Continuing improvements in medical technology have dramatically shortened the period of recovery from surgery and illness. Advances in surgical procedures and techniques have made many types of surgery less damaging to the body. New discoveries in drugs have made life-threatening diseases relatively controllable. As a result, hospital stays have become considerably shorter. For example, when a person had a heart attack 40 years ago, he or she had to stay in bed, in a hospital, for six weeks. More recently the hospital stay was still six weeks, but the patient was allowed out of bed at the end of three weeks. Studies now show that heart attack patients who have no setbacks in the first four days in the hospital can be safely discharged and sent home in less than two weeks, sometimes even in one week. Follow-ups have shown no serious complications or deaths six months after discharge.