CORONARY HEART DISEASE

CORONARY HEART DISEASE

1. CARDIOVASCULAR DISEASE

   • vascular disorders: stroke, varicose veins
   • coronary heart disease (CHD)
     • congenital
       • viral damage
         • atherosclerosis
           • angina myocardial infarction

2. PREVALENCE

   • 2nd most common cause of death worldwide
   • cause of greatest number of deaths in UK
   • greatest effect in 'Western cultures'

3. CHD attributable to risk factors?

   • ...physical inactivity (37%)
   • ...obesity (6%)
   • ...blood pressure >140/90mmHg (13%)
   • ...blood cholesterol >5.2mmol/l (46%)
   • ...smoking (19%)

4. ATHEROSCLEROSIS

   • formation of plaque of cells in an artery wall
   • initiated by damage to single-cell endothelium
     • mechanical
     • toxins
     • viral infection
     • metabolic stress e.g. hypercholesterolaemia

5. LOW DENSITY LIPOPROTEIN

   • ~600 cholesterol molecules
   • ~1000 cholesterol ester molecules

6. OCCLUSIVE CORONARY ATHEROSCLEROSIS

   • the aortic atheromatous plaque is thicker than the remaining media on the right. the plaque contains amorphous pink material with slit-like 'cholesterol clefts' of lipid material. there is overlying recent haemorrhage at the left.

7. FATE OF PLAQUE

   • increase in size to totally occlude artery
   • rupture and subsequent loss of cap leads to blockage elsewhere or formation of a clot at the plaque
   • haemorrhage due to lesion of vessel - aneurysm

8. CURRENT TREATMENT

   • PHARMACOLOGICAL
     • hypertension - lower stress of vessels
     • vasodilators - dilating arteries
     • b-blockers - reducing work
     • anticoagulants - embolism
     • statins - reduce cholesterol
   • LIFESTYLE/BEHAVIOUR
     • diet: reduce cholesterol intake, increase antioxidants and fibre
     • exercise
   • INVASIVE
     • by-pass surgery
     • angioplasty
     • repair-ruptured vessel
     • transplant

9. RECENT/CURRENT RESEARCH

   • inflammatory response
     • serum markers of inflammation: c-reactive protein, leukocyte count, cytokines
     • show qualitative relationship with severity and prognosis of disease
   • enhanced affect of statins
     • effect greater than expected by down regulation of cholesterol production alone
   • relevance of plasma triglyceride concentration

10. CURRENT/FUTURE THERAPY

    • increased use of ACE inhibitors - better control of hypertension
    • maximise use of statins - free radical scavengers and modulation of immune response
    • diet - homocysteine reduction: level homocysteine increases with cofactors vit b6 and folate missiong from methionine breakdown pathway
    • better diagnosis/prediction: e.g. c-reactive protein