Coronary Artery Disease: Symptoms, Causes, Risks & Treatment

Coronary artery disease (CAD), also known as coronary heart disease or ischemic heart disease, is the most common type of heart disease. It occurs when a narrowing or blockage in your coronary arteries is caused by the buildup of cholesterol-containing deposits called plaque. 

Coronary arteries are the blood vessels responsible for supplying oxygen-rich blood to your heart muscle to keep it pumping. A complete blockage in the blood flow in coronary arteries can lead to a heart attack.

Disease Name	Coronary artery disease (CAD)
Alternative Name	Coronary Heart Disease or Ischemic Heart Disease
Symptoms	Angina, Discomfort in your left shoulder, Shortness of breath, Dizziness, Sweating
Causes	Atherosclerosis, Arrhythmia
Diagnosis	Electrocardiogram, Echocardiogram, Exercise stress test, Nuclear stress test
Treated By	Cardiologist
Treatment Options	Balloon Angioplasty and Stent Placement, Coronary Artery Bypass Graft Surgery, Enhanced External Counterpulsation

The arteries cannot supply enough oxygen-rich blood to your heart in coronary artery disease. You may experience no symptoms at first as plaque takes years to build up in your arteries. However, you may experience the following signs and symptoms of coronary heart disease as the arteries continue to become narrow:

1. Angina (Chest pain): characterised by heaviness, discomfort, tightness, burning, aching, pressure, numbness, squeezing, fullness, or a dull ache. 
2. Discomfort in your left shoulder, arms, jaw, back, and neck 
3. Shortness of breath
4. Dizziness
5. Sweating
6. Weakness

Women may also experience the symptoms mentioned above, but they are more likely to experience:

1. Nausea
2. Vomiting
3. Cold sweat
4. Jaw and upper back pain
5. Shortness of breath without chest pain
6. Unexplained anxiety
7. A feeling of indigestion or heartburn

Sometimes, you would not know that you have coronary heart disease until you get a heart attack. 

1. The most common cause of coronary artery disease is the cholesterol plaque buildup (atherosclerosis) in the inner layer of the coronary artery that starts as early as childhood. 
2. The plaque buildup restricts the free flow of blood through the arteries. 
3. Without enough oxygen-rich blood, the heart becomes weaker, leading to an irregular heartbeat (arrhythmia). 
4. If the plaque grows extremely large, it stops the blood flow to the heart muscle, causing a heart attack. 
5. In some cases, the plaque surface breaks or ruptures. As a result, the blood cells known as platelets clump together and try to repair the artery, forming a blood clot. The blood clot can block the artery, leading to a heart attack.

There are several risk factors for coronary artery disease, including:

1. High blood cholesterol levels
2. High blood pressure
3. Diabetes
4. Family history of heart disease
5. Smoking
6. Obesity
7. Man older than 45 years or post-menopausal woman
8. Unhealthy diet
9. Lack of exercise
10. High stress or depression
11. Excessive alcohol consumption
12. Sleep apnea (breathing is interrupted during sleep)

Although you can not prevent certain risk factors, such as genetics, older age, or a family history of heart diseases, you can prevent the modifiable risk factors by following these preventive tips:

1. Quit smoking
2. Maintain a healthy weight
3. Control conditions such as diabetes, cholesterol, and blood pressure
4. Exercise regularly
5. Eat low fat, low salt, fibre-rich diet
6. Limit your alcohol
7. Reduce and maintain stress level

The doctor will enquire about your symptoms and medical history, review the risk factors, and perform a physical test to diagnose coronary artery disease. The diagnostic tests include:

1. Electrocardiogram (ECG): The test records electrical signals as they pass through your heart, revealing evidence of a previous heart attack or one that’s progressing. 
2. Echocardiogram: The test uses sound waves to check the working of your heart’s structure and the overall activity of your heart. 
3. Exercise stress test: The doctor will ask you to walk on a treadmill or pedal a stationary bike to check how well your heart functions when working the hardest. The test detects angina and blockages in coronary arteries. 
4. Nuclear stress test: Uses radioactive material to check how well the blood flows into the heart muscle at rest and during activity. 
5. Coronary calcium scan: It measures the calcium level in the walls of your coronary arteries. 
6. Blood tests: The test checks cholesterol, glucose, triglycerides, lipoprotein, C-reactive protein, and HbA1c. 
7. Cardiac catheterisation: The doctor gently inserts a catheter into the heart’s blood vessel to evaluate the functioning of the heart and detect the presence of coronary artery disease. 
8. Computed tomography angiogram: The test uses a contrast dye to produce detailed images of your coronary arteries during a CT scan. 

