An Old Woman, Cows, and the Great Depression
The Amazing Story of Digoxin
Medical doctors were unable to treat a medical condition called dropsy in the 1700’s. Doctors at the time discovered that dropsy, or leg swelling/edema, often came with an irregular heart beat. Today we would call this irregular heart beat atrial fibrillation.
The treatment of heart failure and atrial fibrillation changed with the birth of Englishman William Withering in 1741. William eventually graduated from the University of Edinburgh in medicine. He had particular interests in chemistry, botany, and mineralogy. In 1775 he was asked his opinion about a recipe to cure dropsy – a recipe kept by the old matriarch of a local family. In reviewing the 20 or so ingredients, one ingredient stood out to him called foxglove. Foxglove is the plant in the image at the top of the article. Note the bee in the image. Incidentally a bee’s heart rate is about 1,320 beats per minute (This fun fact becomes important in the next paragraph).
In his study of this plant over the next 10 years he observed that when given to patients with dropsy, it reduced swelling by increasing urination. He also observed that it could slow the heart down to about 35 beats per minute, making the heart beat stronger (Now you know why bees go after foxglove).
Atrial Fibrillation is Common
That irregular heart beat observed over the centuries before our time is called atrial fibrillation or “afib” if you want to sound hip. You become more likely to get it as you add candles to your birthday cake. Currently, 1 of every 25 people over 65 years of age have afib. After 80 years, 1 in 10 have afib.
Afib is an Irregular Heart Beat
Atrial fibrillation causes the heart to beat irregularly. Normally, the heart beats at regular intervals – about 60 times per minute. In afib, the upper and lower parts of the heart get out of sync with each other. The lower chambers respond by beating faster and irregularly. Because the upper chambers, or atria beat fast also, they appear to twitch or fibrillate – hence the name atrial fibrillation. A great video animation is found here.
Afib Comes and Goes in Most People
Some people have afib every once in a while. Others are in afib all the time. Those that have it every once in a while, eventually get it more often until they are permanently in afib.
The Most Common Symptoms of Afib
The most common symptoms of afib are . . . NOTHING! Most people don’t even know they have it. That is not a good thing as many people are first diagnosed when they come to the hospital with a stroke from afib. You’re less likely to have symptoms if you’re diabetic or above 65 years of age. The most common symptoms however are a sense of an irregular heart beat, fatigue, reduced stamina, and shortness of breath with exertion. Less common are chest tightness and more frequent urination.
Diagnosing Afib
Afib can be easily picked up on an ECG (or EKG – same thing). Smart watches and an inexpensive device called a Kardia EKG Monitor can spot afib even if you don’t feel it.
Holiday Heart
Afib has a nickname called holiday heart as one of the triggers of afib is alcohol. Other triggers include strong emotion, exercise, poor sleep, surgery, and illness. I once treated a kid in his 20’s who got it from drinking Red Bulls to stay awake on the night shift – moral of the story – working is dangerous 🙂
Diseases that Cause Afib
Afib develops in people with heart disease, prior strokes, hypertension, COPD/emphysema, obesity, sedentary lifestyle, sleep apnea, hyperthyroidism, and alcohol use.
Lifestyle to prevent afib
The best lifestyle to prevent afib is:
1). Exercise vigorously 3-4 x’s weekly for 30 minutes at a time. Daily vigorous exercise is not as protective.
2). Improve sleep quality (less night time wake-ups, and treat insomnia) and sleep 7-8 hours/night.
3). Lose weight if overweight or obese.
4). Eat chocolate 2-6 servings a week.
5). Fast between dinner and breakfast. Don’t eat dinner within a 2 hours of bedtime and don’t skip breakfast.
In a picture, don’t be this guy:
The Two Decisions
If you’ve been diagnosed with afib it will not shorten your life if you answer the following two questions correctly:
1). Should I take a blood thinner?
2). Should I stay in afib?
Should I Take a Blood Thinner?
Afib can cause a heart attack -but not the normal way. Afib is actually more likely to cause a “brain attack.” Think about the heart like a house – afib is an electrical problem not a plumbing problem. But if you don’t fix the electrical problem you may get a plumbing problem. Afib can result in a blood clot going to the “plumbing” of your brain causing a stroke. I once treated a woman who came in with a heart attack because one of these blood clots went to her heart instead of her brain.
Your Stroke Risk
You should take a blood thinner if your stroke risk is elevated. You can figure out your stroke risk by calculating your score here. A score of 2 or more means you should probably go on a blood thinner.
