What is Coronary Artery Disease?
Coronary artery disease (CAD), also called coronary heart disease, is the most common type of heart disease and the leading cause of death worldwide. CAD develops when the major blood vessels (coronary arteries) that supply your heart with blood, oxygen, and nutrients become damaged or diseased.
The disease typically develops over decades as cholesterol-containing deposits called plaques build up in your coronary arteries—a process called atherosclerosis. These plaques narrow the arteries, reducing blood flow to your heart muscle. Eventually, this decreased blood flow can cause chest pain (angina), shortness of breath, or other warning signs. A complete blockage can lead to a heart attack.
Understanding the Development
CAD begins when damage occurs to the inner layer of a coronary artery, sometimes as early as childhood. The damage may be caused by various factors including smoking, high blood pressure, high cholesterol, diabetes, or insulin resistance.
Once the inner wall of an artery is damaged, fatty deposits (plaque) made of cholesterol and other cellular waste products tend to accumulate at the site. This process is called atherosclerosis. If the surface of these plaques breaks or ruptures, blood cells called platelets will clump at the site to try to repair the artery, potentially blocking blood flow and leading to a heart attack.
Symptoms
CAD often develops over many years. You may not notice any symptoms until you have a significant blockage or a heart attack. Common symptoms of CAD include:
- Angina (chest pain or discomfort): May feel like pressure, squeezing, fullness, or pain in the center or left side of the chest. Often triggered by physical or emotional stress and goes away with rest.
- Shortness of breath: If your heart can't pump enough blood to meet your body's needs, you may develop shortness of breath or extreme fatigue with activity.
- Heart attack: A completely blocked coronary artery will cause a heart attack. Classic symptoms include crushing pressure in your chest and pain in your shoulder or arm, sometimes with shortness of breath and sweating.
Risk Factors
Risk factors for CAD include conditions and habits that increase your chance of developing the disease. Many risk factors can be controlled or modified:
Modifiable Risk Factors
- High blood pressure: Over time, damages artery walls
- High cholesterol: Particularly high LDL (bad cholesterol) and low HDL (good cholesterol)
- Smoking: Including exposure to secondhand smoke
- Diabetes: High blood sugar damages blood vessels
- Obesity: Excess weight increases strain on the heart
- Physical inactivity: Lack of exercise increases other risk factors
- Unhealthy diet: High in saturated fats, trans fats, salt, and sugar
- Stress: Unrelieved stress may damage arteries
- Excessive alcohol: Can raise blood pressure and cholesterol
Non-Modifiable Risk Factors
- Age: Risk increases with age
- Sex: Men generally have higher risk earlier in life; women's risk increases after menopause
- Family history: Especially if a close relative developed heart disease at an early age
- Race/ethnicity: Some groups have higher rates of risk factors
Diagnosis
Your doctor will ask about your medical history, conduct a physical examination, and may recommend one or more diagnostic tests:
- Electrocardiogram (ECG): Records electrical signals as they travel through your heart
- Echocardiogram: Uses sound waves to produce images of your heart
- Stress test: Measures how your heart responds during physical exertion
- Cardiac catheterization and angiogram: Shows blockages in your coronary arteries
- CT scan: Can detect calcium deposits in artery walls
- Blood tests: Check cholesterol, blood sugar, and markers of heart damage
Treatment and Management
Treatment for CAD involves lifestyle changes, medications, and sometimes procedures or surgery to improve blood flow to the heart.
Lifestyle Changes
- Quit smoking: Single most important step you can take
- Eat a heart-healthy diet: Focus on vegetables, fruits, whole grains, and lean proteins
- Exercise regularly: At least 150 minutes of moderate activity per week
- Lose excess weight: Even modest weight loss helps
- Manage stress: Find healthy ways to cope with stress
- Get quality sleep: Aim for 7-9 hours per night
- Limit alcohol: No more than moderate amounts if you drink
Medications
- Cholesterol-lowering drugs: Statins and other medications reduce plaque buildup
- Aspirin: Helps prevent blood clots (unless contraindicated)
- Beta blockers: Slow heart rate and decrease blood pressure
- Calcium channel blockers: Relax and widen blood vessels
- Nitroglycerin: Temporarily widens arteries for symptom relief
- ACE inhibitors and ARBs: Help lower blood pressure
Procedures and Surgery
- Angioplasty and stenting: Opens blocked arteries with a balloon and places a mesh tube to keep the artery open
- Coronary artery bypass surgery (CABG): Creates a new pathway for blood to flow around a blockage
- Enhanced external counterpulsation: Non-invasive treatment that may improve blood flow
Prevention
The same lifestyle habits that help treat CAD can also prevent it from developing in the first place. A heart-healthy lifestyle is your best defense against CAD.
If you have risk factors such as high blood pressure, high cholesterol, or diabetes, work with your healthcare provider to keep them under control. Regular checkups can help detect problems early when they're easier to treat.
When to Seek Emergency Help
If you think you're having a heart attack—chest pain or discomfort that lasts more than a few minutes or goes away and comes back, pain in other areas like arms, back, neck, jaw or stomach, shortness of breath, cold sweat, nausea, or lightheadedness—call emergency services immediately.
Don't try to drive yourself to the hospital. Emergency medical personnel can begin treatment as soon as they arrive and are trained to revive someone whose heart has stopped.