MI:Journal

CW: It’s settled–Long-term extreme endurance exercise is not heart healthy

JUNE 6, 2012

My inbox lit up this week with links to mainstream media reports that extreme exercise causes heart damage.

Sure enough, a group of US researchers published an exhaustively complete review article on the Potential Adverse Cardiovascular Effects from Excessive Endurance Exercise. (Full text available.) Though published in the modestly circulated journal, Mayo Clinic Proceedings, this article makes a serious impact.

Through this type of essay writing activities, students may learn about various concepts by getting in their basics. For instance, not every student will prefer The Scarlet Letter, even when you are expected to get through it. Students with learning disabilities are most likely to become frustrated if they’re not able to cope up with the remainder of the class. Click the ladybug alarm to seek out much more information concerning it.

In this post I will attempt to recap–in my language—why these authors have garnered significant attention in the mainstream media. As I go through the ten topics addressed in the paper, I’ll report the findings and add in a typical naysayer’s view.

(I apologize in advance—this is a longer post than I like to write.)

Some basics:

This paper offered absolutely no new data. It was a review article—a really terrific one, but still a review. In fact, many of the studies cited have been previously discussed on this blog. Why the media buzz then? Perhaps it was the power of putting all the evidence together (including 68 scientific references) in one paper? Perhaps it was just that Yahoo news published the paper? Perhaps its appeal has something to do with non-exercisers reveling in the exposure of chinks in the armor of the super-fit. Hubris has this effect.

The review article was split into ten sections. I’ll call them chapters.

Chapter 1: Regular moderate exercise is beneficial:

The authors start smartly. They begin by citing the many studies that document the long-term benefits of modest amounts of regular exercise. Two studies in particular show a U-shaped pattern of benefit: that is, to get maximal health benefits, one must exercise enough, but not too much. This Taiwan Study of more than 400,000 patients published in the Lancet nicely demonstrates a leveling off of benefit after one hour per day of exercise. I won’t spend much time here because this is so obvious.

Chapter 2: Sudden Cardiac Death and Endurance Exercise:

In this section, the authors cite the recent NEJM article on the safety of marathon running. As previously noted on this blog, the risk of suffering cardiac arrest in a marathon is extremely low (1 in 100,000), and not changed with the increasing numbers of marathon participants. Triathletes have double this risk, mostly because of an increase in deaths during the open-water swim (for obvious reasons.)

Chapter 3: Animal Studies:

It’s no surprise that the authors led with the famous and elegant Marathon Rat study. This powerful study is worth a review: Canadian researchers studied two groups of rats. One group ran like crazed ultra-marathoners and the other group remained sedentary. The running rats developed enlargement of all four chambers of the heart, abnormal heart stiffness, an increase in heart scar tissue and an enhanced susceptibility to dangerous heart rhythm problems. Ouch.

Of course, the skeptics counter that this was a rat study, and therefore might not apply to humans. So noted.

Chapter 4: The Athlete’s Heart:

The authors nicely summarize what an “athletic heart” means. Here is their thought process: Long-term endurance exercise, especially chronic aerobic exercise, induces adaptations in the heart, including increases in right and left ventricle volumes and wall thickness, increases in the overall mass of the heart, and enlargement of both atria. The striking thing about these adaptive changes is that when they occur in normal people, they are thought to confer a bad prognosis. Which is it then? Bad or good? The authors go on to cite four studies supporting the idea that ‘athletic’ changes may not be entirely benign. One study even notes enlargement of the heart can persist long after de-conditioning.

Naysayers look at these reports and rightly point out that they are non-randomized look back studies of small groups of extreme athletes. Noted again.

Chapter 5: Biomarker Evidence with Extreme Exercise:

At least five studies confirm that up to 50% of marathon finishers show elevated levels of cardiac enzymes. You know, the same chemicals released during a heart attack.

The authors use the rest of this section to speculate on the significance of exercise-induced enzyme rises. Using phrases like, “this may reflect myocardial cell damage at sites of myocyte slippage,” it’s easy for a reader to take notice. Does exercise cause such violent slipping of heart cells so as to spill enzymes? For a blogger who has been on many a long run or ride, these are scary words.

To the authors’ credit, they admit to not knowing the significance of elevated enzymes post stressful exercise. Good for them.

Chapter 6: Extreme exercise and adverse structural remodeling of the heart:

This section details the scariest aspects of long-term exercise. Extreme exercisers might want to skip over the upcoming paragraphs.

Two important reminders: the human heart does not regenerate itself—scar remains scar—and, you only have one heart.

