The cardiovascular system
The most common problem relating to the cardiovascular system is coronary artery disease–and many patients die within the first few hours of a myocardial infarction (MI), or of heart failure after several years of ill health. All cardiac muscle has the intrinsic capacity for rhythmic excitation. Ventricular muscle fibres can contract on their own at a slow rhythm, but are usually excited through the specialised conducting tissues. Patients with ischaemic heart disease may also have symptoms of vascular disease in other parts of the body. The most common of these is intermittent claudication, a cramp-like pain in the legs on walking, which is relieved by rest. A family history of heart disease is a significant coronary risk factor. It is important to establish the age of the relative when these events occurred, as MI runs in families.