Exercise & the heart

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.

A Conversation with Cyclist and Heart Transplant Recipient, Paul Langlois

December 10, 2015 By Larry Creswell, MD 8 Comments

I recently met Paul Langlois–online, at least. Many thanks to Joe Friel for making the kind introduction.

I’ve had a chance to chat with Paul and thought I’d share his interesting story here at the blog. Paul is a long-time recreational and competitive cyclist who developed a rare medical condition called amyloidosis. His heart was particularly affected. He developed life-threatening heart failure and required a heart transplant as the only effective treatment. He has now made a great recovery and has returned to his passion of cycling.

I know that heart transplantation remains a bit of a mystery for most non-medical folks. In part, it’s just a rather uncommon operation. Last year in the United States, for example, 2,655 individuals underwent heart transplant operations. Here at the University of Mississippi, I’m involved in about 10-12 heart transplant operations each year. For the patients who need the transplant operation, the results are usually quite remarkable.

It’s very unusual, though, for lifelong athletes to need a heart transplant operation. And that’s why Paul’s story is so very intriguing. He kindly agreed to answer my questions about his experience….

Thinking back to before your heart transplant, can you tell us a little about your interest in cycling? When did you get started? Were you involved in team cycling? Or competitions, of various sorts?

Yes, I had been actively involved in competitive Masters cycling since the age of 30, attaining Category 2 status on the Road, Track, and Cyclocross. Before I became a cyclist, I competed in collegiate rowing at the Coast Guard Academy, winning three national titles. After college, I got hooked on the running boom and completed four marathons (qualified for Boston), ran many shorter events, and did some medium distance triathlons. Problems with my right knee resulted in two surgeries when I was 30, when I switched my competitive focus entirely to cycling, which was became part of a long rehab process for the knee. Only a few years later at age 34, I won the All-Military National Cycling Championships stage race in Colorado Springs. Over the years, I had competed at over 20 various Masters National Championship events for road, track, and cyclocross. Somewhat surprisingly, some of my best performances on the bike were attained in my early 50s, when I won two consecutive years as Best All Around Rider 50+ in the Mid-Atlantic District, and rode a Personal Best 40K Time Trial in 54 minutes. I raced with numerous amateur teams in different parts of the country, as the Coast Guard typically relocated me to a new duty station every three years. I served for 30 years in the Coast Guard, primarily as a helicopter rescue pilot, and retired as a Captain in 2006. After retirement, and settling in Santa Rosa, California, I continued non-stop racing, until a year before my diagnosis at age 56, mentioned below.

I understand that you were diagnosed with cardiac amyloidosis, a rare cause of heart failure. How did you and your doctors discover this problem?

It took me a bit more than one year of frustration before I was properly diagnosed. I attribute my eventual diagnosis in large part through my own keen awareness of my slow, but steady deterioration in fitness level. Initially, I noticed that I was having trouble keeping up with my teammates on training rides, especially when climbing. And then, soon thereafter, I had to pull out of a criterium race after two laps, experiencing almost no aerobic capacity, in the same race I had nearly won the year prior. I first checked with my primary care physician, who commented “I was simply getting older”, which I refused to believe was the problem. I was later referred to a cardiologist and a pulmonologist for stress tests and neither test came back with any abnormality. Over the next six months, I progressed into becoming short of breath when climbing one flight of stairs, and nearly fainting when I quickly rose out of a chair. I noticed my legs and ankles were swelling in a way which I had never seen. Finally, I checked myself into my local ER, and by a stroke of luck, a talented cardiologist was on duty who performed an Echocardiogram, an EKG, a chest xray, and did some lab work. He noticed I had very high protein in my urine, and suspected I might have Amyloidosis. The following week, I had a heart biopsy, and a special test revealed I was positive for Amyloidosis. This was the cause of my heart failing, and it readily became apparent to me that it was a life and death situation. I was referred to Stanford Hospital for further evaluation, as they have one of the few clinics in the USA with significant experience treating this rare blood disease.

Once heart transplantation was recommended, how long did you spend on the waiting list? And during the waiting period, were you able to exercise? What was your fitness level right before the transplant operation?

