The next step will probably be a catheterisation (angiogram) where the cardiologist will investigate if there are blockages in your coronary arteries that explain your symptoms, where they are and if they can be opened with one or more stents.
Reinstallment is not done, old stents will not be removed. If a blockage appears to be situated inside an earlier placed stent, they can try to place a new stent inside the old one.