Exercise & the heart

Book Review: Haywire Heart

April 5, 2017 By Larry Creswell, MD Leave a Comment

Check out the recently published “The Haywire Heart” by Chris Case, John Mandrola, MD, and Lennard Zinn. The book is available at Amazon and other outlets.

You may recall that Case, Mandrola, and Zinn authored an article in VeloNews, entitled “Cycling to Extremes: Are endurance athletes hurting their hearts by repeatedly pushing beyond what is normal?” This was a terrific read. I wrote a previous blog post sharing my thoughts about the article and about the issue of arrhythmias and endurance sport, more generally. Their article generated much discussion in the cycling and broader endurance sports communities and the interest of readers served as the motivation for their new book.

This is a book about electrical problems in the heart–the various arrhythmias. Case, Mandrola, and Zinn are in a unique position to bring this topic to life because each has dealt personally with some form of arrhythmia. And as long time cyclists (and perhaps with some triathlon experience as well), they’re able fashion the discussion to the avid endurance athlete. From the medical perspective, the field of arrhythmias is rather complicated, both in terms of the underlying mechanisms of disease and the evaluation and treatment of affected patients, but here the authors have found a writing style that is captivating and accessible to the non-medical reader, while retaining much medical detail that will be of interest. I give them credit because this is hard to do!

I love the title. With an arrhythmia, the heart is truly “haywire.” Ignore the line on the cover, though, about “How too much exercise can kill you.” That’s unlikely to happen and there’s little in the book about that particular issue. Instead, focus on “what you can do to protect your heart.” That’s where the value lies here.

The book is organized into 9 chapters. In Chapters 1-3, the authors describe in detail how the normal heart works, outline how the heart adapts over time to endurance exercise, and introduce the medical aspects of heart attack and arrhythmias, especially for the endurance athlete. These sections are well-illustrated and are a great primer for any athlete interested in learning more about the heart.

Chapters 4-6 focus on the evidence of a link between long-time endurance exercise and arrhythmias, what to look for in yourself, and what it’s like to receive the diagnosis of an arrhythmia. Here, the authors speak from personal experience and their observations and advice are valuable.

Chapter 7 deals with the issue of exercise addiction. We know that exercise is generally healthy, but most of the benefits of exercise accrue with the first few hours per week. Why, then, do athletes exercise more? When does one become addicted? What are the implications? This is an interesting and pertinent discussion and might provoke some warranted introspection.

Chapter 8 covers the various treatment options for athletes with various arrhythmia problems. For athletes who don’t have trouble with arrhythmias, the discussion is educational in a broad sense. For those who do have arrhthymias, though, there is ample detail here to become educated and be better engaged with your doctor(s) as you sort out the best treatment for you.

Finally, in Chapter 9, the authors wrap up with their “takeaway” on how we might prevent arrhythmia problems.

One of my favorite aspects of the book is the inclusion of Case Studies sprinkled throughout the text, where the authors illustrate their points in a side bar with the personal account of an athlete. These stories bring us the human side of arrhythmias and show how difficult these problems can sometimes be.

This book is for….

the athlete with an arrhythmia problem. There’s a lot of familiar territory here as well as the opportunity to learn more. An educated patient is the ideal patient.
the athlete with simply an interest in the heart. I can’t think of a better resource to become educated about the workings of the heart, particularly as they relate to the endurance athlete.
the athlete (or the athlete’s spouse or parent) who’s afraid of causing harm to the heart through exercise. Be forewarned and be vigilant.

Related Posts:

Heart to Start, by James Beckerman, MD
The Exercise Cure, by Jordan Metzl, MD
Cardiac Athletes, by Lars Andrews

Returning to Exercise (and Training) After Heart Surgery

May 1, 2016 By Larry Creswell, MD 23 Comments

I’ve had a bunch of requests for a blog post on getting back to exercise or training after heart surgery. These requests usually come from: 1) athletes who are contemplating an upcoming operation and are already worried about if/when/whether they’ll be able to get back to exercise afterwards or 2) athletes who’ve recently had successful operations and are looking to become active once again, but are looking for reassurance that it’s safe to do so. I marvel every time I see an athlete patient get back to exercise after heart surgery, so I’m always encouraged by these inquiries.

For today’s discussion, let’s confine ourselves to what I call “conventional” heart surgery—the whole collection of heart operations that use a chest incision, with splitting of the breast bone (sternum), and make use of the heart-lung machine for cardiopulmonary bypass during the procedure. We’ll save for another day those procedures that are “less invasive” in some way, use some other incision or approach, and those that don’t make use of the heart-lung machine. As examples, I’m talking about common operations like coronary artery bypass grafting (CABG) or heart valve repair or replacement.

