Coronary artery disease (CAD)
1. What Are the Coronary Arteries?
The coronary arteries are blood vessels that supply blood to the heart. Like other organs in the body, the heart muscle needs an adequate supply of oxygen-rich blood to function. These blood vessels run along the surface of the heart and branch into smaller vessels that supply the heart muscle.
1. What Are the Coronary Arteries?
There are two main coronary arteries that supply the heart: the right coronary artery and the left coronary artery.
The left coronary artery originates from the left main coronary artery (LMCA) and divides into two major branches: the left anterior descending artery (LAD) and the left circumflex artery (LCx), which supply blood to the left side of the heart, which is also responsible for pumping blood to the organs throughout the body. The right coronary artery (RCA) supplies blood to the right side of the heart and the heart's pacemaking structures.
3. Why Are the Coronary Arteries Important?
Because the coronary arteries supply blood to the heart muscle, while the heart pumps blood to the organs throughout the body, any condition affecting the coronary arteries that reduces blood flow can lead to myocardial infarction and death.
The most common coronary artery disease is caused by atherosclerosis. Atherosclerotic plaque in the coronary artery wall gradually narrows the arterial lumen and may progress to complete blockage.
4. What Is Coronary Artery Disease?
Coronary artery disease, also known as coronary heart disease, is characterized by inflammation and the accumulation of fat within the walls of the coronary arteries. This process begins at a young age, gradually progresses, and eventually forms atherosclerotic plaques that narrow the arterial lumen and obstruct blood flow.
5. Who Is at Risk of Coronary Artery Disease?
Risk factors for coronary artery disease include:
- Smoking
- Dyslipidemia (elevated LDL cholesterol, elevated blood triglycerides, and low HDL cholesterol)
- Hypertension
- Physical inactivity
- Obesity
- A diet high in saturated fat
- Diabetes mellitus
- Having a close blood relative with coronary artery disease
Limiting these risk factors is key to reducing the risk of coronary artery disease.
5.1. What Symptoms Do People With Coronary Artery Disease Have?
Symptoms depend on the severity of coronary artery narrowing. Some people have no symptoms, while others may experience mild chest pain or severe chest pain.
When the heart muscle does not receive enough blood, the patient may experience chest pain. When blood flow to the heart muscle is completely interrupted, myocardial infarction occurs and the heart muscle begins to die. However, some people experience myocardial infarction without any symptoms, which is commonly referred to as a “silent myocardial infarction.”
Symptoms of coronary artery disease include:
- A feeling of heaviness, squeezing, pressure, or pain in the center of the chest
- Pain radiating to the shoulder, arm, neck, jaw, or back
- Shortness of breath
- Fatigue or weakness
6. How Is Coronary Artery Disease Diagnosed?
In addition to a thorough medical history and physical examination by a physician, patients may need to undergo several tests.
Electrocardiography (ECG): Sensors are attached to the patient's skin to detect the heart's electrical activity, helping identify abnormalities in heart rhythm and possible myocardial injury.
Stress testing: The patient exercises on a treadmill while cardiac activity is monitored. Stress tests help diagnose coronary artery disease and determine a safe exercise threshold. Stress testing can also be performed while the patient is at rest by using specific medications to induce cardiac stress.
Myocardial perfusion imaging: The patient is administered a radiotracer, and a specialized imaging system records the uptake of the tracer by the heart muscle, thereby showing areas of normal or damaged myocardium.
Coronary angiography: During this procedure, physicians advance a catheter into the coronary arteries and inject contrast material. X-ray imaging is then used to clearly visualize areas of narrowing, blockage, or other abnormalities in the coronary arteries.
7. Treatment of Coronary Artery Disease
Treatment may include:
- Modification of risk factors: Modifiable risk factors such as smoking, dyslipidemia, elevated blood glucose, physical inactivity, unhealthy eating habits, overweight, and hypertension should be treated and addressed through lifestyle changes.
- Oral medications: Medications that may be used by physicians to treat coronary artery disease include:
- Antiplatelet medications: These medications reduce the ability of the blood to form clots, such as aspirin, clopidogrel, and ticagrelor.
- Lipid-lowering medications: These medications help reduce harmful blood lipids, particularly LDL cholesterol. Statins are commonly used, including simvastatin, atorvastatin, and rosuvastatin.
- Antihypertensive medications: These medications help control blood pressure and include various drug classes with different mechanisms of action.
- Percutaneous coronary intervention (PCI): This is a group of interventional procedures used to improve coronary blood flow. These procedures include:
- Balloon angioplasty: During balloon angioplasty and coronary stent placement, the operator inflates a specially designed small balloon inside the coronary artery to open the narrowed or blocked area.
- Coronary stent placement: The operator advances a small metal mesh tube (stent) through the narrowed section of the coronary artery and expands the stent to widen the arterial lumen. The stent remains permanently in the coronary artery.
- Atherectomy: The operator uses a specialized device to cut or remove atherosclerotic plaque from within the coronary artery.
- Coronary artery bypass grafting (CABG): The surgeon uses a segment of an artery taken from the chest or a vein taken from the leg to create a bypass that supplies blood to the coronary artery beyond the blocked segment. The surgery may involve one, two, or multiple bypass grafts.
The information above is for reference purposes only and is not intended as medical advice. Please contact your doctor for detailed medical consultation.