Coronary Heart Disease: Causes, Symptoms, Diagnosis, Treatment, and Prevention
Known as coronary artery disease (CAD), coronary heart disease (CHD) affects the blood vessels that supply oxygen and nutrients to the heart. In CHD, these blood vessels become narrowed or blocked due to fatty deposits called plaque. As a result, chest pain, shortness of breath, and heart attacks can occur.
Causes of CHD
Atherosclerosis, or plaque buildup in the inner walls of the arteries, is the main cause of CHD. Plaque consists of cholesterol, fat, calcium, and other substances that circulate in the blood. Plaque can harden and narrow the arteries over time, making them less flexible and more vulnerable to damage. It is also possible for plaque to rupture and cause blood clots, preventing blood from flowing to the heart for a prolonged period of time.
Risk Factors for CHD
Some factors that increase the risk of developing CHD are:
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High blood pressure: This puts extra strain on the arteries and can damage their inner lining.
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High cholesterol: This contributes to the formation of plaque in the arteries.
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Diabetes: This affects the ability of the body to use sugar (glucose) and can increase the levels of triglycerides, a type of fat in the blood that can also form plaque.
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Smoking: This damages the blood vessels and reduces the amount of oxygen in the blood.
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Obesity: This increases the workload of the heart and the blood pressure, and can also lead to diabetes and high cholesterol.
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Physical inactivity: This lowers the levels of HDL (good) cholesterol, which helps remove LDL (bad) cholesterol from the arteries, and can also contribute to obesity, high blood pressure, and diabetes.
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Stress: This can raise the blood pressure and the heart rate, and can also trigger unhealthy behaviors such as smoking, drinking, and overeating.
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Alcohol: This can increase the blood pressure and the triglyceride levels, and can also damage the heart muscle.
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Family history: This increases the likelihood of inheriting genes that predispose to CHD.
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Age: This increases the wear and tear of the arteries and the risk of plaque formation.
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Gender: Men are more likely to develop CHD at an earlier age than women, who are protected by estrogen until menopause.
Symptoms of CHD
Symptoms may not be evident until the blood flow to the heart is significantly reduced or blocked by CHD. The most common symptom is angina, a type of chest pain or discomfort caused when the heart does not receive enough oxygen. Angina may feel like pressure, squeezing, tightness, heaviness, or burning in the chest. It may also radiate to the neck, jaw, shoulders, arms, or back. With rest or medication, angina usually subsides after physical activity, emotional stress, or exposure to cold or hot weather.
When the heart cannot pump enough blood to meet the body's needs, shortness of breath occurs, which can be accompanied by fatigue, weakness, dizziness, or fainting.
The most serious complication of CHD is a heart attack, which occurs when a blood clot completely blocks the blood flow to a part of the heart. The chest pain may be severe and sudden. It may last for more than 15 minutes without relief from rest or medication. Sweating, nausea, vomiting, irregular heartbeats, difficulty breathing, or loss of consciousness are also symptoms of a heart attack. Heart attacks are medical emergencies that require immediate treatment to prevent permanent heart damage or death.
Diagnosis of CHD
The doctor will ask about the symptoms, medical history, and risk factors, as well as perform a physical examination. They may also order certain tests to check the heart and blood vessels, such as:
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Electrocardiogram (ECG or EKG): This records the electrical activity of the heart and can detect abnormal rhythms, signs of damage, or reduced blood flow.
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Echocardiogram: This uses sound waves to create an image of the heart and can show its structure, function, and blood flow.
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Stress test: This measures the heart's response to exercise or medication that increases the heart rate and can reveal signs of reduced blood flow or damage.
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Coronary angiogram: This involves injecting a dye into the coronary arteries and taking X-ray images to show their location, size, and degree of blockage.
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CT scan: This uses X-rays to create detailed images of the heart and the coronary arteries and can detect calcium deposits that indicate plaque buildup.
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Blood tests: These measure the levels of cholesterol, triglycerides, glucose, and other substances in the blood that can affect the risk of CHD.
Treatment of CHD
The treatment of CHD aims to relieve the symptoms, improve the blood flow to the heart, prevent further damage, and reduce the risk of complications. The treatment may include:
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Among these are quitting smoking, limiting alcohol consumption, eating a healthy diet, exercising regularly, managing stress, and maintaining a healthy weight. Blood pressure, cholesterol, and glucose levels can be lowered by these, and the heart and blood vessels can be improved.
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Medicines: These include medications that lower blood pressure, cholesterol, and glucose levels, drugs that prevent blood clots, drugs that dilate the arteries and improve the blood flow, drugs that reduce the workload of the heart and the oxygen demand, and drugs that relieve chest pain. By controlling the risk factors, treating the symptoms, and reducing complications, these can be helpful.
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This involves interventions that open or bypass blocked or narrowed arteries and restore the flow of blood to the heart. These can provide immediate relief of symptoms and prevent or treat complications.
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As part of angioplasties and stentings, a thin tube (catheter) is inserted into the affected artery and inflated to compress the plaque and widen it. In order to prevent the artery from narrowing again, a mesh tube (stent) may be left in place.
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A coronary artery bypass graft (CABG) involves taking a healthy blood vessel from another part of the body and attaching it to the heart to create a new route for blood to flow around the blocked or narrowed artery.
Prevention of CHD
The best way to prevent CHD is to adopt a heart-healthy lifestyle and avoid or control the risk factors. Some preventive measures are:
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Do not smoke or use tobacco products, and avoid exposure to secondhand smoke.
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Limit alcohol intake to no more than one drink per day for women and two drinks per day for men.
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Eat a balanced diet that is low in saturated fat, trans fat, cholesterol, salt, and added sugars, and high in fruits, vegetables, whole grains, lean proteins, and healthy fats.
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Exercise for at least 30 minutes on most days of the week, or as recommended by the doctor.
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Manage stress by practicing relaxation techniques, such as deep breathing, meditation, yoga, or hobbies.
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Get enough sleep, at least seven to eight hours per night, and follow a regular sleep schedule.
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Check the blood pressure, cholesterol, and glucose levels regularly, and follow the doctor's advice on how to keep them within the normal range.
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Take the prescribed medications as directed, and do not stop or change them without consulting the doctor.
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Follow up with the doctor regularly, and report any new or worsening symptoms or concerns.
