What is myocarditis, and how is it different from a heart attack? As a runner, do I need to worry about it? These are a few questions that went through my head recently after what happened to John Parker. He was reported to have had a heart attack, but that was not actually the case. In a recent update on his caring bridge site (see journal entry dated 10/13/2007 04:39 PM CDT), John wrote the following:

One thing I wanted to make clear about what actually happened to me. I did not have a heart attack, as the term is normally understood. Under catheritization, the doctors found no blockage of my coronary arteries, other than a single blood clot (probably the result of my recent atrial fibrillation), and even that wasn’t stopping the flow of blood.

What I had, as Jerry has written previously, was an attack on my heart, by a virus. It can be caused by a bacterial infection as well. These are systemic, very dangerous attacks that can happen to ANYONE, runner or not, at any age.
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So PLEASE, all you runners out there, be aware (as I was not) of this “other kind” of heart attack (myocardial carditis) are not in the least immune to it, and I would argue that we are perhaps MORE susceptible to it because of our propensity to just bull our way through all sorts of aches and pains.

When you are have a serious infection or are sick, tough workouts and races can help speed the bacteria or virus through your body and make it easier for it to reach your heart. John gives some examples of a friend of his who scraped his knee and got a staff infection the day before a marathon, and ran despite not feeling well. He died in the hospital the next day.

My general inclination when I begin to get sick is to back off for at least a few days in order to give my body a chance to recover when I am sick. I do not plan to change my general practices on that, but this certainly does not make me think that I am wrong to do so. Most of the time, I probably would have nothing to worry about, but it is certainly worth bearing in mind that this can happen to anybody no matter what kind of shape that you are in.

More information can be read about myocarditis from the American Heart Association.