hi i am a doctor you know you should have stated what disease you meant heart disease is a vast group of disease i asume you are talking about heart attack, or angina in this case i advise you take a break of at least three months it seems that the sex activity are equal o moderate exercise if your stress test get within normal limit or if you can do routine activity normally or after three months ( whichever is later) you may start with the activity in emergency :) you may try the antianginal drug your doctor prescribes if it is a vasodilator but i would strongly recomend the non treatment tecnique