At the outset, we need to have a big disclaimer. Athlete patients are all different. Their operations are different, too—even when we’re talking about just the commonly performed operations. And because athletes and operations are all different, I can only generalize here.

If you’re an athlete patient, please use this post to become educated about some of the issues and help gather your thoughts for conversations with your own doctor(s). This is the only way to settle on plans that are right for you.

Athletes in this situation should remember that there are very real issues with the safety of exercise. My best advice is to take things slowly and consult with your doctor(s) frequently.

Athletes and Operations are Unique

Athletes who need heart operations can be different in many ways. Some need operation for congenital, or inherited, conditions they’ve had since birth (eg, atrial septal defect [ASD]). Others need operation for acquired conditions that take many years to develop (eg, coronary artery disease, aortic aneurysm). In still others, an emergency operation may be needed for some sort of acute problem (eg, aortic dissection).

In many cases, athletes will have conditions where the heart function is preserved, but some will have conditions where the heart has suffered some sort of damage, and become weakened, over time. Some athletes will be healthy except for their heart condition and others will have other medical conditions that affect not only the operation, but also the recovery.

Finally, athletes will come with all sorts of sports backgrounds and all sorts of future goals. Some will be young and others will be old. Some will be recreational athletes, some will be exercisers, and some will be competitive athletes. Some will have had high fitness levels before operation, and others will not. The demands of the various sports are different, too. Some have highly “dynamic” nature (eg, running). Others have a high “static” nature (eg, weightlifting).

Heart operations are different, too. In some cases, operations can be curative. In others, the operation might better be thought of as “mending a broken heart.” Moreover, in some cases the underlying heart condition can take a long time to improve, even if operation is successful.

For all of these reasons, there can be no “one-size-fits-all” prescription for return to activity, exercise, and training. Instead, the prescription must be individualized.

Healing Up

Things need to get healed up after operation. This should be obvious.

The surgical wounds need to heal after surgery. The skin incision ordinarily heals very quickly. With either skin staples or absorbable sutures beneath the skin, the surgical wound usually seals in the first few days. It’s worth paying attention to instructions for showering, bathing, and swimming. Any infection of the surgical wound can be a major setback to healing. Pay attention to instructions to watch for swelling, redness, or drainage that might be signs of infection.

Deeper, the breast bone (sternum) is like any other broken bone. We wire the sternum back together and in most cases, the bone knits back together just like any other broken bone. This is a process that takes many weeks, but we often say that the bone regains about 75% of its strength in the first month, so long as healing proceeds correctly. During the first month, we generally restrict activities that place stress on the sternum as it heals. We ask patients to avoid pushing, pulling, reaching, or even just carrying heavy objects (more than 10 pounds). Many surgeons also restrict driving for the first month. All of these activity restrictions are important because exercise early after operation must usually involve the lower body, rather than the upper body.

Deeper still, the heart itself must heal up. Regardless of the exact operation, the handiwork here usually involves needle and thread. The tissues are sewn together or new materials (eg, heart valves) are sewn into the heart. Although the tissues or devices are fixed securely in place, it takes many weeks or even months for the affected tissues to heal completely. Your surgeon will be in the best position to comment on the expected period of time that will be needed for healing and to offer advice about any longer term risks to the affected tissues, devices, or prosthetics used that might come with various forms of exercise.

One final point is that healing may be impaired in some patients. Conditions such as diabetes, a suppressed immune system (eg, from illness or medications such as steroids), or even just poor nutrition before operation can delay healing substantially.

Is the heart mended? Or good as new? Does the disease continue even after the operation?

Thinking ahead to physical activity after operation, one very important consideration is: how healthy is the heart now? Have we cured the problem? Or have we mended the problem? Or, perhaps, have we introduced some new problem?

The important question to consider is: Does my current heart situation place me at increased risk for a future problem? And, if so, how big is that risk?

As one example, sometimes an athlete will need operation to correct an atrial septal defect (ASD), an inherited condition. If this condition is found before any damage has occurred to the heart or lungs, operation is curative and athletes can generally return to any form of sports activities after they’ve healed up.