When to See a Doctor?

You need immediate medical care if you think you have a heart attack. Symptoms include:

1. Chest pain, usually in the centre or left side of the chest
2. Shortness of breath
3. Discomfort in arms, shoulders, jaw, neck, or upper part of the stomach
4. Nausea, vomiting, dizziness, or cold sweat

Treatment for coronary artery disease generally includes lifestyle changes. The doctor may also prescribe certain medications or perform medical procedures if required. 

Lifestyle Changes

The following time-tested methods can reduce your risk of heart diseases:

1. Quit smoking
2. Limit your alcohol use
3. Eat a healthy diet
4. Exercise regularly
5. Maintain a healthy weight
6. Learn effective ways to manage your stress

Medications

Your provider may prescribe the following medications to treat coronary artery disease:

1. Reducing the risk of blood clots: anticoagulants like aspirin or antiplatelets
2. Lowering blood pressure: beta-blockers, calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors, or angiotensin II receptor blockers (ARBs)
3. Stopping angina: ranolazine or nitroglycerine
4. Lowering cholesterol levels: statins, niacin, bile acid sequestrants, or fibrates

Medical Procedures

Sometimes the doctor may need to perform medical procedures to treat heart disease. 

Balloon Angioplasty and Stent Placement

1. The doctor inserts a long, thin tube (a catheter) into the blocked or narrowed coronary arteries. 
2. He/she then passes a wire with a deflated balloon through the catheter. 
3. The doctor inflates the balloon, opening the artery for adequate blood flow. 
4. In many cases, the doctor may use a tiny tube called a stent and leave it in the artery to keep it open. 

Coronary Artery Bypass Graft (CABG) Surgery

1. The surgeon uses blood vessels from other parts of the body to create a new path for blood flow when there is a blockage in the coronary artery. 
2. The surgery is often recommended for people who have multiple narrowed coronary arteries. 

Enhanced External Counterpulsation (EECP)

1. The doctor uses inflatable cuffs to apply pressure to the blood vessels in your lower body.
2. The pressure helps increase blood flow to the heart and creates natural bypasses around blocked or narrowed coronary arteries. 
3. The procedure is recommended for chronic angina patients who cannot have an invasive procedure like surgery. 
4. The selection of the treatment approach is based on your condition and your doctor’s opinion. 

If not treated in time, coronary artery disease can lead to the following complications:

1. Angina (chest pain)
2. Heart attack (a condition that happens when the heart muscle does not get enough blood)
3. Heart failure (occurs when the heart does not pump blood as well as it should)
4. Arrhythmia (abnormal heart rhythm)
5. Sudden cardiac arrest (abrupt loss of breathing, heart function, and consciousness)
6. Cardiogenic shock (a life-threatening condition where the heart is unable to pump enough blood to meet the body’s needs)

Progression of Coronary Artery Disease

1. Stage 0: No visible plaque buildup in the coronary arteries.
2. Stage 1: Mild heart disease with less than 30 per cent blockage in one or two blood vessels. 
3. Stage 2: Moderate heart disease with a blockage between 30 to 49 per cent in one or two blood vessels or a mild blockage in three blood vessels.
4. Stage 3: Severe heart disease with more than 50 per cent blockage in one or two coronary arteries or 30 to 49 per cent blockage in three blood vessels.
5. Stage 4: Very severe heart disease with more than 50 per cent blockage in three or more blood vessels. 

While preparing for your doctor consultation, make sure to:

1. Take a prior appointment
2. Be aware of any pre-appointment restrictions
3. Make a list of the symptoms and your medical history
4. Find a friend or family member to accompany you
5. Make a list of the questions for the doctor

Here’s what you can ask your doctor during the visit:

1. What can be the possible cause of my symptoms?
2. What are the signs and symptoms that require emergency medical attention?
3. What diagnostic tests do I need to undergo?
4. Do I need to consult a specialist?
5. What are the treatment options available, and what do you recommend?
6. Am I the right candidate for surgery?

Here’s what you can expect from your doctor during the visit:

1. What are the symptoms, and when did you first experience those?
2. Do you have chest pain or face difficulty in breathing?
3. Does any of your family members have a history of heart problems?
4. Does exercise make the symptoms worse?
5. What medications do you take?
6. Do you have any other health conditions?
7. What is your daily diet?
8. Do you smoke?
9. Do you consume alcohol? If yes, how much?