When the circulation of blood through the coronary arteries—the arteries that feed blood to the heart muscle—decreases too much, a portion of the heart muscle dies. This is a myocardial infarction, or a heart attack. Hardening of the coronary arteries occurs because of the deposition of cholesterol in the walls of the blood vessels. These deposits prevent the blood vessel from relaxing and opening wider when necessary, and they also may narrow the existing opening in the blood vessel, impairing the flow of blood. The surface of these narrowed cholesterol-filled areas may become covered by a blood clot that stops the blood flow. Any of these changes may produce a myocardial infarction.
A heart attack is a life-threatening illness. If the amount of heart muscle that dies is large, the heart will be unable to pump enough blood to sustain the body’s needs, and death occurs. Even if the amount of muscle lost is small enough to permit the heart to continue to serve as an adequate pump, there is the danger that the weakened heart wall may rupture or the danger of damage to the heart’s conduction system, either of which also may result in death. Blood clots may form on the damaged heart wall, and, if they break free, the clots can enter the circulation and cause damage where they finally lodge. The heart may be so crippled as a pump that there is limitation of other physical activity.
The common sign of a heart attack is chest pain. This is most often felt in the front of the left side of the chest. Additional pain may be felt in the neck, jaw, left shoulder or left arm, or back. Less commonly pain may be felt in the abdomen. The pain may mimic gallbladder disease, ulcers, or heartburn. As the severity of the heart damage increases, other symptoms and signs may appear. If there is beginning heart failure, breathlessness will be prominent. The heart may race unusually fast or become abnormally slow. With heart failure there is weakness, and swelling of the lower legs may develop.
Important Points in Treatment
A myocardial infarction is always an indication for hospitalization. Where such facilities are available, patients are placed in specialized areas called coronary care units. This allows the patient to have continuous monitoring of the heart rate and rhythm. The trained nursing personnel in coronary care units have the resources to do cardiac resuscitation.
Rehabilitation after a heart attack is important to support the patient in regaining the maximal level of activity. Other measures can be taken to lessen the likelihood of a second heart attack. Exercise, reduction of the blood cholesterol and other fats, and stopping smoking are important parts of this rehabilitation.
Notify Our Office If ...
- You have sudden onset of chest pain. This is a medical emergency. A heart attack is a life-threatening illness. If the amount of heart muscle that dies is large, the heart will fail to pump enough blood to sustain the body’s needs, and death occurs.