For patients, the act of getting the scan is no different, but the results are sent off to Oxford, analysed by Caristo, and returned within a handful of days. The difference between a regulation coronary CT scan and the new analysis lies in what comes after the scan itself, when the images are inputted into CaRi-Heart. Scientists say that although plaque build up is a serious problem, around half of all heart attacks do not occur in fully-blocked arteries. The other half are caused when small pieces of plaque rupture, releasing cholesterol into the blood which triggers a clot and ultimately leads to a heart attack. These are impossible to predict with current CT scans.