The Amazing Story of Warfarin
Years ago if you were diagnosed with afib chances were you were going to get a stroke. There was no way to stop it. In fact, if the Great Depression hadn’t happened we wouldn’t have made a discovery that changed our ability to stop a stroke in afib. Ed Carlson was a farmer in Wisconsin in the 1930’s. Over the years he watched many of his prized cattle die from internal bleeding. He had weathered the Great Depression and like many farmers at the time, had little money. Cows ate hay – preferably dry hay. Damp hay grew mold and wasn’t usually given to cows. Because of the lack of money to buy more hay if their supply got moldy, many farmers fed their cows the wet, moldy hay. In the 1920’s many farmers noted that their cows would begin to show signs of bleeding about 15 days after eating the hay. About 3 to 4 weeks later, their cows would die of internal bleeding. Veterinarians recommended that the cattle not be fed wet, moldy hay, but many farmers like Ed, didn’t think that was good advice or they couldn’t afford to do anything different.
Fed up with the death of his animals, Ed loaded a dead cow into the back of his truck and drove 200 miles through a blizzard to the local agricultural experimental station. Finding the only open door in the building, he lugged in a milk can of the unclotted blood from his dead cow and set it before two very surprised scientists. Little did any of them know at the time, but that can of blood was about to change the course of medical history.
Karl Link, the lead scientist, that had met Ed Carlson that day spent the next 6 years of his life looking for the substance in the blood that was killing all the cows. The result of his work was the discovery of a compound called coumadin – a substance that prevented blood from clotting. Coumadin came to be called Warfarin in honor of the Wisconsin Alumni Research Foundation (WARF) that financed the research. Warfarin was initially promoted as a rat poison but its use to thin the blood was also recognized as useful to treat blood clots in the legs and lungs and possibly to prevent heart attacks. It eventually was used to treat President Dwight D. Eisenhower after his heart attack in 1955.
Blood Thinners Prevent Strokes
Today we have several medications to prevent strokes in afib including Warfarin, Eliquis, Xarelto, and Pradaxa.
Blood Thinners Can Sometimes Cause Serious Bleeding Problems
If you take a blood thinner you won’t bleed without reason. In fact, I’ve diagnosed two patients with kidney cancer because they noticed blood in their urine after starting these medications. However, if you cannot tolerate a medication to thin your blood, there is a “plug” device that you can put in the part of your heart where the blood clot is formed. This device is called the Watchman device; a really cool animated video of how it’s placed is found here.
Stay in Afib or Not?
The second decision is whether you should stay in afib or try to get your heart back into a normal rhythm. Remember one important thing – studies show that MOST people do just as well, if not better, staying in afib then they do back in a normal heart rhythm. That being said, there are a few people who do better staying out of afib. These are people with symptoms from afib, people who are younger (usually <65), and people with bad heart disease who’ve been newly diagnosed with afib.
Getting Out of Afib
Getting out of afib requires medications and medical procedures known as cardioversions or ablations. Cardioversion means shocking your heart (while you’re sleeping) to get out of afib. Here’s an animated video of a cardioversion. Ablations are a procedure where a tube is inserted into the heart to burn the part of the heart where the afib arises. Here’s an animated video of an ablation.
Choosing to Stay in Afib
If one makes the common choice to stay in afib, then medications are used to get the heart rate between 60-100bpm to prevent the second feared complication of afib known as heart failure (cue the evil music). A heart that beats faster than normal in afib can become weak leading to heart failure (Fun fact – the first description of atrial fibrillation may have been by a physician in China named Huang Ti sometime between 1696-2598 BC. He wrote: “When the pulse is irregular and tremulous and the beats occur at intervals, then the impulse of life fades”).
Van Gogh and Digoxin
One of the first medications to slow the heart rate in afib is digoxin from the foxglove plant. One well known recipient of foxglove was a French artist named Vincent Van Gogh who was given the medicine while living in an asylum. It has been felt for many years by some historians that Van Gogh had too much digoxin in his blood the last few years of his life. One of the side effects of foxglove is Xanthopsia which causes “yellow vision.” If you were to look at the paintings done towards the end of his life they are painted in vibrant yellows like this one:
Coincidentally, in 1890 one of his paintings highlights the foxglove plant in front of Dr. Gachet – but notice the lack of yellow hues. As much as some historians promote the digoxin story, we’ll never know for sure as yellow was very prominent in Van Gogh’s paintings even before he was put on digoxin.
Other Medications to Slow the Heart
You can use medications like beta blockers and calcium channel blockers to slow the heart down. Some beta blockers are metoprolol and carvedilol. Calcium channel blockers are diltiazem and verapamil.
Summary
Remember afib is an electrical problem not a plumbing problem. But not treating the electrical problem (afib) can cause a plumbing problem (stroke and rarely heart attacks).
Afib can cause two problems that are completely preventable with treatment: strokes and heart failure.
Most people can remain in afib for the rest of their life and will do fine if they take the right medications.