I am 54 and very athletic. I had one stent put in 7 years ago and 2 more a month ago even though on medicine and a better diet (high cholesterol). During last procedure they had to block (jailed) the first diagonal. Operating Doctor tried but could not avoid (said would be no issue). After nuclear stress test my cardiologist says it showed modeler sized area of ischemia in the mid anterolateral wall, apical lateral wall and to some degree the mid anterior wall. There was evidence of infraction involving the basil to mid and apical interior wall and apex. This was due to jailed diagonal. My exercise tolerance test was exceptional. I know I am lucky and accepting that I have heart disease but the doctor is recommending that I keep my heart rate below 80% which limits my bike riding. Question: does this blocked diagonal impact flow that much to warrant 80%, why not 90% limit?