What did your Cardiologist say? This forum has no doctors.
You may be managing with a 67 per cent occlusion, but this situation is likely to worsen. My had two abortive heart attacks which involved a greater occlusion. He went to IV chelation and it was almost 15 years before his coronary arteries started to clog again. He did not get chelation in time and had a mild heart attack. Then he went for chelation.