As another example, sometimes an athlete will need coronary artery bypass surgery after a heart attack, or acute myocardial infarction (MI), in medical terms. The “plumbing” can be fixed with operation so that blood flow is restored past all (or most) of the blockages in the coronary arteries. It turns out, though, that it can take up to 2 years for the ruptured plaque that caused the MI to become stabilized. During that time, the best advice might be to limit strenuous exercise because of the increased risk of repeat MI.

In yet another example, sometimes an athlete will need operation for repair of an aortic aneurysm. Most often, a portion of the enlarged aorta is “repaired” by replacing the blood vessel with a synthetic, fabric substitute. After successful operation, though, there may still be mild enlargement of the remaining aorta that deserves surveillance over time for possible enlargement. Sports activities with a high “static” component (eg, weightlifting), where there can be large increases in the blood pressure, may not be advisable, for fear of accelerating aortic enlargement over time.

These are just 3 examples. The scenarios are virtually endless.

New Medications

For some athletes, things can be so “normal” after heart surgery that no new medications are needed. Sometimes, medications that were required before the operation are no longer needed. These athletes are fortunate.

For other athletes, though, new medications can be needed either because of the underlying heart condition or because of new hardware that’s been added. As an example, aspirin, beta blockers, and statins are often recommended for athletes who’ve had operation for coronary artery disease. Each of these medications will have implications for the athlete. As another example, blood thinners like warfarin (Coumadin) might be prescribed for an athlete with a mechanical heart valve. The anticoagulants also bring a potential risk of unwanted, serious bleeding in the event of bodily injury. This is a factor which must be weighed when settling on what types of physical activity are safe.

Cardiac Rehabilitation

Cardiac rehabilitation, or “rehab” for short, is a supervised program that includes medical evaluation, development of a physical activity program specific for the patient, educational services, and individual and group exercise where the vital signs and EKG can be monitored. The structure of these programs may vary by location, but will usually involve both an inpatient phase and an outpatient phase.

At many heart surgery programs, the inpatient phase of cardiac rehab begins within the first couple days after operation, with both educational and exercise components. There are usually educational offerings about nutrition, medications, lifestyle modifications, and community resources. There is also an exercise component that is tailored to the patient, usually involving walking at first, where there is close monitoring of the vital signs, the heart rhythm, and the oxygen level in the blood stream. It’s important early after operation, together with the patient and family, to establish expectations and goals about physical activity.

Cardiac rehab continues with an outpatient phase, where patients can enroll in a monitored exercise program, often in a group setting, with several sessions per week. Athletes may sometimes fail to see the value in such a program, but these programs can actually provide some much needed structure to the early return to exercise. Most importantly, these programs can provide confidence for the athlete that once they leave a structured setting, things will still be okay with their heart and safety during exercise. I’d recommend a full cardiac rehab program for all athletes who are looking to return to exercise after operation.

For most patients, walking is the most appropriate exercise early after operation, with an emphasis on moderate exertion and increasing duration.

Support

Having a good support system is important for any patient after heart surgery. It’s particularly true for the athlete who is returning to a formal exercise or training program after heart surgery. You can envision this support system as having a set of layers.

Closest to home, athletes will benefit from a family that helps to encourage a return to physical activity and works to make this possible. Family is usually the best support for ensuring continued good nutrition, ensuring restful sleep (including naps), and seeing to other various needs after the patient returns home from the hospital.

When it comes to returning to structured, independent exercise, I believe that a group setting is often best. We all know that it’s more motivating when we have friends to meet for the morning run or ride. In the case of athletes with recent heart surgery, it’s also reassuring for the athlete to know that company is nearby if some sort of medical problem crops up during an exercise session. Even if this possibility is unlikely, a group of fellow exercisers can provide some needed confidence.

Being able to share experiences with other athletes who’ve had similar surgery can often be helpful, even if those athletes aren’t close to home. There are a variety of support groups with an online presence, but two of my favorites are the Ironheart Foundation and Cardiac Athletes. Both offer an opportunity to network with similar athletes, learn from their experiences, and also have a forum to “give back.” You’re not alone. Many other athlete patients are dealing with the same or very similar situations.

Lastly, for athletes who are looking for some good reading material, one good resource is a book entitled “Heart to Start,” by cardiologist James Beckerman, MD. I’ve written a review about this book previously here at the blog. The book describes a gradual, structured path to resuming aerobic exercise and conditioning once cardiac rehab is completed.

Follow-up

It’s wise for athlete patients to put together a robust framework of medical support as they return to physical activity after heart surgery. Your “team” should include at least your heart surgeon, your cardiologist, and your primary care provider. At the beginning, there might also be a nutritionist, your cardiac rehab specialist, or physical therapist, as well. Perhaps you can think of other important team members as well.

