Chronic Stable angina Flashcards
what 4 processes occur in cellular injury
- decreased ATP
- membrane damage
- increased intracellular calcium
- increased oxygen derived free radicals
what does reduced ATP lead to?
- reduced action of Na-K-ATPase
- increased anaerobic glycolysis
- detachment of ribosomes
name 2 processes leading to membrane damage in cells
decreased ATP synthesis -> decreased phospholipid synthesis
raised intracellular Ca -> activates proteases and phospholipases
what does raised intracellular Ca lead to
activation of enzymes: ATPase phospholipase proteases endonucleases
what is ischaemia repercussion injury?
some reversibly injured cells can die after blood is restored to the myocardium. possibly caused by:
- Oxygen free radicals
- mitochondrial permeability transition
- Inflammation associated injury
- Complement proteins
what is athersclerosis
the accumulation of lipid and fibrous tissue within the intimate or arteries called plaques.
Chronically it can affect the media and the whole structure of the artery
describe the structer of atheromatous plaques
core –> mainly cholesterol (also cellular debris, crystals, foam cells)
fibrous cap –> collagen, elastin, sm muscle, proteoglycan
Cellular area of T lymphocytes and macrophages
describe the structure of a stable plaque
concentric
rich in fibrous storm
rich in smooth muscle
describe the structure of an unstable plaque
eccentric rich in lipids Macrophages ++ inflammation ++ endothelial cell injury
describe the consitutional risk factors for atherosclerosis
age
gender
FHx
describe some of the major risk factors for atherosclerosis
smoking
HTN
hyperlidiaemia
DM
describe some of the softer risk factors for atherosclerosis
Obesity
Personality/stress
Lack of exercise
infection
4 complications of coronary artery atheroma
- gradual narrowing of vessel
- ulceration of the plaque
- rupture and fissuring
- superimposed thrombosis
4 clinical features of atherosclerosis
- plaque rupture of coronary artery
- thrombosis
- occlusion of coronary artery
- MI
List some of the complications of MI
sudden death cardiac arrhythmias LV failure ventricular wall rupture Papillary muscle fibrosis/rupture Mural thrombosis Ventricular aneurysm
what is Darcy’s law
Q= (P1-P2)/R
what are autocoids
chemicals released from damaged tissue
histamine, bradykinin, 5ht, prostaglandins
name a vasodilator endothelial factor
BO
how does flow induced vasodilation occur
downstream vasodilation causes increased flow
this activates shear sensors in the endothelium and leads to vasodilation
which mechanism altering the radius of resistance vessels is under extrinsic control?
human alerting response
nerves - sympathetic vasoconstrictor action are dependant on firing
hormone – adrenaline
angiotensin II
which part of the aorta is the aortic root
runs between aortic valve and sinotubular junction
what branches off the aortic root
RCA LCA
which parts of the aorta are situated within the pericardial sac
the aortic root
the ascending aorta (up to 1cm pro to brachiocephalic trunk)
what is the significance of parts of the aorta being situated within the pericardial sac
risk of tamponade if dissection occurs
what are the major branches of the aortic arch
- the bracheocephalic trunk
- left common carotid
- left subclavian artery
major branches of descending thoracic aorta
- bronchial
- oesophageal
- intercostal
- spinal
- pericardial
define ischaemia
lack of blood supply from stenotic or occluded artery
this results in a lack of oxygen and essential metabolites
causes cell injury more rapidly than hypoxia
define infarction
irreversible cell damage due to ischaemia and hypoxia
