Coronary Artery Disease (CAD)

Overview:

• Disease of the arteries supplying blood to the heart muscle.
• Also called coronary heart disease or ischemic heart disease.
• Main clinical presentations:
  • Angina pectoris (chest pain due to ischemia).
  • Myocardial infarction (heart attack) — complete blockage leading to tissue death.
  • Can lead to heart failure or arrhythmias.

Risk Factors:

• Hypertension.
• Gender: Males are at higher risk.
• Race: Caucasians may be more susceptible.
• Genetics and lifestyle: Obesity, smoking, poor diet, sedentary lifestyle.

Definitions of Arteriosclerosis and Atherosclerosis:

• Arteriosclerosis:
  • The umbrella term for the hardening of arteries.
  • Encompasses various changes in arterial walls, including atherosclerosis.
• Atherosclerosis:
  • A specific type of arteriosclerosis characterized by the buildup of atheromatous plaques (fatty deposits) within the arterial wall.

Pathophysiology of Arteriosclerosis:

• Over time, blood vessels become less capable of regeneration.
• Elastic fibers in arterial walls decrease with age:
  • Results in stiffening of arteries.
  • Reduced elasticity causes narrowing of the lumen (the blood vessel opening).
  • The lumen’s narrowing impairs vasodilation, making blood flow less adaptable.

Effects of Vessel Stiffening & Narrowing:

• Increased resistance causes higher blood pressure (hypertension).
• Progressive narrowing leads to reduced blood flow to tissues needing oxygen.
• Key tissues:
  • Kidneys, brain, and heart: Highly sensitive to hypoxia (low oxygen).
  • Insufficient oxygen: can cause dysfunction and tissue death.

Common Complications:

• Increased blood pressure with age, especially after 50+.
• In diabetes, high blood sugar damages vessel walls:
  • Accelerates narrowing (damage to vessel walls).
  • Can lead to ischemia, organ dysfunction, and amputations (e.g., in feet).

Aging & Vascular Changes:

• Natural decline in elasticity causes progressive narrowing.
• Lifestyle and disease (like diabetes) exacerbate the process.

Consequence:

• Progressive damage, leading to conduction system damage, dysrhythmias, and heart failure.
• Early detection and management of risk factors are essential to prevent adverse outcomes.

Summary:

Arteriosclerosis is a natural consequence of aging, involving stiffening and narrowing of arteries, which increases blood pressure and impairs tissue perfusion.

In high-risk groups like diabetics, vessel wall damage accelerates this process, leading to significant cardiovascular and organ health issues.

Recognizing these changes underscores the importance of managing risk factors for cardiovascular health.