My first consultation at Stanford was with their Cardiology Dept, which recommended heart transplant, as no other option was available to keep me alive. I went through the pre-qualifying tests successfully over a period of six weeks, until I was allowed to be listed for transplant. I have Blood Type AB, and was listed as Priority 1B, and I was extremely fortunate to only have to wait for eight days until a good match was found for me. Leading up to the transplant, my fitness level had diminished considerably over the past year due to the onset of heart failure, although I still attempted to get exercise, primarily through cycling. As an example, in the months just before transplant, I was not able to get my heart rate over 130, when giving it my hardest effort, whereas the previous year before I became ill, I could easily exceed 165 during a hard effort.

Tell us a little bit about your early recovery after the transplant operation. How long were you in the hospital? When did you begin walking, afterwards? How long did it take to get healed up?

Heart Transplant is obviously a very traumatic surgery, including the need to separate the center of the rib cage to perform the transplant. And so the body needs many weeks to heal and rest afterward. I spent only one week in the hospital. I was up and walking slowly around the ward within three days. After discharge, I was required to live nearby Stanford for many weeks with a Caregiver (my wife Linda), to allow for frequent clinical check ups at Stanford, including many heart biopsies, Echos, and labwork, with a focus on ensuring no organ rejection might be taking place. I began exercising very gently at first, and then with steadily increasing intensity and distance as the weeks went by. Within one month and much to my surprise, I completed a six mile hilly walk around the Stanford Campus. I had to wear a protective mask whenever I was outside or around people to minimize any chance of catching an infection or virus. I finally got to go home at almost two months after the transplant which was a wonderful day.

I understand that you’re back to cycling now. What’s your routine? Are you still competing?

Yes, I have been able to get back into cycling, but have not been able to develop the required fitness to race competitively. Having said that, I still have the mental mindset to someday be competitive, and so I keep training with the belief that I may attain that level again. Unlike many who have heart transplant, my case is much more complex and challenging, as I still have the underlying blood disease to deal with, which required a stem cell transplant just six months after the heart transplant. As I approach the five year mark, I have endured almost nonstop chemotherapy treatments, and clinical trial drugs. Amyloidosis has no known cause, and still has no proven cure. My kidneys have become involved with Amyloid damage (Stage 3 failure), and I have to battle fatigue with anemia. As a result, my ability to train hard and go for long endurance is diminished compared to my earlier success. But, as an example, I was able to complete two 75 mile charity rides within two years after my transplant, and still routinely cycle 3-4 times per week, typically between 1-3 hours each session. I also spend lots of time in the gym with weight training and physical rehab, as I also elected to have a total right knee replacement two years ago, which set me back for awhile. Despite the pain, side effects from medication, and lesser ability to push myself, I enjoy getting out and riding the bike frequently. In the past few months, I have begun to challenge myself on much steeper and longer climbs, and have started to incorporate various interval sessions and sprint workouts. I am getting back into group riding with my teammates again. I have a goal to try and enter some low key racing next year in my 60+ age group, provided my health remains stable.

As you know, the autonomic nerves (from the “involuntary” nervous system) that supply the heart are cut during the transplant operation. As a result, some of the usual mechanisms that influence the heart rate during exertion aren’t available after heart transplant operation. Have you noticed this? And, if so, how has this situation affected your exercise routine or training?

Yes, without any question, I have noticed significant changes in how my heart beats and reacts to demands. Since denervation takes place after transplant, my new heart has a resting heart beat of about 85, whereas it used to be about 44. In the first year after transplant, I noticed during exercise that it would take me about 20 minutes to get my heart rate to a maximum of 120-125. And then, once I eased off the intensity and started to rest, the heart rate would not drop down very quickly. But as the years have gone by, and I have trained consistently, my new heart responds to effort much quicker, and so I can get my heart to rise up over 120 in less than five minutes, and my maximum heart rate after climbing a long hill is about 155. And when I slow down, the heart rate drops much quicker than the first year, but not nearly as fast as when I was in great shape with my original heart. My resting heart rate has not dropped with time, and it remains just above 80 at its lowest resting rate, which I am told is quite normal for heart transplant patients. When I ride, I try to warm up gradually for the first 15 minutes, before applying much intensity, and I have found that I tend to really feel much better after about one hour on the bike. But, I also can report that I do not recover nearly as fast as I used to after a long workout, and so I typically do not ride on consecutive days, to ensure I get sufficient rest and recovery.

