A heart attack is the death of heart muscle caused by blockage of a coronary artery. Medically referred to as a myocardial infarction, this condition occurs when a coronary artery is blocked, depriving the heart of blood and oxygen. This deprivation to the heart causes chest pain and pressure, injury to the heart, and possibly death.
Though a heart attack occurs suddenly, the cause can be sudden or gradual. The leading cause of heart attacks is artherosclerosis, or hardening of the arteries, due to the build up of plaque caused by cholesterol deposits. If artherosclerosis occurs in the coronary arteries, the gradual narrowing of these arteries begins to have an impact on the heart muscle and eventually leads to an infarction. Similarly, a blood clot can also create a blockage of a coronary artery ending in the same result.
The symptoms of a heart attack include chest pain and pressure, shortness of breath, arm and upper back pain along with possible nausea or vomiting. However, medical experts have estimated that close to 25 percent of attacks are silent, giving the patient no warning symptoms whatsoever. This is why routine health care, including monitoring risk factors and heart heath, is important.
Whether a heart attack carries severe symptoms or none at all, the damage can be the same. A heart attack is considered a life-threatening emergency and any signs or symptoms, no matter how mild, should be checked by a doctor. Delaying treatment increases the chance of permanent damage and reduced heart function or even death. The longer the heart is deprived of adequate blood flow and oxygen, the more damage done. If a large enough amount of heart muscle dies, heart failure will follow.
Further, injury to the heart muscle can also lead to ventricular fibrillation, which is an irregular heart beat caused by abnormal electrical activity. If the heart fails to beat and pump blood normally, blood supply to other parts of the body, including the brain, is disrupted. Brain damage can occur within a matter of minutes if it is deprived of the oxygen it needs.