Abstract: In a first aspect, the current invention concerns a computer-implemented method, system and computer program product for identifying a zone in a blood vessel system with a risk level for stasis, comprising the following steps: a) providing an angiogram of a blood vessel system, said angiogram comprising a time series of images of said blood vessel system, at least some of said images showing a contrast agent present in said blood vessel system; b) identifying at least one zone within said blood vessel system on a multitude of images of said time series; c) characterising variations in grey-scale intensity in said zone across at least part of said time series of images; d) characterising an outflow of said contrast agent from said zone on the basis of said variations in intensity in said zone; and e) providing a local risk level for stasis in said zone.