What is the difference between: • Arteriosclerosis • Atherosclerosis • Atheroma
Answer: • Arteriosclerosis: A group of diseases related by hardening arteries, of which atherosclerosis is one. • Atherosclerosis: A disease involving hardening, narrowing and weakening of the arterial wall, characterised by the presence of atheromas. • Atheroma: A chronic lesion in the intima tunica of the artery, characterised by the pathological build-up of lipids, inflammatory cells and smooth muscle.
Histopathological Changes • Injury to the endothelium allows LDL into the intima, this LDL starts to oxidize. • Macrophage invade the intima and ingest the oxidized LDL, becoming pathological foam cells because they can not break it down. • Foam cells recruit other white blood cells and activate a generalised immune response, causing inflammation. • Foam cells release growth factors which cause smooth muscle infiltration from the media into the intima, further narrowing the artery. • Smooth muscle can begin to calcify and become brittle, leading to rupture and embologenesis.
1) Fatty Streaks • Irregular patches • Matter is beneath intima (fibrous cap) • Mostly foam cells at this point • Smooth muscle cell infiltration has also begun
2) Fibrofatty Plaque • Atheroma now much more widespread • Lots of smooth muscle infiltration • Filled with lots of other stuff like fibrin, collagen and bits of cells. • Calcification may have begun.
3) Complicated/Advanced Plaque Presence of one or more of: • Cracking of fibrous cap • Bleeding into the atheroma • Superimposed thrombus • Very large fibrous cap
Complications of Atherosclerosis - CHEAT • Critical Stenosis – e.g. Peripheral Vascular Disease • Haemorrhage – i.e. Burst Vessel • Embolism • Aneurysm –Can then develop into lots of problems • Thrombosis in situ
Diagnosis • Usually secondary to whatever the complication is. • Angiography is the gold standard. • High cholesterol does not necessarily mean atherosclerosis, but there is a strong link. • Look for signs and history to screen for hyperlipidaemia. • Patient history of hypertension, family history of familial hypercholesterolaemia, social history of poor diet and smoking. • Xanthelasma – well-defined lumps of fat around eyes.
Treatments • Stop health-damaging behaviours – smoking, fatty diet, low exercise • Treat hypertension and hyperlipidaemia • Stenting (Percutaneous) • Coronary Artery Bypass Graft (CABG)