From my point of view, I would appoint a cardiologist to monitor what is going on and its progression. As you change your lifestyle, eat better and exercise you heart will be happy! I would get a second CT-Scan in 2 years to see the progress (hopefully it will go down).

Also I suggest reading about insulin resistance and its effect on the arteries.

I also had a high score. It's scary but I am taking this as a lucky warning for reducing my risk of stroke or heart attack.