Cardiovascular Flashcards
What is angina?
Pain in chest, arms and throat, brought on by exertion and relieved by rest. Physiology of demand exceeds blood supply
Why is smoking bad for angina patients?
Damages endothelium, affects peripheral blood flow and perfusion due to vasoconstriction. Also aids platelet aggregation.
Why is alcohol bad in cardiac patients?
Raised TGs in blood and blood pressure
How does atherosclerosis lead to coronary thrombosis?
Partial occlusion, macrophages produce protease and smooth muscle undergoes metaplasia to form fibrous cap, lipid core ruptures, changed in flow and platelet aggregation due to rough endothelium and tissue factor
What is collateral circulation?
When blood vessels grow to supply an ischaemic area of tissue. Ischaemic tissue releases mediators so endothelium proliferates and can open up and enlarge (in time)
Why could ischaemia cause atrial fibrillations
Na/K pumps need ATP, less ATP means depolaristion of myocardium might not happen so impulses can’t spread = fibrillations
Explain how rupture of the heart wall might occur after myocardial infarction
Iscahemic tissue leads to inflammation and neutrophils migrate and release enzymes. Collagen and elastin are broken down, macrophages also produce enzymes, infarct is digested. Huge pressure, weak wall ruptures into pericardium
What happens when the heart wall ruptures?
Blood ruptures into pericardium, R atrium collapses under increased outside pressure, no venous return, raised JVP
What are the risks for thrombosis?
Elderly, hypertension, high LDL cholesterol, diabetes, smoking
Infection, lack of exercise, obesity?, stress, genes
What could cause endothelial injury?
Raised LDL, toxins, hypertension, haemodynamic stress
What is fibrin?
Insoluble fibrillar protein that forms a meshwork for a haemostatic plug
