Weakness/Chest Discomfort after exercise
I am 39. Over the last few years, I have had several episodes after exercise (typically following extreme exertion while hiking, squash, skiing, spinning) where I felt very weak afterwords for a period of hours or even days. The aftereffects were sometimes associated with the inability to exert myself without "feeling bad" and having pressure in my chest area or upper/middle abdomen.
If I rest the symptoms go away but it may take hours or days. On a couple of these episodes I have also had accompanying symptoms that some doctors have described as vasovagal symptoms.
In the last few years, I have visited the ER twice, my GP twice, and two different cardiologists. I have had a nuclear stress test, chest CT, basic echocardiogram, EKGs, many rounds of blood work, all showing nothing sinister. My general health and weight are normal. My BP and cholesterol have always been very, very good. No murmurs. I sleep well and 7-8 hrs per night. None of my doctors could find anything wrong with me and seemed puzzled.
I generally stay fit and exercise. I was a college football player and after college ran for exercise consistently, and generally stayed very active, hiking, skiing, running triathlons, playing sports, etc. However, about four years ago, I started a new stressful job that required me to sit at my desk for 12+ hours a day. Also, my exercise habits have been more intermitted since then, in part because I quit running due to hip problems (acetabular cam impingement). In the last 5 years I mainly have been using the elliptical machine, swimming, and/or weight lifting, due to the hip problems. Also, my workouts have been at lower intensities due to anxiety about these episodes and more intermittent due to my new job.
Another piece of information that may or may not be relevant, is that 7 years ago I had an episode of hyponatremia following a 6 hour half ironman triathlon in Florida. I felt weak and dizzy after the 6 hour race in +80F heat and the medical tent gave me two units of IV fluids which made my dizziness much, much worse. After a couple of hours I asked to go to the ER. The ER doctor resolved the problem pretty quickly with salt tablets. But he kept me in the hospital for 2 days due to exertional rabdomyalysis. He said my CK levels were rising and until they stopped rising they wouldn't let me out or I had a risk of kidney damage. He also mentioned that extreme races like that could damage your heart. Though he later told me my troponin levels were normal. Since then I have read online that extreme exercise very rarely leads to heart damage.
When I showed my GP the medical records from my hospital stay he said he thought the hospital overreacted by admitting me because "of course my CK levels would be rising after an extreme event like a triathlon", and likely the hospital was trying to protect themselves by admitting me.
I don't know what to do. I do not want to continue getting expensive tests, especially when doctors don't seem to have any good hypotheses about what might be wrong.
During my last cardiology visit a month ago, my very experienced NYC cardiologist said I was an enigma and implied it was anxiety related (as have other docs). He asked me what I wanted to do and when I mentioned that I hadn't had a stress echo he referred me for one. Also, he mentioned an angiogram and potentially trying to rule out diagnoses by experimenting with a beta-blocker and/or CCB. I didn't like his plan.
My latest theory is that I have these episodes when I exercise at or near my max heart rate for extended periods. So I am going to start wearing a heart monitor when I exercise and experiment with exercising at different heart rates. How I developed this theory: After having felt fine after consistent, moderate exercise in the last month, I stepped up my 30 min elliptical workout to near my max heart rate (the HR monitor on the machine read 200 at one point). The next day I felt mild symptoms as described above. After a couple of days of rest I was able to resume my moderate work outs without feeling bad.
Any ideas of what might be causing this? I don't want to avoid hiking, skiing and sports where I heavily exert myself. But I am scared to resume these activities until I feel I understand this better.
I suspect it is not atherosclerosis given my age, negative stress test, and otherwise good health and diet. I do have a family history or heart disease, but my health habits have been significantly better than those aflicted family members.
I don't think it's a valve problem since I do not have a murmur and have a negative basic echo. I haven't done a stress echo though.
I doubt it's arrhythmia related, since my EKGs during the stress test and during ER visits while experiencing symptoms were normal. Though I haven't done a holter monitor test.
Again, any ideas?
Could I just be more out of shape than I think due to my lower level of exercise in the last few years and thus over-exerting myself?
That said, I have friends who are approaching middle age, are more out of shape than me, and do weekend warrior stuff without having these symptoms.
Could I have damaged my heart during the half ironman triathlon? Wouldn't my troponin tests have indicated this?
Any suggestions would be appreciated.