Background: Inflammatory bowel disease [IBD] includes a number of chronic relapsing diseases. In IBD intestinal microvascular endothelial cells are damaged by an abnormal immune response. Several studies have shown that IBD may cause increment in risk of developing atherosclerosis. IBD in activation was related to enhanced risks of worse cardiovascular [CV] outcome, on the other hand no risk increment was seen in remission comparing to control group in those studies. Coronary FlowReserve [CFR] reflects coronary microvascular circulation. Coronary microvascular dysfunction may be defined as a predictor of CV outcome combined with previous described atherosclerotic risk factors. The present study was purposed to further evaluate whether or not CFR in the left anterior descending artery [LAD] is disturbed in IBD patients with activation in comparison to remission and healthy subjects.