My son (early 40's) suffers from a low heart rate and after passing out twice when under hard exertition and was fitted with a pacemaker to keep his heart rate up but does not have any blockage . Has had it over 5 years and has had good results. Get a qualified second opinion from a cardilogist with an exercise background. Most cardilogist are used to treating "couch potatoes" so you may have to travel to get to the right one.