Hello Welcome to HCM Ischemic colitis is caused due to obstruction to blood flow of the colon. Cholesterol deposition in the arteries of the body lead to narrowing of the arteries. This is called atherosclerosis. Some subjects have increased tendency to atherosclerosis which depends on genetics and environmental factors. This causes narrowing of the arteries leading to stagnation of blood at these sites and subsequent formation of clots. This causes you the attacks of ischemic colitis. In you case since you have suffered from two heart attacks, I suppose you have got high propensity to atherosclerosis, may be due to genetic factors and strong family history. Treatment is blood thinners like aspirin which I suppose you are already on. Usually two blood thinners are used on recurrent attacks of ischemic colitis and even in case of previous heart attacks. So ideally you must be on two blood thinners. If despite this you have episodes of ischemic colitis you must be on higher blood thinners like warfarin. However higher blood thinners have a potential of causing of causing bleeding elsewhere in the body. I hope I have answered your query satisfactorily. Wishing you good health Regards.