American Medical Association Family Medical Guide - American Medical Association [325]
In some cases after a heart attack, a blood clot may form inside one of the four chambers of the heart. If the clot breaks loose, it can travel through the bloodstream and cause damage to tissues elsewhere in the body. For example, if the clot blocks an artery that supplies blood to the brain, the result is a stroke (see page 669). Sometimes damage caused by a heart attack weakens and stretches one of the walls of the heart chambers, causing a bulge in the wall called an aneurysm (see page 599). An aneurysm can grow and burst without warning, causing uncontrolled bleeding (hemorrhage). Inactivity during bed rest may cause blood clots to form in the veins of the legs (deep vein thrombosis; see page 605). These clots can break off, travel through the bloodstream, and block an artery that supplies blood to the lungs (pulmonary embolism; see page 606).
Heart attack
A blood clot is more likely to block an artery if the artery walls have been narrowed by a buildup of plaque. A blood clot in a coronary artery—a condition called coronary thrombosis—can block blood flow to the heart muscle and cause a heart attack. The area of the heart muscle normally supplied by the artery becomes damaged.
Risk Factors
The following risk factors increase your chances of having a heart attack. While some of these can’t be changed—such as family health history, race, and gender—others can be modified or eliminated through lifestyle changes.
• Family health history If siblings, parents, or grandparents had heart attacks at an early age, you are also at risk.
• Gender Men are at greater risk of having a heart attack than women before age 55. After menopause, a woman’s risk is the same as a man’s.
• Undesirable cholesterol profile An unhealthy cholesterol profile (see page 146) promotes atherosclerosis, which increases your risk of having a heart attack.
• High blood pressure Uncontrolled high blood pressure promotes atherosclerosis (see page 557).
• Smoking Smoking (including exposure to secondhand smoke) raises blood pressure, damages artery walls, and increases the risk of blood clot formation.
• Diabetes Uncontrolled diabetes promotes atherosclerosis and increases blood levels of LDL (harmful) cholesterol.
• Race Blacks are at greater risk of having a heart attack than people of other races.
• Lack of exercise A sedentary lifestyle often results in weight gain and a poor cholesterol profile.
• Being overweight Weighing more than your ideal body weight (see page 51) increases your risk for high cholesterol, high blood pressure, and diabetes.
• Alcohol consumption Drinking excessive amounts of alcohol can lead to high blood pressure and can raise blood levels of triglycerides (a potentially harmful type of fat in the blood).
• Stress In some people, long-term stress can contribute to high blood pressure.
Symptoms
Symptoms of a heart attack vary in type and intensity from one person to another and from one heart attack to another in the same person. Some people may have a heart attack and have no symptoms. However, in most cases, the main symptom of a heart attack is sudden pain in the center of the chest. Some people describe the pain as a feeling of tightness, pressure, or fullness, or a squeezing sensation. The pain is usually severe and may spread to the back, left arm, neck, jaw, upper abdomen, and sometimes to the right arm. The pain may be continuous or may last for a few minutes, fade, and then return.
Location of heart attack pain
Most people who have a heart attack have recurring chest pain, shortness of breath, and fatigue for a few days before the attack. In some people, arrhythmia (irregular heartbeat) may also precede a heart attack. Unlike angina, the pain of a heart attack is not relieved with rest or after taking nitroglycerin