Continuous dialog with your team is essential. Only you will be able to describe your goals and ambitions and ask for feedback about the advisability and safety issues. Don’t assume that your doctor(s) will understand what it means to train for the masters national swimming championship or a marathon or a 70.3 triathlon. If you envision several hours of aerobic exercise as well as strength training each weak, be prepared to describe this in detail, with expected exertion levels or heart rates, so that your doctor(s) can know exactly what you have in mind. Don’t hold back.

Athletes should arrange for periodic visits with their doctor(s) so that they can discuss their plans for physical activity, share their experiences, both good and bad, develop plans, agree on any restrictions, and monitor progress. This is good advice for any athlete, but particularly good advice for athletes who have had heart surgery.

In thinking about what sorts of exercise or training is safe for their athlete patients, doctors don’t always have a bunch of accumulated scientific evidence to rely upon. I’ve written previously here at the blog about consensus recommendations about the safety of sports for young, competitive athletes with various cardiac conditions. These recommendations weren’t developed specifically for adult, recreational athletes after heart surgery, but they may provide a starting point for discussion. Often, though, doctors must rely upon judgment and personal experience with similar patients.

Warning signs of a problem

I’ve talked previously about 5 important warning signs of potential heart problems: chest pain/discomfort, unusual shortness of breath, palpitations, blacking out (or nearly so), and unusual fatigue. Athletes should be vigilant about these general warning signs and report them to their doctor(s).

There may also be additional warning signs to watch for, that are very specific to the type of surgery an athlete has had. Some examples would include:

For those with a mechanical heart valve, stroke symptoms (temporary or permanent loss of sensation or muscle weakness) would be important
For those with coronary artery disease, return of angina symptoms (chest pain/discomfort) would be important
For those with aortic aneurysms, return of chest, back, or abdominal pain would be important
For those with arrhythmias, return of an irregular heartbeat or palpitations would be important.

Sometime in the first few weeks after operation, you should have a discussion with your doctor(s) about any specific warning signs that are most important for you. And then you should be vigilant.

Summary

Let me summarize the important points:

Each athlete’s situation will be different
Whatever the approach to returning to activity, pay attention to getting healed up, as a first priority
Participate in a cardiac rehab program
Consider your “new,” current heart situation as you make plans about the safety of exercise
Rely on your support network as you return to physical activity
Assemble a medical “team” to help as you return to physical activity
Make a list and be vigilant about warning signs that are specific to your circumstance

Related Posts:

In the Medical News: Does Heart Function Suffer in Long-term Endurance Athletes?

April 17, 2016 By Larry Creswell, MD 18 Comments

Background

Moderate amounts of exercise produce a multitude of health benefits. Both the American Heart Association (AHA) and World Health Association (WHO) now recommend 150 min per week of moderate intensity exercise for adults.

Some recent observations, though, have raised the question: when it comes to exercise, can there be too much of a good thing? And, more specifically, can too much exercise somehow be harmful to the heart. With the increased popularity of adult recreational and competitive sports–particularly in cycling, running, and triathlon–there is a growing number of adults who are pursuing exercise far in excess of the AHA and WHO recommendations. The questions surrounding the issue of “too much exercise” are very pertinent.

A few recent articles in the popular press summarize some of the findings and frame the debate:

Can Too Much Extreme Exercise Damage Your Heart?–at Cleveland Clinic online
Can Too Much Exercise Harm the Heart?–by Gretchen Reynolds at NY Times Well Blog
Is Too Much Exercise BAD for the Heart?–by Anna Hodgekiss at The Daily Mail
Extreme Exercise and the Heart–by Lisa Rosenbaum at The New Yorker

The worrisome observations have generally been made in small numbers of symptomatic athletes, in groups of athletes whose athletic history–or “dose” of exercise is poorly characterized, or in studies that were designed for some purpose other than determining the effects of “too much exercise” on the heart.

I’ve said previously that these observations deserve our attention, but that we really need more targeted investigation into this issue. In a study just released online (ahead of print) in the medical journal, Circulation, Philipp Bohm and colleagues from the Institute of Sports and Preventive Medicine at Saarland University in Germany bring us an important new look at “extreme” exercisers.

