cardio Flashcards
Describe atherogenesis
- endothelial cells are damaged
- respond by secreting chemoattractant
- leukocytes migrate to intima
- a fatty streak is formed from foam cells, macrophages and T lymphocytes
- Foam cells rupture, releasing lipids
- smooth muscle cells migrate from media to the intima
- a dense fibrous cap with a necrotic core is formed
what causes ischaemia
A plaque partially occluding a lumen, restricting blood flow
What causes an infarction?
a plaque, which becomes unlodged, turning into a thrombus and fully blocking a vessel
Which arteries does atherogenesis occur most often in?
LAD, RCA and circumflex
What are the risk factors for ischaemic heart disease?
Family history
Age
Smoking
Hypertension
Diabetes
Obesity
High serum cholesterol
Bein Male
What is ischaemic heart disease?
Cardiac monocyte death due to insufficient oxygen-rich blood.
In ascending order of severity, describe IHD.
stable angina>unstable angina> non ST segment elevation myocardial infarction> STEMI
What can cause a NSTEMI or STEMI?
increased cardiac workload and occlusion of coronary arteries or insufficient oxygen-rich blood supply
Name 2 other causes of a STEMI or NSTEMI other than atherosclerosis.
Valvular(aortic stenosis) disease or anaemia
Describe stable angina.
Less than 5 minutes long of chest pain
brought on by exertion or exposure to cold
relieved by rest or GTN spray
Describe unstable angina/ NSTEMI/ STEMI.
Chest pain at rest that lasts longer than 20 mins
No relief from GTN spray
NSTEMI is where there is no ST segment elevation
STEMI is where there is ST segment elevation
What increases during an NSTEMI/ STEMI?
myoglobulin, troponin and CK levels
Describe Prinzmetsals angina.
Caused by coronary spasms, mainly at night or evening.
Describe the chest pain experienced in IHD.
Heavy, burning, squeezing, discomfort
Where does the pain of IHD radiate to?
The neck, shoulder, left arm and jaw.
What are some symptoms of IHD that would indicate that someone is not safe to work?
Nausea, sweating fatigue, weak breathing
Describe the atypical symptoms some patients may display with IHD.
Sweating
low grade fever
pale, cool clammy skin
hypo/hypertension
How is ischaemic heart disease diagnosed?
Through history taking and physical examination
Conducting a resting ECG or a exercise ECG to induce angina
Blood tests including cholesterol profiling, HBA1C, FBC,
A CT or coronary angiography
looking at biological markers such as Troponin, myoglobulin and CK
What is the most important inflammatory cytokine in plaques?
interleukin-1
What is aspirins method of action in platelet aggregation?
It inhibits COX-1(cyclooxygenase), which means that thromboxane A2 cannot form.
What effect does thrombin have on platelet activity?
A positive feedback effect
How does plasminogen utilise the thrombolytic system?
It skips a few steps, meaning that there is more plasmin to break down a fibrin mesh.
What effect does PY12 have on platelet activation?
It amplifies it
Name 3 PY12 antagonists.
Clopidogrel
Prasugrel
Tricagrelor
What does dual antiplatelet therapy refer to?
Aspirin with PY12 antagonist
clopidogrel
prasugrel
tricagrelor
What are the effects of GPIIb/IIIa inhibitors?
They prevent platelet aggregation
Name 3 GPIIb/IIIa inhibitors
Abciximab
Tirofiban
Eptifibatide
When are GPIIIb/IIa inhibitors used?
In combination with anticoagulant therapy for patients who have had STEMIs and are on opiates for pain, PY12 inhibitors are taken orally, so their effect is delayed due to delayed gastric emptying due to opiates.
Why must antiplatelets be used selectively?
They heighten the major risk of bleeding for the patient.