Recipients of organ transplants must take anti-rejection medications, usually forever. These medications sometimes hinder the body from dealing effectively with infection. Has this issue affected your cycling? Do you have strategies to prevent illness?

Yes, I definitely have concerns about having to take two different immuno-suppressant medications every day, supposedly for the rest of my life. On one hand, they serve to prevent organ rejection, but on the flip side, my body is much more prone to catching virus and various illnesses. As an example, I had a very difficult year last year (2015), when after the total knee replacement, I came down with shingles all over my body, which took over a month to clear, including hospitalization for a week. Following that episode, I came down with pneumonia, which had me inpatient in isolation for two weeks, and didn’t clear until two months later. If that wasn’t bad enough, this past April, my spleen ruptured due to Amyloid involvement, requiring an emergency splenectomy. While not all of these may be attributable to the anti-rejection drugs, I believe these medications make my body very fragile and less able to fight infections and germs. As a result, I try to be very careful to minimize exposure, especially in public places around large gatherings. I constantly wash my hands and avoid people who appear to be sick. My predicament sometimes means I have to avoid certain social situations in order to lessen my exposure. I wear a protective mask whenever going into hospitals or clinics. I have learned that winter time is a very high risk time for me, so I ensure extra precautions, especially during the Holidays.

Related Posts:

1. Another Heart Transplant Triathlete

2. Ironheart Racing Team

Laurent Vidal, Elite Triathlete 1984-2015

November 15, 2015 By Larry Creswell, MD Leave a Comment

The very sad news came this week that retired French elite triathlete, Laurent Vidal, died in his sleep at his home in southern France.

There has been a worldwide outpouring of emotion. I particularly enjoyed this video.

Life-threatening heart problems are unusual in Olympic-caliber athletes, but Vidal suffered an episode of cardiac arrest at the swimming pool last spring. I wrote about that episode and his remarkable recovery in a blog post that focused on cardiac arrest, more generally.

After his recovery, Vidal shared very little about his diagnostic evaluation, any conditions that were discovered, and any implications regarding his prognosis. He immediately retired from the sport of triathlon, though, and I suspect that he was advised that continued participation posed some danger. He remained physically active over these past months, though, and often shared pictures of himself bicycling or hiking. Media reports this week mention a pacemaker and I wonder if he actually received an internal cardioverter-defibrillator (ICD) for “secondary prevention” in case of a repeat episode of cardiac arrest. Unfortunately, even an ICD doesn’t guarantee long-term survival in situations like this. It’s worth reflecting that Vidal’s first indication of a potential problem was a couple years earlier, when he had an episode of syncope, or fainting. That’s an important problem to get sorted out.

Vidal’s story surely reminds us that life is sometimes too short. The remembrances on social media this week speak to the way that Vidal embraced life. I wish I’d had the chance to meet Vidal. I’ll always remember his smiling face.

Related Posts:

Thoughts on the Recent VeloNews Article

September 1, 2015 By Larry Creswell, MD 3 Comments

I enjoyed reading a recent article in VeloNews by Chris Case, entitled “Cycling to Extremes: Are endurance athletes hurting their hearts by repeatedly pushing beyond what is normal?” The article is good reading.

First, I give a lot of credit to Chris Case and the editors at VeloNews. It’s great that a publication with such a broad audience would devote time and space to the issue of heart health and endurance sport. In recent months, they’ve also brought attention to the heart problems of pro cyclists, Robert Gesink, Olivier Kaisen, and Eddy Merckx. I wish that other writers and publications would do the same.

