<P> Diseases affecting the cardiovascular system are called cardiovascular disease . </P> <P> Many of these diseases are called "lifestyle diseases" because they develop over time and are related to a person's exercise habits, diet, whether they smoke, and other lifestyle choices a person makes . Atherosclerosis is the precursor to many of these diseases . It is where small atheromatous plaques build up in the walls of medium and large arteries . This may eventually grow or rupture to occlude the arteries . It is also a risk factor for acute coronary syndromes, which are diseases which are characterised by a sudden deficit of oxygenated blood to the heart tissue . Atherosclerosis is also associated with problems such as aneurysm formation or splitting ("dissection") of arteries . </P> <P> Another major cardiovascular disease involves the creation of a clot, called a "thrombus". These can originate in veins or arteries . Deep venous thrombosis, which mostly occurs in the legs, is one cause of clots in the veins of the legs, particularly when a person has been stationary for a long time . These clots may embolise, meaning travel to another location in the body . The results of this may include pulmonary embolus, transient ischaemic attacks, or stroke . </P> <P> Cardiovascular diseases may also be congenital in nature, such as heart defects or persistent fetal circulation, where the circulatory changes that are supposed to happen after birth do not . Not all congenital changes to the circulatory system are associated with diseases, a large number are anatomical variations . </P>

Is the stomach part of the circulatory system