I would suggest doing what I do. I have an exercise physiologist as a coach and he monitors FF data from every WO session for ecg irregularities. He has been giving me power based WOs. I,m a cyclist also. Good luck

From all the research I’ve been doing it seems like just don’t sustain a heart rate of that high. So if you set the device to right before that limit, instead of riding through like normal (I tend to overexert myself to just finish) It would make sense to break from normal and do a bit of meditation, lower your heart rate, drink a bit of water. Then get back on the bike and continue. That way you can still enjoy the same level of rides without worry. Though I’m not expert just a dedicated enthusiast with heart health.

I’m the same age, but most of my activity is running. I constrain my training HR – for example when HR = 125 I reduce my pace or walk until it drops to 115, then re-commence. Later in the training cyle constrain at HR 135. This type of training I believe works on the ATP cycle which supports increase in stamina and endurance (below the lactate threshold) – so it sounds like it is fruitful for me without worrying about the heart. When I do a race or public event I let the rate rise unconstrained – like you to around 155/160. Although for longer races I know this is not sustainable – so I have the HR displayed on my watch and ease off a bit during the early stages.I personally would be a bit carelful about too much activity at max HR, recovery symptoms can be a bit dramatic – for example a massive drop in BP – and I don’t want to die!

I would listen to your cardiologist. Also, you may want to get your max heart rate tested. Those calculations are just averages and may not accurately reflect your true max heart rate.