The authors set the tone well by telling us that intense exercise can increase the cardiac output from 5 liters per minute at rest to up to 25 liters per minute during exercise. Think about that for a minute—pumping 25 liters of blood per minute for a 12-hour Ironman! (Sorry for the hyperbole.)

Let’s look at a few of the studies that were reviewed. As I wrote about previously, this Australian study examined the immediate damage to the heart (particularly the right ventricle) after major endurance events. The sobering report had three major findings: 1) Athletes finishing major endurance tests had elevations of heart enzymes, and the amount of leak paralleled dysfunction of the right ventricle. 2) Longer duration events  predicted more right ventricular muscle weakness. 3) Scar was seen on MRI scans in 12.5% of athletes and was more likely to occur in longer events. The conclusion here was that extreme exercise can induce right ventricular abnormalities while largely sparing the LV. The only shred of good news was that in most (but not all) cases, the damage was transient.

Further implicating the right ventricle’s susceptibility, the review paper highlighted a study demonstrating a strong relationship between abnormal right ventricles seen on MRI scans with the presence of ventricular rhythm problems. More than half of athletes with ventricular rhythm issues had RV scarring.

Unfortunately, RV scarring is not the only exercise-induced structural change of the heart. Take this German study of 100 experienced marathoners that were compared with regular age-matched controls. Patchy scarring (on MRI scans) of the heart were seen in 12% of runners—three-fold more often than non-runners. The kicker here was that over 2 years of follow-up, marathoners had more coronary events than non-runners. Again, the review paper cites numerous other similar studies.

Skeptics will continue to emphasize the fact that these studies are small and non-randomized. Okay, I hear that. But the evidence is mounting.

Chapter 7: Extreme exercise and changes in the coronary arteries:

This section focuses on the well-established finding that marathon running increases the likelihood of having calcium deposits in the coronary arteries. It goes without saying that coronary arteries fare better when not hardened and stiffened by the presence of calcium. Most damning is this German study of marathon runners: not only did the runners have more calcium in their coronaries, but most remarkably, the supposedly extra-healthy runners experienced the same frequency of heart attacks as a group of patients with known heart disease! A similar study was presented at the ACC meeting in 2010, and was covered in this piece on theHeart.org.

Again, the counter argument centers on the lack of comparative studies done over the long-term.

Chapter 8: The Pathophysiology of extreme exercise:

Pathophysiology is medical speak for abnormal adaptations that occur with long-term exercise. In this section, the authors mostly speculate that extreme exercise causes heart damage by inducing excess inflammation. A few studies confirm the presence of high levels of chemical markers of inflammation in extreme exercisers. There’s not much else to say here other than many studies implicate excess inflammation as the mediator of heart damage from excess exercise.

Chapter Nine: Extreme exercise and electrical abnormalities:

I’ll keep it succinct. The data speak for itself. Long-term exercise results in a five-fold increase in the risk of developing atrial fibrillation. The authors cite twelve papers supporting this obvious truth.

AF isn’t the only arrhythmia seen in the super-fit. As supported by five studies, ventricular arrhythmias occur commonly in endurance athletes. It’s worth recalling the marathon rat study, which showed a greater susceptibility to arrhythmia induction in the running rats.

I witness these findings nearly every day. Skeptics can deny the association of excess exercise with arrhythmias–but they would be wrong.

Chapter 10: Risk assessment:

We simply do not have cost-feasible means to identify those exercisers who either suffer heart damage or are at risk of damage.

One potentially promising strategy might involve doing coronary calcium CT scans in highly selected marathon runners. I hesitate writing that last sentence because it’s pure speculation, formed in my head by a couple of tragic cases of marathon runners who suffered heart attacks and at cath were found to have rock hard coronary arteries.

The Mandrola take home:

Step back and look at the big picture here. When you lay out all ten chapters on a canvas, the picture takes shape. Your conclusion should be the same as the authors:

In some individuals, extreme exercise causes severe heart abnormalities.

Many questions remain. The dose of exercise that causes damage is unknown, as is an individual’s susceptibility to varying training loads. We don’t know the ideal exercise regimen, or if there is one. I know what is too little exercise; I know what is too much; but there’s a large space in between.

I’ll finish with the obvious…

Just like everything else in life, even exercise has an upper limit.

JMM

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Related posts:

CW: More bad news for the (extreme) endurance exerciser
CW: Believing the future will be better…is heart-healthy?
CW: Is the Ironman triathlon heart-healthy?
CW: That exercise has an upper limit makes perfect sense

DENVER (CBS4) – Chest pain is considered the hallmark symptom of a heart attack, but patients can also experience other kinds of pain, and in some cases, none at all. That’s especially true for women, and they can be missing the symptoms.