The Study

This new study focuses on a group of 33 healthy, male, Caucasian competitive elite master endurance athletes. This group of athletes was selected so that it included only athletes with a 10+ year continuous training history of 10+ hours per week; the average training was 16.7 hours per week and the average training history was 29 +/- 8 years. These athletes had an average age of 47 years (range, 30-60 years). This group of athletes included:

Sixteen were former elite professional athletes
One Ironman world champion and several 2nd and 3rd place finishers
The world record holder at the long distance triathlon
A 2nd ranked cyclist of the Vuelta a Espana (Tour of Spain)
Six Olympic athletes in the sports of triathlon and rowing
A former winner of the Munich Marathon.

A control group consisted of 33 healthy Caucasian men who were pair-matched for age, height, and weight. This control group was selected to include only individuals who exercised <3 hours per week.

All of the subjects underwent a comprehensive evaluation that included:

History and physical examination (to exclude any athlete with a history of overt heart disease, high blood pressure, smoking history, or other risk factor for heart disease)
Resting EKG
Cardiopulmonary exercise testing
Echocardiography, including tissue-Doppler imaging and speckle tracking
Contrast-enhanced cardiovascular magnetic resonance imaging (CMR).

Interestingly, none of the athletes presented with, or reported a history of, atrial fibrillation.

There were several unsurprising, and expected differences between the athletes and the controls. First, the resting heart rate (HR) for the athletes (48 +/- 7 beats per minute) was slower than for the controls (65 +/- 11 beats per minute). Second, the size of the athletes’ hearts was significantly greater. The left ventricular (LV) mass for the athletes’ hearts (188 +/- 26 g) was significantly greater than the controls (124 +/- 23 g). Similarly, the right ventricular (RV) mass for the athletes’ hearts (70 +/- 13 g) was significantly greater than the controls (49 +/- 11 g). Among the 33 athletes, 22 met a traditional definition of “athlete’s heart,” with a heart volume of 13+ mL/kg of body weight. As expected, the VO2 max of the athletes (60 +/-5 ml/kg/min) was significantly greater than controls (37 +/- 6 ml/kg/min).

The important results of the study were those that showed no difference between the athletes and the controls. With echocardiography, there was no difference between athletes and controls in LV longitudinal strain or RV longitudinal strain–measures of the strength of contraction. Using CMR, there was no difference between athletes and controls in LV ejection fraction (EF) or RV EF–again, measures of the strength of contraction. One athlete (3%) had a LV EF slightly less than normal, at 45%. No athletes or control subjects had abnormalities of the RV that could be suggestive of the potentially life-threatening problem of arrhythmogenic right ventricular cardiomyopathy (ARVC). One athlete (3%) had late gadolinium enhancement (LGE) on CMR that suggested previous, asymptomatic inflammation of the pericardium, the sac in which the heart sits. LGE analysis showed no evidence of unusual fibrosis or scarring in either athletes or controls.

My Thoughts

Kudos to the investigators here. The study is apparently self-funded. It’s expensive to perform this kind of testing; in the United States, the costs of this study would easily run into the many hundreds of thousands of dollars. Kudos, too, to the editors at Circulation. There is a tremendous bias against publishing so-called “negative” studies, where no important differences are found between study and control groups. Many “negative” studies are left on the editing room floor–and we never hear about them.

This is an important study because it is the first to gather and study a group of long-term endurance athletes with a substantial, and defined, training load over an extended period of time. The results deserve our attention. At nearly 17 hours per week of exercise or training, these athletes obviously far exceeded the contemporary recommendations for 150 minutes of moderate exercise per week. Just doing some quick math, the average cumulative exercise “dose” is more than 25,000 hours. As I’ve said many times before, it’s worth asking the question if such an exercise pattern can be harmful to the heart over the long term. This is a terrific group of athletes to study in order to help answer that question.

We must keep in mind that, with just 33 athletes, this is a small study. With only 33 athletes, it’s obviously possible to miss something that would be found in the 34th athlete. We must also keep in mind that the study only involves male athletes. Female athletes are not immune from heart problems and deserve study, too.

It is a striking finding that no athlete was found to have atrial fibrillation–either now, or in the past. Moreover, no athletes experienced arrhythmias during the cardiopulmonary exercise test. A number of previous studies have reported a 2- to 5-fold increase in atrial arrhythmias among long-term endurance athletes. Like the current study, all of those previous studies have involved small number of athletes. None, though, have focused on athletes like these, with such extensive exercise and training histories. In my opinion, endurance athletes broadly can take some comfort from the findings of this new study with regard to the potential risk of atrial arrhythmias.

