Your SVG are not strong vessels, Veins just aren't up to the same punishment as arteries and this is well known. You did seem to get 10 years out of them, which isn't bad. The Lima will last a very long time. With the new tools etc for angioplasty which have appeared in the last 10 years, I would find a more confident/experienced cardiologist. Ask your existing one to recommend someone, they know who the best are. They should be able to get your native vessels opened, your OM1 and Diagonal 1. It's all about the experience of the cardiologist and finding them.
Hello and hope you are doing well.
Understand your predicament, but it difficult to suggest further course of therapy as this will depend on the extent of damage to the cardiac muscle and your symptoms. With your present symptoms of chest pain and breathlessness, its likely that the cardiac function is inadequate. What is your ejection fraction? The ejection fraction is a useful measure of left ventricular performance. The normal range is 63-77% for males and 55-75% for females. It reflects the pumping capacity of the heart.
Please discuss in detail all the treatment options with your doctor, it will help you decide. And Good Luck with your therapy.
Hope this helped and do keep us posted.