Angina: Causes, Symptoms, and Treatment
Angina is a common condition that affects millions of people worldwide. It is a type of chest pain that occurs when the heart muscle does not get enough oxygen-rich blood. Angina can be a sign of a serious heart problem, such as coronary artery disease, which is the leading cause of death in many countries. In this article, we will explore the causes, symptoms, types, diagnosis, treatment, and prevention of angina.
Causes of Angina
Angina is caused by reduced blood flow to the heart muscle. Blood carries oxygen, which the heart muscle needs to survive. When the heart muscle is not getting enough oxygen, it causes a condition called ischemia. Ischemia can result in chest pain or discomfort, which is called angina.
The most common cause of reduced blood flow to the heart muscle is coronary artery disease (CAD). CAD is a condition in which the arteries that supply blood to the heart become narrowed or blocked by fatty deposits called plaque. Plaque can build up over time due to factors such as high cholesterol, high blood pressure, smoking, diabetes, obesity, and family history. Plaque can also rupture and form a blood clot that can block the artery completely. This can lead to a heart attack, which is a life-threatening emergency.
Other causes of reduced blood flow to the heart muscle include abnormal heart rhythms, heart valve problems, heart failure, and anemia. These conditions can affect the pumping function of the heart or the amount of oxygen in the blood.
Symptoms of angina
The main symptom of angina is chest pain or discomfort. The chest pain or discomfort may feel like:
- Burning
- Fullness
- Pressure
- Squeezing
Pain may also be felt in the arms, neck, jaw, shoulder, or back. Other symptoms of angina include:
- Dizziness
- Fatigue
- Nausea
- Shortness of breath
- Sweating
The severity, duration, and type of angina can vary. Some people may experience mild or occasional angina, while others may have severe or frequent angina. Some people may have no symptoms at all, which is called silent ischemia. Silent ischemia can be dangerous because it can lead to a heart attack without warning.
Types of angina
There are different types of angina depending on the cause and whether rest or medication relieves symptoms.
Stable angina:
This is the most common type of angina. It usually occurs during physical or mental exertion, such as walking, climbing stairs, or stress. It follows a predictable pattern in terms of frequency, intensity, and duration. It typically lasts for a few minutes and goes away with rest or nitroglycerin (a medication that widens the blood vessels and increases blood flow to the heart). Stable angina does not usually indicate an imminent heart attack, but it indicates that there is underlying CAD that needs to be treated.
Unstable angina:
This is a more serious type of angina that requires immediate medical attention. It occurs unpredictably and often at rest or with minimal exertion. It may be severe and last longer than stable angina (more than 15 minutes). It may not go away with rest or nitroglycerin. It may indicate that a plaque has ruptured and formed a blood clot that is partially blocking an artery. This can lead to a heart attack if the blood flow is not restored quickly. Unstable angina is considered a medical emergency and should be treated as such.
Variant angina:
This is a rare type of angina that is caused by a spasm of a coronary artery that temporarily reduces blood flow to the heart muscle. It usually occurs at rest and often at night. It may be triggered by factors such as smoking, cold weather, drugs, or emotional stress. It may cause severe chest pain that may be relieved by nitroglycerin or other medications that prevent or treat spasms. Variant angina may also increase the risk of abnormal heart rhythms or sudden cardiac death.
Refractory angina:
This is a chronic type of angina that persists despite optimal medical therapy and lifestyle changes. It may limit the quality of life and daily activities of the affected person. It may be caused by severe CAD that cannot be treated by conventional methods such as angioplasty or bypass surgery. It may also be caused by microvascular disease, which is a condition in which the small blood vessels in the heart are damaged or dysfunctional. Refractory angina may require alternative treatments such as spinal cord stimulation or gene therapy.
Diagnosis of angina
The diagnosis of angina is based on the medical history, physical examination, and various tests that can assess the function and structure of the heart and its arteries.
Some of the tests that may be used to diagnose angina include:
Electrocardiogram (ECG):
This is a test that records the electrical activity of the heart and can detect when the heart muscle is deprived of oxygen. It can also show signs of a previous or current heart attack, abnormal heart rhythms, or heart enlargement.
Blood tests:
These are tests that measure the levels of certain substances in the blood that can indicate heart damage, inflammation, or risk factors for CAD. Some of the blood tests that may be used to diagnose angina include troponin, creatine kinase-MB, C-reactive protein, lipid profile, and blood glucose.
Stress test:
This is a test that measures how the heart responds to physical or pharmacological stress. It can show signs of ischemia, such as changes in the ECG, blood pressure, or heart rate. It can also evaluate the exercise capacity and prognosis of the person with angina. Some of the types of stress tests that may be used to diagnose angina include treadmill tests, bicycle tests, nuclear stress tests, and stress echocardiograms.
Chest X-ray:
This is a test that uses radiation to produce images of the chest and its organs. It can show signs of heart enlargement, fluid accumulation in the lungs, or other conditions that may cause or complicate angina.
Echocardiogram:
This is a test that uses sound waves to create images of the heart and its valves. It can show how well the heart pumps blood, how thick or thin the heart muscle is, how well the valves open and close, and whether there are any defects or abnormalities in the heart structure. It can also detect signs of ischemia, such as reduced blood flow or wall motion abnormalities.
