CHD INTRO Flashcards
what are the 4 pathogenesis of IHD/ CHD
1- Atherosclerosis
2- Coronary Thrombosis
3- Coronary artery spasm
4- Coronary microvascular dysfunction
define myocardial ischaemia
- Reduced regional blood flow to the heart
- Imbalance between myodcardial demand/ supply
- Exertional demand vs. non-exertional supply ischaemia
define tissue ischaemia
reduced blood flow to an organ or tissue.
due to lack of O2 and nutrient supply.
and lack of washout of metabolic waste.
what are the types of tissue ischaemia?
reversible and irreversible tissue dammage.
what are the determinants of the extent of tissue damage caused by ischaemia? (3)
- the organ
- the duration and extent of reduced blood flow
- the existence of collateral circulation
what increases O2 demand?
wall stress
heart rate
contractility
what is the determinant of O2 supply?
near max at rest
define CHD
Coronary heart disease- pathological conditions characterised by a reduced or inadequate blood flow to the heart, usually due to an obstructive disease of the coronary arteries.
is CHD curable?
no but it can be prevented before you get it .. exercise/ diet etc
what is the single leading cause of death worldwide
CHD
(one of the leading causes of death and most common causes of premature death in the UK)
associated with high morbidity and cost
what is the 4 basic step disease process of CHD
1- Coronary artery obstruction or constriction
2- reduced regional blood flow to the heart
3- oxygen and nutrient deprivation and accumulation of toxic wastes
4- metabolic dysfunction/ contractile dysfunction/electrical instability/ myocardial cell death
what are the clinical manifestations of CHD?
1- angina pectoris (stable, variant or microvascular)
2- immediate or sudden cardiac death (do not see doctor)
3- acute coronary syndromes (acs) - see a doctor and are diagnosed- unstable angina/ acute myocardial infraction (NSTEMI, STEMI)
define Atherosclerosis
- a progressive, degenerative arterial disease characterised by asymmetric deposition of lipids and fibrous tissue on the inside walls of arteries.
- most common cause of CHD (>90%)
What is the disease process with atherosclerosis? (short)
inflammatory process, begins as a fatty streak
what is the 6 step disease process with atherosclerosis?
1- LDL deposition in sub-endothelial space
2-LDL oxidation and monocyte recruitment into sub- endothelial space
3- Macrophage differentiation +uptake of oxidized LDL
4- foam cell formation
5- SMC migration, proliferation & de-differentiation
6- fibrous plaque or atheroma