It’s noteworthy that the LV and RV function of the athletes was no different than the controls. One athlete had mildly depressed LV function, for reasons that are not clear. In short, though, the study found no evidence of cardiac damage–at least, in terms of the pumping function–that accrued over the long term. We know that there is some depression of LV and RV function immediately after an intense bout of exercise (eg, marathon, long-distance triathlon, long-distance cycling event), but we also know that these changes resolve within days to weeks afterward. The current study argues against the hypothesis that repeated episodes of intense exercise (ie, many marathons or triathlons over a lifetime) might result in a decrease in LV or RV function. Again, this is encouraging news for endurance athletes.

Finally, the CMR and LGE results are important. Aside from the 1 athlete with possible previous pericarditis, there were no worrisome findings of fibrosis or scarring that might be attributable to injury from repeated episodes of intense, strenuous exercise. These LGE findings are at odds with some observations of unexplained fibrosis in other cohorts of long-time runners, even if the consequences of such findings remain uncertain. This area of investigation deserves further attention. For now, I’d say that long-time participation in endurance sports does not necessarily result in unexplained fibrosis in the heart.

Related Posts:

Interesting Research Studies from the ACC’16 Meeting

April 13, 2016 By Larry Creswell, MD Leave a Comment

This year’s annual meeting of the American College of Cardiology (ACC) was held recently in Chicago. This year I was able to attend the meeting, so I can share what I learned, first-hand. I became a member of ACC at the meeting and I also had the opportunity to be a co-author of a poster presentation on triathlete fatalities that I will describe below. Like I’ve done for the past couple years, I’ll share here a round-up of some of the sports cardiology studies that caught my eye. In the months ahead, we can look forward to seeing the published reports. Here are my Top 5:

1. Fatalities in United States triathlons: An expanded profile. I joined with Kevin Harris and colleagues from the Minneapolis Heart Institute to report on 106 fatalities in American triathlons since 1985. The average age of victims was 47 years–approximately 12 years older, on average, than participants as a whole. The majority of victims (85%) were male. The approximate fatality rate was 1.52 per 100,000 participants, with a rate of 2.05 per 100,000 participants in men and 0.71 per 100,000 participants for women. The majority of deaths (71%) occurred during the swim portion of events, with smaller numbers during the bike or run segments, or immediately after the race. Trauma was the most common cause of death during the bike segment. The vast majority of other deaths involved cardiac arrest at the race venue. Autopsy information was collected for 41 victims. Among those autopsies, significant cardiovascular disease (coronary artery disease, hypertrophic or dilated cardiomyopathy, coronary artery anomaly, Wolfe-Parkinson-White syndrome, arrhythmogenic right ventricular cardiomyopathy [ARVC]) that caused or contributed to death was found in 55%.

My take: This is the most comprehensive look yet at triathlon fatalities. The findings remind us of the critical importance of safety planning and execution on the part of event organizers during the swim portion of events. The preponderance of deaths among men, particularly those of middle age, and the preponderance of cardiovascular disease among victims suggests that targeted cardiac screening might be helpful for reducing the number of fatalities. We’re working hard on preparing a full-length article. I’ll report back when it’s published.

2. Automated cardiac arrest detection and alerting system using a smartphone and standard Bluetooth chest strap heart rate monitor during exercise: The “Parachute” app. Nicola Gaibazzi and colleagues from University Hospital in Padua, Italy report on their initial experience–essentially, a feasibility study–with a smartphone app/Bluetooth heart rate strap that can detect cardiac arrest and automatically alert emergency response services by SMS, reporting a GPS location for the incapacitated athlete. The authors make special note that no special hardware is needed since many runners and cyclists likely already carry a cell phone. The investigators report that the system has been tested in 10 athletes for a total of 32 hours of running and 52 hours of cycling. During that period, there were no “false alarms,” where an emergency message was sent unnecessarily. The system has also been tested in the laboratory with equipment that simulates a fatal arrhythmia and the system’s arrhythmia detection system was 100% effective in recognizing ventricular fibrillation (VF).

My take: As somebody who often runs or cycles alone, there is obvious appeal. Additional testing, particularly in the field, will be needed to sort out the issue of possible “false alarms” and to be certain the arrhythmia detection algorithm is truly robust. Given the pace of technological development related to heart rate monitors, I suspect that we will see more systems like this become commercially available in the near term. I wonder, though, about what impact such devices/systems might have on the survivability of unwitnessed cardiac arrest, where the importance of prompt CPR and defibrillation are known to be essential.

