The leading cause of death in India is cardiovascular disease, with coronary artery disease topping the list. Find out everything you need to know about this condition, including its causes, risk factors, prevention, diagnosis, and treatment.
What is coronary artery disease?
Coronary artery disease (CAD) is when the coronary arteries (arteries that supply oxygenated blood to the heart) become narrow due to a buildup of plaque. As a result, the heart receives less blood supply, which can lead to a heart attack.
What is atherosclerosis?
Atherosclerosis is the gradual formation and deposition of plaque in the innermost layer of an artery. This process takes years and can be divided into:
- Fatty streaks: These are the earliest indications of atherosclerosis. Fat molecules start accumulating inside the blood vessels and activating your body’s defence mechanisms. Your white blood cells come to this area in response and surround the fat molecules, which further aggravates the inflammation in your blood vessels
- Stable plaque formation: As the above process continues, fat molecules and WBCs continue to get deposited in this area and are surrounded by scar tissue (‘fibrous cap’). This can bulge into the lumen of the artery and cause it to become narrower, thereby reducing the blood flow to the heart
- Unstable or ‘high-risk’ plaque formation: As inflammation continues, the plaque becomes unstable and has a high risk of rupturing. When this happens, it can lead to a heart attack or sudden death
What are the risk factors for coronary artery disease?
You’re at an increased risk of developing coronary artery disease if:
- You’re a man over the age of 45 years
- You’re postmenopausal (for females)
- Your cholesterol levels are high (specifically, high LDL levels and low HDL levels)
- Your blood pressure is higher than normal
- You suffer from diabetes
- You’re overweight or obese
- You lead a sedentary lifestyle
- You smoke regularly
- You have a family member suffering from heart disease
- You have high stress levels
What are the symptoms of CAD?
You may experience:
- Angina pectoris: This is the medical terminology for chest pain associated with heart disease. Characteristics of angina include :
- Constricting or squeezing type of chest pain
- Radiating to the arm, throat, jaw or back
- Lasting for around 5 minutes
- May be provoked by exercise, excitement, stress, cold weather or even eating
- Relieved with rest
- Easy fatigability that gets worse with exertion and is relieved on taking rest
- Heart attack: When there is a severe obstruction of the coronary arteries, it can lead to a heart attack. Symptoms of a heart attack are similar to angina, except that
- It usually lasts for more than 20 minutes
- It increases in intensity
- It does not get better with rest
It is accompanied by:
- Anxiety
- Sweating
- Palpitations
- Breathlessness
- Fainting
- Nausea and vomiting
Women tend to experience less typical symptoms of heart attacks such as:
- Pain in the neck, jaw or abdomen
- Heartburn
- Anxiety
- Sweating
If you’re experiencing any of the above symptoms, go to the hospital immediately.
How is CAD diagnosed?
Your doctor performs the below test:
- ECG (Electrocardiography): In this, you’re connected to 12 leads (electrodes) that measure the electrical activity of your heart and detect any irregularities or abnormalities
- Cardiac stress test (treadmill test): In this, you will be asked to walk on a treadmill as an ECG records your heart activity. It’s done in case you’re experiencing any symptoms or have a family history of the disease. It’s important to note that your doctor will not prescribe this if you have an ongoing episode of a heart attack, uncontrolled or severe symptoms of heart disease, or advanced heart failure
- Stress echocardiography: This combines the treadmill stress test with echocardiography to capture the dynamic motions of your heart
- Cardiac catheterisation and angiogram: If you have a strongly positive stress test and your doctor thinks you require some sort of intervention, your doctor can prescribe this procedure. Your doctor inserts a long flexible tube through one of the blood vessels in your groin and guides it into your heart. They then inject a dye through this tube to visualise the blood supply to your heart and detect any blockage.
- Laboratory tests: These include a blood test to detect blood cholesterol levels, markers that indicate any injury or damage to heart, blood sugar levels
How is CAD treated?
Your doctor will recommend a combination of medicines and lifestyle changes to decrease your risk of developing a full-fledged heart attack. These includes:
- Drugs: These drugs can relieve your symptoms and prevent your disease from getting worse. They includes:
- Nitrates:
These drugs cause your blood vessels to dilate and reduce the blood pressure and workload of your heart, as well as provide greater oxygen to your heart muscles. These tablets can be placed on your tongue whenever you’re experiencing symptoms and they usually relieve the pain within 2-3 minutes
- Beta blockers:
These reduce the workload on the heart by blocking the beta receptors, causing it to beat more slowly as well as reducing the blood pressure
- Calcium channel blockers:
They prevent the entry of calcium into the heart and blood vessels and reduce the workload on the heart, causes causing it to beat more slowly and reducing your blood pressure
- Potassium channel activators:
These drugs cause the potassium channels to open and cause blood vessels to relax
- Other drugs:
Some drugs that help relieve the symptoms and prevent the complications of CAD are:
- Low dose aspirin
- Clopidogrel
- Statins: These reduce the levels of ‘bad’ cholesterol in the body
- Lifestyle modifications: Your doctor will advise you to eat a healthy diet, maintain a normal weight and bring your blood pressure, cholesterol and glucose levels under control (see section under ‘How can I prevent CAD?’).
- Surgery
When do I need surgery for coronary artery disease?
If you have a severe block in your coronary artery, you’ll be asked to undergo
- Angioplasty: Your doctor introduces a thin, long tube (catheter) through a blood vessel in your groin or arm and guides it to your heart. A radiopaque dye is injected to visualise the site of the block and a small balloon is inflated at the site which widens the block and restores the blood flow
- Coronary artery bypass grafting (CABG): In this, the blocked artery is ‘bypassed’ and a new connection is made to restore blood flow to your heart
How can I prevent coronary artery disease?
You can make simple lifestyle modifications to decrease your risk. These include:
- Bringing your blood pressure under control
- Controlling your cholesterol levels (reducing the ‘bad’ cholesterol and increasing the levels of ‘good’ cholesterol in your body)
- Controlling your diabetes
- Quitting smoking
- Consume alcohol in moderation
- Exercising regularly
- Getting routine health check-ups
- Reducing stress by meditating, doing breathing exercises, and yoga
What are the complications of a heart attack?
The Complications of a heart attack include:
- Heart failure
- Rupture of your heart wall
- Various types of arrhythmias, or irregular rhythm patterns in your heart
- Formation of blood clots in your body
- Stroke
- Aneurysm, or dilatation of your heart
- Increased chances of getting subsequent heart attacks
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