Researchers say younger women have a greater risk of dying from a heart attack. A new study in this week’s Journal of the American Medical Association indicates that may be because their warning signs are often very different.

Lalina Franklin was having neck and jaw pain. She had no idea she was on the verge of a severe heart attack .

“You think of some really bad pain in your chest and collapsing. I wasn’t having any pain at all in my chest,” Franklin said.

New research shows 42 percent of women under 55 do not feel chest pain during a heart attack. And hospitals often don’t diagnose those women properly until it’s too late.

“When women arrive to the hospital having a heart attack with symptoms different than chest pain, their care might not happen as immediate,” cardiologist Dr. Suzanne Steinbaum said.

Researchers say that’s why more than 14 percent of women are dying from heart attacks in the hospital compared to 10 percent of men.

Doctors say there are signs a woman can look out for besides chest pain.

“They might have other symptoms like jaw pain, back pain, shortness of breath, nausea, fatigue and simply sweating. All of these things could be a heart attack,” Steinbaum said.

Steinbaum says for any woman noticing those symptoms, getting help immediately could be critical.

“The quicker you can get to treatment the quicker we can save heart muscle and prevent you from dying,” she said.

Franklin had a stent put in to clear an artery.

“I am definitely lucky to be alive today,” Franklin said.

Now at 60 she says she feels much better.

The study stresses that chest pain and discomfort are still the primary symptoms of heart attacks, whether a man or a woman. But researchers say don’t ignore other kinds of pain as well.

Doctors also say every woman starting at age 20 should have her cholesterol and blood pressure checked on a regular basis to assess her heart attack risk.

The following is an excerpt from the Summer 2011 issue of, “The Weatherhead P.E.T. Imaging Center for Preventing and Reversing Atherosclerosis’s” newsletter called, “P.E.T. News”.

New study about HDL cholesterol Treatment
The National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health has stopped
a clinical trial studying a blood lipid treatment 18 months earlier than planned. The trial found that adding high
dose, extended-release niacin to statin treatment in people with heart and vascular disease did not reduce
the risk of cardiovascular events, including heart attacks and stroke. This report has prompted lots of calls from patients wondering whether they should continue taking Niaspan.

Before taking any action based on this study alone, we always take a careful look at how the study was conducted and how it compares to other studies looking at the same issue. The results of this study are CONTRARY to several other large randomized trials that show a substantial benefit from raising HDL cholesterol. The data on the recent Niaspan trial has not been published in the medical journals yet so that it cannot be adequately evaluated.

However, several points stand out as follows:
1. The study showed no harm, but was stopped due to a reported lack of benefit without specific data provided
until this fall.
2. The patients selected had weighted average baseline LDL of 74 and HDL of 34. The HDL increased by 20%
to approximately 41 with Niaspan. Thus, the baseline lipids were not as severe as we commonly see in patients
with higher LDL, higher triglycerides and lower HDL. The study failed to achieve our HDL target of 45 to
50mg/dl and also failed to achieve the lipid and weight goals of our program.
3. The randomized, well done, definitive FATS and HATS trials of triple therapy including niacin showed
an 80% to 90% decrease in coronary events, the greatest benefit of any treatment ever reported for coronary artery disease and nearly double the benefit from statins alone.
4. Niaspan also changes the LDL and HDL particle size to the larger fluffier cholesterol particles such that
the larger LDL particles are less atherogenic and the larger HDL particle size provides more effective reverse
cholesterol transport out of atheroma thereby lowering atheromatous risk.
5. No drug therapy is a substitute for healthy food, lean body weight and exercise. The healthy living combined
with drug treatment to correct all lipid abnormalities is more effective than either approach alone, as shown in
the randomized HATS and FATS trial as well as the nonrandomized trial at the University of Texas.
We are not advising our patient to stop Niaspan as a result of these news reports. A large body of scientific data
indicates that Niapsan combined with other medications is beneficial, not contravened by the recent news reports.

Combined medications and healthy living as outlined above provide the best outcomes as we emphasize in our
program. Further analysis of the study will be conducted when it is available.

Read the full issue of P.E.T. News by clicking the following link. PET News Summer 2011

Please read MI:Aware? I aM Now! and gain an understanding of exactly who is susceptible to heart disease and pass it along to someone you care about.

Click here to read it now!

Dr. John Mandrola writes the following in his blog – Dr. John M

“Sal Khan explains Heart Disease in ten minutes
Posted: 04 Jun 2011 04:25 PM PDT
More than a year ago, I wrote about the amazing educator, Sal Khan. His website, KhanAcademy, has become an educational behemoth. Using colorful and warmly narrated ten-minute YouTube videos, Sal explains–with breathtaking clarity–almost everything you might want or need to know.