3. A novel pre-participation questionnaire for young competitive athletes. Despite years of study and a considerable literature based on expert opinion, there is still no consensus in this country about whether–and how to–screen young competitive athletes for hidden, unsuspected heart conditions that place such athletes at risk for sudden cardiac death (SCD) during sports activities. The American Heart Association (AHA) currently recommends a 12-item questionnaire that combines medical history and physical examination (PE) findings. The European Society of Cardiology (ESC) currently recommends a medical history, PE, and a resting ECG. In this study by James McKinney and colleagues from the University of British Columbia, one group of 686 young (age 12-35 years) athletes underwent screening with the AHA 12-item questionnaire, PE, and ECG. Another group of 674 young athletes underwent screening with a new, novel questionnaire and an ECG, but did not have a PE. In the first group, 59 athletes (8.6%) required follow-up testing because of abnormal findings during the screening process; 5 (8.9%, 5/59) of these athletes were actually found to have significant heart conditions. In the second group, 31 athletes (4.6%) required follow-up testing because of abnormal findings during the screening process; 6 (19.4%, 6/31) of these athletes were actually found to have significant heart conditions. So, perhaps surprisingly, the positive predictive value of the new approach (that omitted a PE) was significantly and considerably better. By reducing the false-positive rate of the screening process, this new approach might be potentially more efficient, less costly, and cause less disruption in the sports routine for athletes while additional testing is obtained.

My take: False positives during a screening process for rare conditions can be very costly in terms of additional testing and time lost from sports participation, so strategies to reduce the frequency of false-positives would be welcome. The study points out what we’re taught early on in medical school: 90% of diagnosis can be derived from a conversation with the patient!

4. Electrocardiogram utilization in the marathon medical tent. Jennifer Michaud Finch and colleagues from Massachusetts General Hospital and Northwestern University report on the utilization rate and clinical impact of ECG in the medical tent of the 2015 Chicago Marathon. There were 37,000 finishers. A total of 12 ECGs were performed: 5 for chest pain, 2 for pre-syncope, 1 for exertional syncope, and 1 for post-exertional syncope. One case of ST segment elevation and T wave changes, suggestive of acute coronary syndrome, was identified and the athlete was transferred to the hospital. Much more commonly, though, the ECG was useful for reducing the concern for an acute cardiovascular problem. Medical tent providers rated the clinical value of the medical tent ECG as an 8 on a 10-point scale. The authors concluded that, although performed very infrequently, medical tent ECGs were very helpful in making decisions about athlete diagnosis and triage.

My take: It appears that the ability to perform an ECG in the medical tent for a large, urban marathon is important. Obviously, expert interpretation is needed in order to make correct decisions about diagnosis, on-site treatment, and potential transfer to the hospital. It is important to remember, though, that the ECG was used for only 1 per 3,080 runners. For smaller races, then, which may have less sophisticated (or no) medical tents, consideration might be given for triage to the hospital emergency room in the unusual case where an ECG is thought to be needed.

5. The impact of age and completion of a moderate distance running race on cardiac function: Results from P.E.A.C.H. (Profiling the Effects of Aging on Exercise-induced CHanges in Cardiac Mechanics). We know from previous reports that there is release of cardiac enzymes into the blood stream as well as a transient decrease in the pumping strength of both ventricles after long endurance events such as triathlon, long-distance cycling, or long-distance running. This phenomenon is sometimes referred to as “cardiac fatigue.” Much less information, though, has been reported about potential adverse cardiac outcomes after moderate distance running races, despite the huge popularity and participation in such events. Jonathan Kim and colleagues from Emory University report on a group of 73 athletes who participated in the 2015 Peachtree 10k running race in Atlanta, Georgia. Each athlete underwent a limited echocardiogram 24-48 hours before the race and then again immediately (within 5 minutes of finish) after the race. There were no decreases in the important echocardiographic indices of cardiac function after the race, for either the left or the right ventricle.

My take: This is an intriguing finding. One might wonder what is so different about a 10k race, compared to a half marathon for instance. We do know that, with long-distance events, cardiac enzymes return to normal and changes in cardiac function detected by echocardiogram return to normal within days after the event. The long-term consequences, if any, remain unclear. Some have theorized that repeated “episodes” of transient cardiac damage, arising from participation in many such events over a lifetime, might result in harm to the heart. The findings of the current study suggest that participation in shorter events may not carry the same long-term risk.

2. Interesting Research Studies from the ACC’14 Meeting

Japan and Triathlon Fatalities

February 25, 2016 By Larry Creswell, MD 2 Comments

I’ve recently returned from a trip to Tokyo, Japan, where I was the guest of the Japan Triathlon Union (JTU). The occasion was their organization’s 5th Annual Forum, which this year was devoted to the issue of triathlon race safety.

