AIMING TO MAKE THINGS BETTER

I am a 60 yearold man, i have had astent put in my heart artery, where it was diagnosed 99% blockage. I have been on anti depression drugs, als o taking pills for my heart. I am desperately trying to have a better sexual relationship with my wife, but when I try I cannot maintain an erection, and when i  do have an erection which is seldom I cannot penetrate it well, and soon goes limp. I am sorry but this is the reality of this oldman when it come to having sex. I would appreciate any comments, suggestions, or cures. please help. james