GCSE Biology Revision "Cardiovascular Diseases"

Cardiovascular Diseases

• Definition: Diseases of the heart and blood vessels that are non-communicable (not infectious and cannot be passed from person to person)

Example Disease: Coronary Heart Disease

• Function of Coronary Arteries: Branch from the aorta to supply oxygen to heart muscle cells, used for respiration to provide energy for muscle contraction.

• What happens in coronary heart disease:

  • Layers of Fatty material buildup in coronary arteries leads to narrowing.

  • Causes reduced blood flow, results in decreased oxygen supply to heart muscle, potentially causing a heart attack due to lack of oxygen, can be fatal.

Treatments for Coronary Heart Disease

1. Statins:

   • drugs that reduces the levels of cholesterol in the blood, slow down the rate of fatty buildup in arteries.

   • Advantages: Effective in lowering the risk of coronary heart disease.

   • Disadvantages: Possible side effects, including liver problems.

2. Stents:

   • Tubes inserted into narrowed coronary arteries to keep them open.

   • Advantages: Restores normal blood flow through the artery/ regulates blood flow.

   • Limitations: a stent will not prevent other regions of the coronary arteries from narrowing, as it does not treat the underlying causes of the disease.

Heart Valve Diseases

• Types of Valve Issues:

  • Valves may not open completely, causing the heart to work harder to get the blood through causing (enlargement).

  • Leaky valves result in fatigue and weakness.

• Treatment Options:

  1. Mechanical Valves:

     • Longevity: Can last a lifetime.

     • Risks: Increased risk of blood clots; requires anti-clotting medication.

  2. Animal Valves (e.g., from pigs):

     • Longevity: Shorter lifespan than mechanical valves, may need replacement.

     • Advantages: No need for anti-clotting drugs.

Heart Failure

• Definition: Condition where the heart cannot pump enough blood throughout the body.

• Treatment Options:

  1. Donated Hearts or Heart/Lungs:

     • Challenges: Limited availability of donor organs; risk of organ rejection requiring immunosuppressants to prevent the donor heart from being rejected from the body’s immune system.

  2. Artificial Hearts:

     • Function: Temporary solution while waiting for transplants or to allow the heart to rest.

     • Risks: Increased risk of blood clots; not a long-term solution; limited duration of use.