Infarction: Death of tissue resulting from a failure of blood supply, commonly due to obstruction of a blood vessel by a blood clot or narrowing of the blood-vessel channel.Hypertension is caused by increases in cardiac output, total peripheral resistance, or both.Myocardial infarction (heart attack)--death of a section of heart muscle-- results from obstruction of a coronary artery; the condition often accompanies coronary thrombosis.The veins are usually located on the backs of the calves or on the inside of the legs, from the groin to the ankle.Hypertension is defined as a sustained elevation of systemic arterial blood pressure.Aneurysms usually enlarge over time.