I have been taking Isosorb for 08 weeks the first two days were ok just a couple of flare ups with angina shortness of breath restricted breathing was forced to sit and relax for about 30 min each time. how ever over the next week or so the flare ups had increase. after just a couple of hours from taking the Isosorb with just minimal exertion I start having extreme difficulty breathing with chest and right arm pain. this continued until the 6th week and I stopped taking the Isosorb and began to take 340Mg aspirin. I have had almost no problem since. and when I do have a problem, I take another aspirin and after 20 minutes the symptoms go away. now I have six stents 2 meds and 4 none meds. I 'm not so sure that Isosorb is exactly what I need or am just not compatible with it. maybe the dose is to small I just don't know. I also take 40 Mg provastatin I have severe pain on the bottom of my left heel may not be related to either but didn't have the problem with the heel prior to either Med. next appointment in 4 weeks will discuss with doctor and re evaluate blood work. thinkin about trying " functional red yeast rice" for LDL control.