Cardiology Flashcards
Break down the word atherosclerosis
Atheroma= fatty deposits in artery walls Sclerosis= process of hardening or stiffening of blood vessels
What is atherosclerosis caused by?
Chronic inflammation and activation of the immune system in the artery wall which causes deposition of lipids
What three things do fibrous atheromous plaques lead to?
- Stiffening - leads to hypertension and strain of heart pumping against resistance 2. Stenosis - leads to reduce blood flow (eg. Angina) 3. Plaque rupture- giving off a thrombus that blocks a distal vessel leading to ischaemia (eg. Acute conorary syndrome)
Atherosclerosis non-modifiable risk factors
- Older age 2. Family history 3. Male
Atherosclerosis modifiable risk factors
- Smoking 2. Alcohol consumption 3. Poor diet (High sugar and trans-fat and reduced fruit and vegetable and omega 3 consumption) 4. Low exercise 5. Obesity 6. Poor sleep 7. Stress
Medical co-morbidities that increase the risk of atherosclerosis
- Diabetes 2. Hypertension 3. Chronic kidney disease 4. Inflammatory conditions (rheumatoid arthritis) 5. Atypical antipsychotic medications
End result of atherosclerosis?
- Angina 2. Myocardial infarction 3. Transient ischaemic attacks 4. Stroke 5. Peripheral vascular disease 6. Messenteric ischaemia
Two types of prevention of cardiovascular disease?
- Primary prevention - for patients that have never had cardiovascular disease in the past 2. Secondary prevention - for patient that have had angina, myocardial infarction, TIA, stroke or peripheral vascular disease
How to optimise modifiable risk factors?
- Advice on diet, exercise and weight loss 2. Stop smoking 3. Stop drinking alcohol 4. Tightly treat co-morbities (diabetes)
Primary prevention of cardiovascular disease?
- Perform a Q-risk 3 score 2. Over 10% risk of having heart attack or stroke in the next ten years? Offer a statin (Current NICE = atorvastatin 20mg at night) 3. All patients with CKD or type 1 diabetes for more than ten years should also be offered atorvastatin 20mg
Nice guidelines to statin prescription?
- check lipids at 3 months- aim for increasing dose to aim for 40% reduction in non-HDL Cholesterol- always check adherence first! 2. Check LFTs within 3 months and at 12 months, don’t need to be checked again if normal 3. Statins can cause a transient and mild raise in ALT and AST in first few weeks of use and don’t need stopping if rise is less than 3 times the upper limit of normal
Secondary prevention of cardiovascular disease?
4 As: Aspirin (plus second anti platelet like clopidogrel for 12months) Atorvastatin 80mg Atenolol (or other beta-blocked - commonly bispropol - titrated to maximum tolerated dose) ACE inhibitor (commonly ramipril) (tritated to max tolerated dose)
Notable side effects of statins
- Myopathy (check creative kinase in patients with muscle pain or weakness) 2. T2DM 3. Haemorrhagic strokes (very rarely) Usually benefits far outweigh risks and newer statins are mostly very wel tolerated
What’s a Q-risk 3 score?
-Predicts risk of CVD in 10 upcoming years -Factors include: Age SBP BMI Socieconomic status Ethnicity -Score of ten plus (10% + risk in the next ten years) is an indication to start 1° lipid lowering therapy (statins)
What is atorvastatin an example of?
Lipid lowering therapy
Which arteries does atherogenesis affect most commonly?
LAD Circumflex RCA
Risk factors for IHD
Age Smoking Obesity, high serum cholesterol Diabetes Hypertension Family history M>F Cocaine use Stress Physical inactivity
Symptoms of stable angina pain?
- Central crushing chest pain radiating to neck/jaw 2. Brought on with exertion 3. Relieved with 5mins rest or GTN spray
Four types of angina?
- Stable - normal three point definition 2. Unstable - pain at rest, not relieved by inactivity or GTN spray + no ECG CHANGES 3. Prinzmetal’s - due to coronary vasospasm (not due to cv vessel atherogenesis) Seen increasingly in cocaine users ECG shows ST elevation 4. Decubitus - induced when lying flat (usually complication of cardiac failure)
Patholophysiology of ischaemic heart disease?
Atherogenesis: Endothelial injury attracts cells to site via chemokines (IL1, IL6, IFN-Y) 1. Fatty streak = Foam cells (lipid laden macrophages) and T-cells 2. Intermediate lesions = foam cells (bigger as taken up more lipid), t- cells and smooth muscle cells Platelets also aggregate and adhere to site inside vessel lumen 3. Fibrous plaques (advanced) = large lesions (foam cells, t-cells, smooth muscle, fibroblasts, lipids with a necrotic core) Develops a fibrous cap over lesion
Fibrous cap in stable angina?
Fibrous cap is strong and less rupture prone
What happens if plaque is prone to rupture?
Prothrombotic state, platelet adhesion and accumulation leads to progressive luminal narrowing
Difference between ischaemia and infarction?
Ischaemia= blood flow restricted Infarction= lumen fully occluded
When do symptoms for stable angina start?
When 70 to 80% lumen occluded Due to poiseulle’s law, nothing much happens until the diameter stenosis reaches 70% and then there is rapid decline