High heart rate and long term damage

Have there been any studies of side effects from consistently spending time at high heart rates. I hit a new observed MHR this weekend at 209bpm, the highest i ever saw was 206.... I did a crit race and i don't think my hr went below 90% for a good 30 minutes or so. My resting pulse is around 43bpm. Makes one wonder thats quite a range for the heart to be dealing with.

Can irregular rythms develop over the long term?
Heart muscle damage?

I've heard that super-athletes ie Olympians are at a significant risk of developing heart problems when they're older as a result of their athleticism. Unless they keep up with the exercise throughout their life, (parts of) their abnormally large heart will begin to turn into fat=bad.

Although that is an interesting theory, there isn't much evidence to back it up.

Some recent research on Ironmen triathletes was done looking at their hearts immediately after a race. Some of them, especially after a worse than hoped for performance, had quite startlingly bad heart functions on echocardiography and elevated blood levels of heart-related chemicals suggesting some damage (temporary?) had been done. Perhaps these extreme levels of endurance exercise can lead to minor degrees of repeated damage which can lead to scarring which can lead to a focus for an abnormal cardiac rhythm.

On the other hand, quite a few pro cyclists have used various performance enhancing drugs and it is unknown what cardiac damage some of these can cause.

I would think that it is unlikely from doing crit races of 30 - 60 minutes.
There is a condition called tachycardia-induced cardiomyopathy. This means heart muscle damage caused by having an elevated heart rate but again this requires quite a bit of time with an elevated HR for the damage to occur.

FYI- Heart muscle cannot turn into fat. Its that the muscle becomes so large it essentially cannot "keep up" with itself, in turn making it larger, and further losing its ability to "keep up" and so on, causing excess stress on the muscle.

Muscle cells are never lost or gained, but only lose or gain in size.

Jacycle, +/- 3 is nothing too serious and additionally HR monitors are never exactly right all the time.

I think the best comment i can make is that if you have a concern, see a doctor and ask for a checkup. However, your resting heart rate is low and its possible you were pushing yourself harder maybe?

Any other symptoms?