This deep dive covers Coronary Heart Disease (CHD) within The Heart and Circulation for GCSE Biology. Heart structure, cardiac cycle, blood vessels, double circulation, heart rate control, and cardiovascular health It is section 9 of 15 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 9 of 15
Practice
20 questions
Recall
25 flashcards
💔 Coronary Heart Disease (CHD)
Coronary heart disease is caused by a build-up of fatty deposits (atheroma) inside the coronary arteries — the blood vessels that supply the heart muscle with oxygen and glucose.
What Happens
- Fatty material (including cholesterol) builds up on the artery walls
- The lumen (space inside the artery) becomes narrower
- Less blood flows through → less oxygen reaches the heart muscle
- This can cause angina (chest pain during exercise) or a heart attack (if the artery becomes completely blocked)
Risk Factors
- Smoking — damages artery walls, making fatty deposits more likely
- High-fat diet — raises blood cholesterol levels
- Lack of exercise — reduces cardiovascular fitness
- Obesity — linked to high blood pressure and cholesterol
- Genetic factors — some people inherit a higher risk
Treatments
| Treatment | How It Works | Limitations |
|---|---|---|
| Stents | A wire mesh tube inserted into the narrowed artery to hold it open, restoring blood flow | Risk of blood clots forming on the stent; may need replacing |
| Statins | Drugs that reduce blood cholesterol, slowing further fatty deposit build-up | Must be taken long-term; can have side effects (muscle pain, liver problems) |
| Heart valves | Faulty or leaking valves replaced with mechanical (metal) or biological (animal tissue) valves | Mechanical valves require blood-thinning drugs for life; biological valves wear out |
| Heart transplant | Entire heart replaced from a donor — used for severe heart failure | Donor shortage; immune rejection risk; lifelong immunosuppressants needed |
Exam essential: Know the difference between stents (physical — holds artery open) and statins (chemical — lowers cholesterol). Examiners often ask you to compare them.