Using the calcium score alone:
A calcium score 400-1000
In this study a 400-1000 score was associated with a 4.8% 1 year risk of a heart event (1). So your estimated 10 year risk would be 48%.
Any 10 year risk 20% or higher is considered high risk. According to this study, your risk is significantly high.
Write that number down: 48%.
Because most events happen in the highest percentile groups, we will use your percentile score next.
This study followed 632 patients for 32 months (+/- 7 months) for heart attack or sudden cardiac death. Most events occurred in the highest percentile groups (those with more calcium than others their age). Raggi, et.al. Identification of Patients at Increased Risk of First Unheralded Acute Myocardial Infarction by Electron-Beam Computed Tomography. Circulation. 2000; 101: 850-855