He made me grin about re-learning how to do a derivative. He even personally answered an email I sent him on a vexing geometry proof. He tapped back on his iPhone that the proof was unsolvable because there were not enough givens. (That teacher no longer works at my son’s school.) I was so impressed that I clicked on his “donate” button. Now, the Khan Academy, has the backing of Bill and Melinda Gates.

He explains heart disease and heart attacks in just 10:46. How does Sal know all this? How is his explanation of heart disease so accurate? How?

(I realize that 10 min is an eternity on the internet, but for those interested in a solid foundation to understand heart disease, this would be a valuable ten minutes.)

Sal Khan defines heart disease

Each of the 57 million lessons that Sal has delivered were (and still are) free. Everything Sal teaches is free.

Education. Knowledge. For free.

This gives me hope.
JMM”

When John Phillips went to work that summer day, he didn’t realize he was going to become MI Aware. His long time friend had collapsed on the court and needed help. Upon being notified, his team first called 911 and then began Continuous Chest Compression CPR until the EMTs arrived. The EMTs used an AED four times to start his long time friends heart again and he regained consciousness in the ambulance. His friend survived a heart attack with no damage, and the key was the Continuous Chest Compression CPR and John’s quick response.

See the following Video for a how to and why Continous Chest Compression’s only is the new standard for CPR.

http:\\www.youtube.com/user/SarverHeart#

Dr John M

Statins are so misunderstood…
Posted: 29 Aug 2010 06:19 PM PDT
The medical assistant who checked the patient in tells me,

“Dr Mandrola, this guy had coronary artery disease since the 1980′s.  He is 90 years-old now, and his only medicines are that statin and aspirin.” 

One of the more common questions that arises in cardiology is whether a person should take a statin drug. Despite the fact that statins are the most widely studied drug in the history of mankind, there remains widespread misinformation on their use.

Such angst was on full display in the comment section of a recent post from the well known medical blog, KevinMD.  Dr Eric Van de Graaff, a cardiologist and blogger, submitted a very informative and well written piece on the use of statins for the prevention of stroke and heart disease.  (A must read for doctors and patients alike.)

Dr Van De Graaff made many salient points. First, he tells us about the enormity of the science behind the use of statins. No drug has been studied more. He correctly said that in high-risk patients, especially those who have already been diagnosed with blood vessel disease, statins are unequivocally beneficial.

Dr Van De Graaff knows that just saying that statins are scientifically proven to benefit high-risk patients will not be enough for the throngs of nay-sayers, especially those who offer their products to sell.  Thus, he goes on to point out how these drugs were proven successful. In easy to understand language, he explains that the studies (of 120,000 patients) proving statin’s benefits were of the highest scientific rigor: they were prospective, randomized, controlled, and double-blinded.

Even after this fair and balanced piece on statins, the comments illustrate the public’s tremendous misinformation on statins. We read that doctors overly rely on medicines, and we under-emphasize prevention. (They should ask my overweight patients.)  Even a doctor commented, “I’ve read much of the evidence and I am not convinced.” In her psychiatry practice, she had three patients with possible statin side effects, so she is dismissing the data from 120,000.  Yet another doctor who had a unrecognized statin related side effect admonishes us to “consider ramifications of the most important enzyme pathways in our bodies.”  

Confusing the public with medical misinformation really fires me up. And even more inflammatory is that many entrepreneurs use such misinformation for personal gain.

I have written about statins in the past, and as long as the shark-cartlage-for-health-dot-com-like sites continue to spread misinformation, or, the anecdotal reports of this side effect or that side effect speak louder than the truth, I will be motivated to write.

