I Have Been Going To Doctor's For 3 Years Now

i have been going to Doctor's for 3 years now and I still do not have an answer for my problem. Sometimes when I get physically active it gets relly hard to breathe. Mostly when I am bending over,crawling like at work sometimes or with my wife. I used to get blood in my lungs but, when they were looking for the cause of this problem they found i needed open heart surgery. I had this done April 29th,this year. After I got over this we thought my problem was gone but, as I got stronger and more active the breathing problem has come back. When it happens I usually end up in the hospital. Sometimes they keep me and put me on oxygen till this gets back to normal. I always get real sore at my soft spot on my chest and sometimes it last 3 or 4 hours and sometimes all night. So far i'm not coughing up blood like I used to but I recently spent 3 days in the hospital again. I will gve you info on what tests that I have had done so far and I really would appreciate your help if possible. 6 CT scans,1 of which shoed blood in my lungs in January of this year. Its kinda like a bad cold wher you spit up junk for awhile then it goes away overnight. I've had a scope in my lungs twice,scope in my stomach twice,tube in my sinuses, heart echoes 3 or 4, EKG 2 or 3,Ultrasound 2 times,colonoscopy, dozens of x-rays,dozens of blood tests. I have been to a dozen doctors that don't have a clue what causes this. I have to get it fixed if possible cause one day it might put me down for real. I also currently have a lung doctor and a heart doctor that I see every 3 months or so. Any ideas would be appreciated. Symptoms, coughing up blood,shortness of breath,low oxygen levels,sometimes nausea,sometimes dizziness,pain in soft spot area of my chest,wheezing,sometimes hard to walk. Thanks