I also thank Lennard Zinn and Mike Endicott for sharing their personal stories with their heart problems. It would be very easy to keep quiet. I very much enjoy reading personal accounts such as these. Their stories are real and also familiar. This is how we learn.

Since the article was published, I’ve gotten a bunch of inquiries asking my opinion about the article in general or about specific information that was presented. Let me share a few thoughts that may be helpful to readers here at the blog….

Don’t be scared (too much)! For most people, cycling is a healthy pursuit. In general, exercise is healthy and provides a myriad of benefits. So don’t stop cycling! It’s important to keep in mind that the stories of Zinn and Endicott are not the norm, even among veteran endurance athletes. Zinn’s multifocal atrial tachycardia (MAT) is one of the least common atrial arrhythmias and Endicott’s sudden cardiac death is rare. As you absorb their stories, focus not on the particular arrhythmias but rather on the possibility that an arrhythmia–any arrhythmia–can cause significant problems or be an indication that things are amiss with the heart. In that sense, their stories should cause you to put on your thinking cap.

My favorite quote from the article? “But fit for racing doesn’t necessarily equal healthy.” Readers here at the blog will know that I’ve said this repeatedly. It’s easy for seemingly healthy endurance athletes, particularly men, to believe that fitness is the same thing as healthiness. This isn’t necessarily true. To dispel the myth, I’ve shared the stories of many elite endurance athletes who’ve struggled with heart problems of various sorts. We can add Zinn and Endicott to these lists. Heart problems are common….and athletes aren’t exempt. This is the most important take-home message from the article.

Arrhythmias are common–in athletes and non-athletes, alike. All athletes experience arrhythmias. Infrequent premature beats, originating in either the atrium (premature atrial contractions, or PAC’s) or in the ventricles (premature ventricular contractions, or PVC’s) most likely have no consequence. Sustained arrhythmias, on the other hand, deserve attention and evaluation. There are far too many varieties of arrhythmias to consider here, other than to mention some of their names: SVT, or supraventricular tachycardia; WPW, or Wolff-Parkinson-White syndrome; atrioventricular (AV) nodal re-entry tachycardia; atrial or ventricular bigeminy; sick sinus syndrome; sinus bradycardia; atrial fibrillation (AF); atrial tachycardia; MAT; ventricular tachycardia (VT); and ventricular fibrillation (VF).

The last part of the VeloNews article alludes to AF. Other than sinus bradycardia (simply a heart rate slower than 60 beats per minute, which may be very healthy in athletes) or innocuous premature beats, AF is probably the most common arrhythmia in athletes. We know from longitudinal studies that the lifetime risk of having AF is approximately 25% in the general population. The question of whether athletes–and endurance athletes, specifically–are more prone to AF is a current controversy, with important implications for long-term endurance athletes. I’ll try to finish up a separate blog post that summarizes the accumulated evidence on this issue. For men, there may be an association with long-term exercise and the prevalence of AF, but there is certainly no consensus among experts. For women, the evidence does not suggest an association between long-term exercise and AF.

Pay attention to warning signs. I particularly like the last section of the article, written by Dr. John Mandrola. He’s a cardiologist who specializes in arrhythmias and who is also a (former?) triathlete and current avid cyclist. He provides good advice in the Q&A. I like to talk about 5 important warning signs of possible heart disease: chest pain or discomfort, especially during exercise; unexplained shortness of breath; light-headedness or blacking out (syncope), especially during exercise; unexplained fatigue; and palpitations–the sense of a rapid or irregular heartbeat. Any of these warning signs may be due to an arrhythmia. All deserve investigation. Dr. John makes the apt point that, very often, heart rhythm problems start off small and get worse with time. Not surprisingly, it’s best to get things sorted out earlier rather than later.

Less may be more. Lastly, I would encourage athletes with identified arrhythmias to be open to the idea that less exercise may be helpful. In fact, this may be the most appropriate prescription. For the long-term endurance athlete, this can be difficult to accept. In this regard, the stories of Zinn and Endicott are particularly poignant.

2. Atrial Fibrillation in Athletes (in a Nutshell)

3. Too Much Exercise, Revisited

4. Don’t Stop Running Yet!