, below the therapeutic window, which she said was fine – she just wanted to make sire it wasn’t too high. Me too!

I’d love to see your comments!

Dehydrated Trail Runner – me!