Coronary Angiogram:
This is a test that uses a dye and X-ray to visualize how well the blood flows through the arteries in the heart. It can show the location and severity of any blockages or narrowing in the coronary arteries. It can also help to plan the best treatment option for angina, such as angioplasty, stenting, or bypass surgery.
Treatment of angina
The treatment of angina aims to relieve symptoms, prevent complications, and improve the quality of life and prognosis of the affected person. The treatment may involve a combination of medications, procedures, and lifestyle changes.
Some of the medications that may be used to treat angina include:
Nitrates: These are drugs that widen the blood vessels and increase blood flow to the heart muscle. They can relieve chest pain quickly and prevent angina attacks. They can be taken as tablets under the tongue (sublingual), as sprays, patches, or ointments on the skin (transdermal), or as pills (oral). Some examples of nitrates are nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate.
Antiplatelet drugs: These are drugs that prevent blood clot formation by inhibiting platelet aggregation. They can reduce the risk of heart attack or stroke in people with angina. They are usually taken as pills (oral). Some examples of antiplatelet drugs are aspirin, clopidogrel, ticagrelor, and prasugrel.
Beta-blockers: These are drugs that block the effect of adrenaline hormones on the heart and blood vessels. They can slow down the heart rate, lower the blood pressure, and reduce the oxygen demand of the heart muscle. They can relieve chest pain and prevent angina attacks. They can also reduce the risk of abnormal heart rhythms or sudden cardiac death in people with angina. They are usually taken as pills (oral). Some examples of beta blockers are metoprolol, atenolol, bisoprolol, and propranolol.
Statins: These are drugs that lower blood cholesterol levels by inhibiting an enzyme involved in cholesterol synthesis. They can reduce the formation and progression of plaque in the coronary arteries and improve their function. They can also reduce inflammation and stabilize plaque rupture. They can lower the risk of heart attack or stroke in people with angina. They are usually taken as pills (oral). Some examples of statins are atorvastatin, simvastatin, rosuvastatin, and pravastatin.
Calcium channel blockers: These are drugs that widen the blood vessels and relax the smooth muscle cells in their walls. They can increase blood flow to the heart muscle and reduce its oxygen demand. They can relieve chest pain and prevent angina attacks. They can also treat variant angina caused by coronary artery spasm. They are usually taken as pills (oral). Some examples of calcium channel blockers are amlodipine, diltiazem, verapamil, and nifedipine.
Lifestyle Changes for Angina
Angina is a type of chest pain that occurs when the heart muscle does not get enough oxygen-rich blood. It can be a sign of a serious heart problem, such as coronary artery disease, which can increase the risk of heart attack or stroke. Therefore, it is important to make some lifestyle changes that can help with angina and prevent complications. Some of the lifestyle changes that can help with angina are:
- Having a balanced diet: Eating a variety of foods that are low in saturated fat, salt, and sugar, and high in fiber, fruits, vegetables, and whole grains can help lower cholesterol, blood pressure, and blood sugar levels, which are risk factors for angina and heart disease.
- Cutting down on alcohol: Drinking too much alcohol can raise blood pressure and damage the heart muscle, which can worsen angina symptoms and increase the risk of heart problems. It is recommended to limit alcohol intake to no more than 14 units a week for both men and women.
- Stopping smoking: Smoking damages the lining of the arteries and makes them more likely to become narrowed or blocked by plaque. This reduces blood flow to the heart and causes angina. Quitting smoking can improve blood circulation and oxygen delivery to the heart, as well as lower the risk of heart attack or stroke.
- Losing weight if overweight: Being overweight or obese puts extra strain on the heart and increases blood pressure and cholesterol levels, which can worsen angina symptoms and increase the risk of heart problems. Losing weight can reduce the workload on the heart and improve blood flow to the heart muscle.
- Exercising regularly: Physical activity can strengthen the heart muscle and make it more efficient at using oxygen. It can also lower blood pressure, cholesterol, and blood sugar levels, which are risk factors for angina and heart disease. Exercise can also relieve stress and improve mood, which can benefit people with angina. It is advised to do at least 150 minutes of moderate-intensity exercise a week, such as brisk walking, cycling, or swimming. However, it is important to start slowly and gradually increase the intensity and duration of exercise, as well as take regular breaks and use nitroglycerin medicine if needed to prevent or relieve chest pain.
- Practicing stress-relieving techniques: Stress can trigger or worsen angina symptoms by increasing blood pressure and heart rate, as well as causing emotional distress. Therefore, it is important to find healthy ways to cope with stress, such as relaxation techniques (e.g., breathing exercises, meditation, yoga), hobbies (e.g., reading, gardening, music), or talking to someone (e.g., family, friends, counselor).
These lifestyle changes can help improve angina symptoms, prevent complications, and improve the quality of life and prognosis of people with angina. However, they are not a substitute for medical treatment. People with angina should also follow their doctor’s advice on taking medicines or undergoing procedures that can treat the underlying cause of angina and reduce the risk of serious problems like heart attack or stroke.
