macrovascular complciations Flashcards
DIAGRAM progession of atherosclerosis to form atheroma
initial lesion due to macrophage accumulation and foam cell production- fatty streaks then form due to INTRACELLULAR LIPID accumulation- lipid then spills out to form a core of extracellular lipid (atheroma), which surrounded by fibrotic layer (through collagen and VCSM- thrombosis may then occur on lesion
factors increasing risk of CVD
fasting glucose above 6mmol low HDL/LDL (different for women to men) hypertension waist circumference IR/inflammation (via adipocytokines) and urine microalbumin lead to increased risk as well
how factors affect different stages of atherosclerosis
IR, lipids and BP can lead production of extracellular lipids IR alone then leads to progression of atheroma and thrombosis
danger of hyperglycaemia and diabetes
associated with much lower life expectancy- the longer someone has diabetes, the more damage it causes ie someone diagnosed earlier will die earlier
diabetes in men vs women
increased risk of death in men, BUT increased risk of CVD in women
risk of macro vs microvascular complciations with increased blood sugar
the higher your blood sugar, there is MUCH greater increase in retinopathy, but a SMALLER risk for infarction
difference between microvascular and macrovascular disease in terms of danger
micro causes morbidity ONLY, macro causes that AND mortality
post-MI survival in diabetics vs non diabetics
post-MI survival much lower in diabetics
effect of ethnicity on CVD
south asians tend to be at greatest risk
key concept of macrovascular disease
SYSTEMIC ie affects mutiple arterial beds, so different organs- eg in CEREBROVASCULAR DISEASE, likely to be multiple small infarcts in brain. in PERIPHERAL VASCULAR DISEASE, blockage of arteries (atheroma) supplying legs can affect multiple beds, leading to foot disease for example. finally, atheroma in artery supplying kidney causes RENAL ARTERY STENOSIS, which can lead to hypertension and renal failure
effect of glucose lowering on CVD
has minor effect, mortality is not lowered, thus lipids and BP more important
risk factors for macrovascular disease and thus clinical important
non-modifiable are age, sex, birth weight (lower weights more at risk) and certain genes. modifiable are dyslipidaemia (LDL/HDL), BP, smoking and diabetes (ie sugar)- thus aggressive treatment of all these is important eg statins
canakinumab
reduces inflammation without lowering lipid levels- lowers risk of CVD, but problem is it increases risk of infection
predisposing risk factors to DIABETIC FOOT DISEASE
although peripheral vascular disease (blockage) important, neuropathy (sensory, motor AND autonomic) more important
epi of diabetic foot disdease- prevalence, amputation and beds
5% of diabetics have it- increases risk of amputation by 60*- 10% of NHS beds taken by diabetes, half of which due to foot disease
pathway to foot ulcerations (breakage of skin)
sensory neuropathy (using monofilament as test) motor neuropathy- cannot balance weight on foot, so lotsof pressure on certain part of foot (shape of foot also lost) limited joint mobility- sugar sticks to collagen, preventing walking autonomic neuropathy- integrity of skin lost due to glands being affected= dry and weak peripheral vascular disease adds to problems- trauma, increased risk of infection (microbes love sugar) and other diabetic complications like retinopathy can help lead to ulceration
types of foot ulcerations DIAGRAM
neuropathic foot- numb, warm (getting blood) but dry, foot pulses present, and ulcers at points where high pressure is (often at big toe) ischaemic foot- cold, no pulse, ulcers at foot extremities (where no blood going) both- combining the two
how to assess foot of diabetic patient
appearance- is it deformed/calluses how does foot feel- hot/cold and or dry look at presence/absence of foot pulses look at neuropathy through fine touch
managing diabetic foot disease
control diaebetes inspect feet daily- measure feet when buying shoes, and buy shoes with laces don’t cut nails too short (may causes ulcer), caution with heat, and don’t walk barefoot
managing foot ulceration
relieve pressure through bed rest antibiotics revascularisation (angioplasty) debridement (getting rid off dead tissue as potential for infection) or complete amputation
charcot foot DIAGRAM
where foot deformed so that most of weight through middle of foot- this would cause pain, but diabetics are neuropathic, so can’t feel it, thus constant walking causes ulceration