I appreciate the kind invitation from Mr. Otsuka and Mr. Nakayama, the help of JTU’s Kenta Kodama with the travel arrangements, and the tremendous help with translation from Ms. Tomoko Wada. My hosts were gracious in every way. I must also thank the kind folks at USA Triathlon (USAT)–Terri Waters and Kathy Matejka, for help with gathering some updated information to present in Japan, and USAT President Barry Siff for making the necessary connections with JTU.

As readers here will know, I’ve had an interest in triathlon-related fatalities and the broader issue of sudden cardiac death among endurance athletes. I had the opportunity to lead a recent USAT effort to learn more about triathlon-related fatalities and our work resulted in a 2012 report entitled “Fatality Incidents Study.” As I’ve said before, this report is good reading for athletes and event organizers who are looking for recommendations about how to race safely and conduct events with athlete safety as a first priority.

Sadly, there were 6 triathlon-related fatalities in Japan in 2015, the most ever in a single year there. Dr. Ryoji Kasanami, the Chairman of the JTU’s Medical Committee, had become familiar with our work here in the USA and was interested in learning how our findings might help JTU with better safety planning, on the parts of both athletes and event organizers.

I gave a talk at the Forum where I outlined the USAT experience with fatalities since 2003. In large part, the information is summarized in my previous blog post, Triathlon Fatalities: 2013 in review. I was able to include some updates through the 2015 season, but the central themes were the same now as then:

There is variation in the fatality rate from year to year, with an overall fatality rate of ~1 per 70,000 participants
Most fatalities occur during the swim portion of events
Most victims are male
Fatalities are most common among middle-aged athletes
There have been no fatalities among elite (professional) athletes
Among victims, there is a wide range in athlete experience and ability
There is a small number of trauma-related fatalities, arising from bicycle crashes
Among non-traumatic fatalities, the vast majority suffered cardiac arrest at the race venue
Available autopsy information for non-traumatic fatalities has shown heart abnormalities in the majority

Dr. Kevin Harris, from the Minneapolis Heart Institute, and I will be presenting an abstract at the upcoming American College of Cardiology meeting in April in Chicago on this topic. We’ll be sharing consolidated information about 106 fatalities, including the autopsy findings from 41 of the non-traumatic fatalities. I’ll report back here at the blog with an update in April.

Dr. Kasanami shared information about the Japanese experience with 37 fatalities over the past 3 decades. There were many similarities to the experience in the USA:

Some years were “safer” than others
Most fatalities occurred during the swim portion of events
Most victims were male
Fatalities were most common among middle-aged athletes
There have been no fatalities among elite athletes
There were no fatalities in young athletes

There were also some notable differences:

There were no fatalities during the bike portion
Autopsy was seldom performed in the victims

Interestingly, the bike course is always closed to vehicular traffic during triathlons in Japan, and this might obviously have an impact on the number of crashes and trauma-related fatalities. One interesting anecdote shared by a pathologist attendee related to the finding of inner ear bleeding (hemorrhage) in 2 victims. I’m not sure about the significance of this observation.

I’m intrigued by the many similarities of the Japanese experience with race-related fatalities. I also know from preliminary discussions with officials at Triathlon Australia that the experience in Australia is similar as well. I suspect that the causes of cardiac arrest in participating athletes are common broadly, and are more dependent on simply the human condition rather than race-related factors that might be specific to one region or another (eg, race safety or technical rules, approach to medical care on site, warm-up, etc.).

I’ll mention here that the Medical Committee of the International Triathlon Union (ITU) is very interested in this issue, particularly as it relates to elite athletes. I understand that efforts are being made to implement the requirement for mandatory periodic health evaluations, including EKG screening, for youth, U23, and elite athletes who participate in ITU races, perhaps beginning in the 2017 season. This follows on the heels of the international rowing federation adopting a similar policy, gradually, during the 2014 and 2015 seasons.

I worry a little about the ITU focus on elite athletes, since the problem of race-related fatalities seems to be largely one of age-group athletes, but I hope that age-group athletes will be paying attention to any recommendations that are implemented.

Lastly, I’ll close with some photographs from the trip. Since this was my first-ever visit to Tokyo and Japan, my hosts graciously afforded me about 8 hours of free time one day for the purpose of sightseeing and I took advantage. I hope to return to Japan soon to see even more.