Acute cardiovascular disease Flashcards
pathology, management, dental implications of ACS and PAD
what three diseases does acute coronary syndrome entail? how are these caused?
- stable angina
- STEMI - ST-elevation MI
- NSTEMI - non-ST-elevation MI
caused by supply and demand mis-match of oxygen to the myocardium causing blockage of blood flow or increased demand
what is a STEMI?
total occlusion of coronary artery
infarction
what is unstable angina?
partial occlusion of coronary artery
ischaemia - reduced amount of blood flow to heart
no infacrction
what is a NSTEMI?
partial occlusion of coronary artery
ischaemia - reduced amount of blood flow to heart
infarction
how does ischaemia occur in the coronary arteries and what can it lead to?
5
- atherosclerosis plaque causes narrowing of vessels
- small proportion of plaque can break off and travel in the blood stream (embolise)
- becomes lodged and causes blockage of blood flow to tissue (thrombus)
- reduced blood flow results in ischaemia
- can lead to infarction and necrosis of tissue
what are the symptoms of acute coronary syndrome?
10
- central, crushing chest pain
- pain radiating to left arm or jaw
- nausea and vomiting
- sweating and clamminess
- feeling of impending doom
- shortness of breath
- palpitations
- dizziness
- grey
- cool peripheries
what are the complications of ACS?
5
death (cardiac arrest)
arrythmia
heart failure
rupture of heart wall
new valvular disease (papillary muscle infarction)
how do you diagnose ACS?
2
ECG - electrocardiogram
blood test for troponin - protein in eart muscle released when heart infarcts
describe briefly the three steps of managing ACS
immediate management
* minimise tissue loss from infarction
re-establish blood flow
* break up, remove and dissolve clot in hospital procedure
prevent further episode
* lifestyle management and medication
what occurs in the immediate management of ACS in the dental practice?
5
- acute onset chest pain = do not know if it is stable/unstable angina, STEMI or NSTEMI
- phone ambulance, get to hospital
- 100% oxygen via non-rebreather mask
- GTN 2 sprays sublingual, repeat after 3 mins if no improvement
- 300mg aspirin tablet chewed
what three medications given for the acute management fo ACS and what do they do?
- oxygen - limits infarct size as more O2 to ischaemic myocardium
- GTN spray - vasodilator, releases NO in vascular smooth muscle to reduce preload on heart (vena cava) and increases blood flow through coronary arteries
- 300mg aspirin - prevents thrombus enlarging and reduces platelet aggregation at clot by inhibiting COX enzyme
what happens during reperfusion at the hospital?
2
- break up and remove blood clot
* percutaneous coronary intervention (PCI), access from femoral artery
* break up clot
* widen artery (angioplasty) and place stent to maintain width
* within 120 mins of onset - dissolve blood clot
* thrombolysis - clot-busting drug (alteplase)
what are the secondary prevention methods for ACS?
2
- lifestyle measures - hypertension, obesity, lipids, diabetes, smoking, alcohol
- medications - 5As
- Aspirin 75mg
- Another antiplatelet (e.g. clopidogrel for 12 months)
- Atorvastatin (lipid lowering)
- ACE inhibitor (blood pressure)
- Atenolol (or another beta blocker - bisoprolol)
what are the dental implications for patients with ACS?
managing medical emergency - dentist is stress-inducing for patients
shared risk factor with periodontal disease - smoking
antiplatelet medication - bleeding risk
use of LA with adrenaline - risk of cardiac arrythmia or inducing ACS
when should you avoid giving LA with adrenaline?
2
recent MI <6 months
severe hypertension or unstable arrythmia