In an effort to spread the truth about prevention of heart disease, I give you this list of statin-facts…
Making good lifestyle choices are the most important means of preventing heart disease. Eating well, sleeping well and exercising daily should be a given. Good doctors will tell you this, but they shouldn’t need to.
Drugs, procedures or surgery should never replace good lifestyle choices. Taking a statin to counteract cheetos is utter nonsense.
Statin drugs lower cholesterol levels, but this is not likely the primary mechanism of cardiovascular benefit. They are vascular anti-inflammatory agents that work at the blood vessel wall. 
In patient’s with high a risk of heart disease (those with risk-factors like genetic predisposition, diabetes, high blood pressure or smoking), or in patients who have had a vascular event (stent, heart attack or stroke), statins are scientifically proven to be beneficial. The science behind this is second to none.
Even though science proves the benefit of statins in the secondary prevention of vascular events, it does not mean they are devoid of adverse effects. It just means that the side effects are greatly outweighed by the reduction of events (in 120,000 patients.) 
These same trials showed that the side effects of statins were very similar to those of placebo.  Do the nay-sayers tell patients this?
Adverse effects of statins are rarely if ever life-threatening. However, the disease which statins prevent, heart attack and stroke, are definitely life-threatening.
Statin side effects are real, and they are clearly higher than what is reported in the literature. Sometimes they can be mitigated by changing to a different statin, but more often than not, they are a class effect, and these patients cannot take them.
Whether statins reduce CV risk in patients whose only risk factor is a high cholesterol is not clear. Low risk patients have such low event rates, that is hard to show a benefit of any therapy. Statin-enlightened doctors know this. Patients could ask, “Doc, high cholesterol is my only risk, do you really think a statin will alter my long-term outlook?”
If changes in one’s well being are noted after starting a statin, the drug should be considered as a culprit. This is why there is a doctor-patient relationship, and why doctors should have the time needed to listen to the patient’s story.
When reading about your health consider potential conflicts of interest. We all know about big pharma’s conflicts: they make more money if they sell more statins. To me, such conflicts are self-evident and understood. However, the entrepreneurial nay-sayers are also conflicted. Bashing science-based medicine is a fertile field of business. The statin-bashers will frequently have a newsletter, book, diet or supplement to sell you. Conflicts. Be aware.
Doctors do not financially benefit from prescribing statins. We can’t even use pens with industry logos anymore. Doctors recommend statins because we know that the small risk of an adverse effect is out-weighed by the proven benefit. And as a rule, the higher the risk of an event the more the benefit. 
I believe in patient choice. Patients can choose to forego the benefit of statins, just like they can forego any medical therapy. 
Doctors wish there was no need for drugs.  We wish you hadn’t had a heart attack, but since your endothelium has proven to be susceptible, our goal is to prevent another event.  In addition to good lifestyle choices, a statin drug will clearly decrease your risk.

Sore muscles are unfortunate, but not as much as a heart attack or stroke.

JMM

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Google Inc., 20 West Kinzie, Chicago IL USA 60610

GOALS FOR REVERSAL

STOP SMOKING

FOOD: PROTEIN ,VEGGIES, FRUIT

• VERY LOW FAT
• LOW CHOLESTEROL

LOW CARBOHYDRATE

LEAN BODY WEIGHT

CHOLESTEROL MEDICATIONS

• STATINS
• NIACIN
• FIBRATES

CHOLESTEROL GOALS

TOTAL CHOLESTEROL-<140

TRIGLYCERIDES-<90

LDL CHOLESTEROL-<70

HDL CHOLESTEROL->45

CONTROLLED BLOOD PRESSURE
MODERATE EXERCISE
DE-STRESS

Visit the following link for more info:  http://www.uth.tmc.edu/pet/patients/preventing-goals-of-reversal-therapy.htm

Arm, chest, neck, and back pain, discomfort or an uncomfortable feeling are all symptoms of a heart attack.  As is an overwhelming feeling of impending doom.  That last symptom is to bizarre, as the 2nd anniversary of my first symptoms is fast approaching.

I was racing at the time and had finished my solo efforts and was caught by the group.  Once dropped from the main group, it was just another routine training ride for me.  However, I can’t help but remember how vivid the calling was for me to consider getting off the bike and getting into the support vehicle.  I can’t help but remember my questioning whether I’d be able to make it to the finish line with only 12 miles to go.  After all, it was just a 26 mile training ride by myself  to return.

When I got back to the car, I was slightly weak and just a bit perplexed as to why I was feeling so lousy.  I ate something and had a drink only to get that upset stomach feeling.  You know the kind which is similar to, “heart burn.”  Turns out, that burn was not a burn at all.  It was a neurological response and the pain was coming from the Apex of my heart where my LAD (Left Anterior Descending) coronary artery was 90% blocked or more.

Once the pain in my stomach as I called it started, I had a friend drive me home.   At that time, I did the usual post-race clean up  and layed down after researching heat stroke and exhaustion on the internet.  So it wasn’t that I completely ignored the symptoms or warning signs, my wife and I mis-self-diagnosed the problem.

The arm pain or burning sensation between my elbow and armpit in both arms, was not the old symptom we were always told to look out for in 8th grade health class.  Nor was the pain in my chest, the lower thorax, not the upper chest region.

In any event, I’m lucky to be here writing about the warning signs and urge you to familiarize yourself with them.