OVERVIEW OF CORONARY ARTERY DISEASE
I. What is Coronary Artery Disease (CAD)?
Coronary Artery Disease (CAD), also known as ischemic heart disease (IHD), is a condition in which damaged coronary arteries struggle to supply the heart with enough blood, oxygen and nutrients. Reduced blood flow to the heart can cause chest pains (angina), heart attacks (myocardial infarction), and in extreme cases, death.
+ Clinical symptoms: patients usually experience left-side chest pain, patients are usually fatigued.
+ Consequences: reduced blood flow to the heart, heart failure, acute myocardial infarction (AMI),…
Main causes of coronary artery insufficiency
1. Atherosclerosis: is the most frequent cause. The plaque is made up of deposits of cholesterol, triglyceride, calcium, and other substances that can build up in the bloodstream. Such plaque buildup, or atherosclerosis, cause the inside of the arteries to narrow over time, which can partially or totally block the blood flow.
Coronary artery disease is caused by the buildup of plaques in the arteries
2. Ulcerated plaque in coronary arteries: Soft and unstable plaque may trigger the formation of blood clots. When these blood clots travel to narrow parts of the arteries, thrombosis may occur and drastically affect blood flow to the heart.
3. Spontaneous coronary artery dissection (SCAD): occurs when the inner lining of a coronary artery becomes damaged, leading to a separation between the layers of the artery wall. This separation can form at the site where the coronary artery originates from the aorta or between the layers of the artery wall. As a result, normal blood flow is disrupted, and some blood flows into the tears instead of nourishing the heart muscle. Consequently, the heart muscle does not receive the adequate blood supply it needs.
4. Endothelial dysfunction: Impairment of the normal functions of the endothelium, the innermost lining of blood vessels, can cause arteries to narrow. Endothelial dysfunction typically restricts reproductive functions and increases vasoactive hormones, which in turn compromises the vasoconstriction and vasodilation of arteries.
5. Myocardial bridging (MB).
6. Diabetes: is a prominent factor leading to coronary artery disease.
7. Coronary artery abnormality.
II. Coronary arteries structure
Illustration of the coronary arteries structure (American Heart Association).
Based on their structure, arteries possess different blood supply capabilities:
– The right coronary artery supplies blood to the right ventricle and 25 -35% to the left ventricle.
– The left anterior descending artery supplies 45 – 55% of blood to the left ventricle.
– The left circumflex artery supplies 15 – 25% of blood to the left ventricle.
Therefore, such differences mean that the clinical symptoms and emergency treatments upon arterial blood flow blockage will vary.
III. Risk factors of coronary artery disease
1. Age, gender.
2. Family medical history.
3. Unhealthy lifestyle.
4. High cholesterol (LDL, lipoprotein).
5. High blood pressure.
6. Diabetes (especially Type II).
IV. Symptoms of coronary artery disease
Symptoms of coronary artery disease usually occur when the arteries in the heart become narrowed or blocked, making it difficult to supply enough oxygen-rich blood to the organs and tissues in the body. These symptoms may include:
- Chest Pain (Angina): This is the most common symptom of coronary artery disease. Chest pain often occurs during physical exertion or stress and usually decreases with rest.
- Radiating Pain: Sometimes, pain from the chest can radiate to the shoulders, arms (especially the left arm), back, neck, or jaw.
- Shortness of Breath: This symptom increases with stress or strenuous activity. In addition to shortness of breath, patients often feel weak, fatigued, and unable to work or move.
- Fatigue, Dizziness: Patients may experience frequent or activity-induced fatigue and dizziness. Fatigue is often accompanied by lightheadedness or dizziness due to poor circulation and insufficient blood flow to the brain.
- Arrhythmias: Heart rhythm disturbances caused by coronary artery disease are somewhat similar to feelings of excitement or anxiety. Patients may notice a strong and rapid heartbeat, along with sensations of trembling, restlessness, anxiety, and palpitations.
Multiple authors ./.
References:
American Heart Association. (2020). What is Coronary Artery Disease?
https://www.heart.org/en/health-topics/consumer-healthcare/what-is-cardiovascular-disease/coronary-artery-disease
Mayo Clinic. (2022). Coronary artery disease.
https://www.mayoclinic.org/diseases-conditions/coronary-artery-disease/symptoms-causes/syc-20350613