Angina pectoris, or angina pectoris, is a transient pain or discomfort located in the anterior region of the chest, perceived as a sensation of pressure, tightness or burning. Angina pectoris occurs when the heart muscle (myocardium) does not receive enough blood and oxygen. This process is called myocardial ischemia or coronary ischemia, since it is related to the coronary arteries. This deficient oxygenation can be the result of an increase in your needs, by a decrease in supply or even by both mechanisms. The oxygen requirements of the heart are determined by the degree of effort of its functioning, that is, by the frequency and intensity of the heartbeat.
Angina pectoris may be called stable, unstable or variant. It is stable when it always has the same characteristics, that is, the triggering factor, intensity and duration are always the same. In unstable angina pectoris, the discomfort has a greater frequency, intensity or duration, often appearing at rest. This can be a medical emergency, as it can develop into a myocardial infarction or even death. Variant angina pectoris, also called Prinzmetal angina, results from a spasm of the coronary artery. It is so called – variant – because it is characterized by the occurrence of pain with the individual at rest (usually at night) and not during exertion and also, for presenting certain typical electrocardiographic changes.
The main cause of angina pectoris is coronary artery disease. That is, the presence of fatty plaques (atheromas) on the wall of the arteries of the heart. Angina pectoris may be due to other causes, including hypertensive heart disease (heart disease caused by hypertension) and diseases of the heart valves, especially the narrowing of the aortic valve (aortic stenosis), which is the blood outlet for out of the heart.
Diseases of the heart muscle or cardiomyopathies (dilated and hypertrophic types) are another cause of angina pectoris. These diseases are characterized, respectively, by an abnormal enlargement and thickening of the myocardium, causing an increase in the need for oxygen on the part of this muscle. Coronary arterial spasm (sudden and transient contraction of the muscle layer of the coronary artery), coronary tortuosity (crooked coronary arteries) and the intramyocardial bridge (abnormal path of the coronary artery inside the heart muscle, causing it to narrow during heart contraction ), are also causes of angina pectoris.
Many individuals describe the sensation as more of a discomfort or pressure than pain itself. Typically, angina pectoris is triggered by physical activity, lasts a few minutes (3 to 15 minutes) and disappears with rest or with the use of nitrates (coronary vasodilators). However, the pain can also reach the shoulders or radiate from the inside of the upper limbs, back, neck, jaw or upper abdomen.