Tension angina: general information

Angina pectoris is a clinical syndrome characterized by chest discomfort or pressure due to transient myocardial ischemia. These symptoms usually worsen with exertion and disappear with rest or with sublingual nitroglycerin. Diagnosis is based on clinical presentation, ECG, and myocardial imaging. Treatment may include nitrates, beta-blockers, calcium channel blockers, and coronary angioplasty or coronary artery bypass grafting.

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Causes of angina pectoris

Angina pectoris develops when the work of the myocardium and, as a result, its need for oxygen exceed the ability of the coronary arteries to provide adequate blood flow and deliver a sufficient amount of oxygenated blood (which occurs when the arteries are narrowed). The cause of narrowing is most often atherosclerosis, but spasm of the coronary artery or (rarely) its embolism are possible. Acute coronary thrombosis leads to the development of angina pectoris if the obstruction of blood flow is partial or transient, but this condition usually leads to the development of myocardial infarction.

Since myocardial oxygen demand is determined primarily by heart rate, systolic wall stress, and contractility, coronary artery stenosis usually results in angina, which occurs during exercise and is relieved at rest.

Angina pectoris: causes

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Symptoms of angina pectoris

The main symptom of angina pectoris is the occurrence of pain (unpleasant sensations) in the chest during physical exertion and their rapid disappearance at rest, after the load is stopped. In most cases, the duration of angina pectoris is from 1 to 5 minutes (often 1-3 minutes, depending on how quickly the patient stops the load). A feeling of squeezing, heaviness, distension, burning behind the breastbone is typical (these sensations are conventionally designated by the term "anginal pain"). Typical irradiation of pain is to the left and along the inner surface of the left arm. However, atypical variants of the nature, localization and irradiation of pain may also be observed. The main sign is the connection with physical exertion. Of additional importance is the clear effect of taking nitroglycerin (especially the effect of prophylactic nitroglycerin - before exercise).

Angina pectoris is also called stable angina. This emphasizes its reproducible nature. After establishing the presence of angina pectoris in a patient, it is necessary to determine the functional class (FC) of angina:

• I FC - "latent" angina. Attacks occur only under extreme stress. It is very difficult to clinically diagnose latent angina; it is necessary to use instrumental research methods.
• II FC - attacks of angina occur with normal exertion: when walking quickly, when climbing stairs (more than 1 floor), with accompanying unfavorable factors (for example, with psycho-emotional stress, in cold or windy weather, after eating).
• III FC - a sharp limitation of physical activity. Attacks occur with minor loads: when walking at an average pace of less than 500 m, when climbing stairs to the 1st floor. Rarely, attacks occur at rest (usually in a lying position or under psycho-emotional stress).
• IV FC - inability to perform any, even minimal, load without developing angina. Attacks of angina at rest. Most patients have a history of myocardial infarction, signs of circulatory failure.

Angina pectoris: symptoms

Diagnosis of angina pectoris

In typical ("classical") angina, the diagnosis is completely established based on the anamnesis. In atypical manifestations ("atypical pain syndrome"), when there is no clear connection with the load, the diagnosis remains presumptive. In atypical manifestations, additional instrumental research methods are necessary to clarify the diagnosis. The main method of documenting myocardial ischemia is a test with physical activity. In cases where the patient is unable to perform physical activity, pharmacological tests, cardiac pacing, or daily ECG monitoring are used.

Angina pectoris: diagnostics

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Treatment of angina pectoris

Modifiable risk factors should be eliminated as much as possible. People with nicotine dependence should stop smoking: after 2 years of smoking cessation, the risk of myocardial infarction decreases to the level of patients who have never smoked. Appropriate treatment of hypertension is necessary, since even moderate hypertension increases the workload of the heart. Weight loss (even as the only modifiable factor) often reduces the severity of angina. Sometimes, treatment of even mild left ventricular failure leads to a noticeable reduction in the severity of angina. Paradoxically, digitalis preparations sometimes increase angina, possibly due to increased myocardial contractility and the corresponding increase in oxygen demand, or due to an increase in arterial tone (or both).

Angina pectoris: treatment

Prognosis of angina pectoris

The main adverse outcomes are unstable angina, myocardial infarction, and sudden death due to the development of arrhythmia.

The annual mortality rate is approximately 1.4% in patients with angina pectoris who have no history of myocardial infarction, a normal resting ECG, and normal blood pressure. However, women with coronary artery disease tend to have a worse prognosis. The mortality rate is approximately 7.5% when systolic hypertension is present, 8.4% when ECG abnormalities are present, and 12% when both are present. Type 2 diabetes mellitus nearly doubles the mortality rate in each of these groups.

The prognosis worsens with increasing age, progression of angina symptoms, presence of anatomical lesions, and decreased ventricular function. Pathology of the left main coronary artery or proximal left anterior descending artery indicates a particularly high risk. Although the prognosis correlates with the number and severity of coronary artery lesions, it is much better in patients with stable angina, even in cases of three-vessel disease, provided that the ventricles function normally.