Chapter 4: Cardiac Causes of Cardiac Arrest Flashcards
How can acute coronary syndrome be split up?
ST elevated myocardial infarction
Non ST Elevated acute coronary syndromes:
- NSTEMI
- Unstable angina
What can be used to determine between STEMI and NSTEMI?
ST elevation or new LBBB = STEMI
Other ECG changes = NSTEMI/Unstable angina
How do you differentiate between unstable angina and NSTEMI?
Troponin release
What may indicate that a non-ST elevated ACS may be high risk?
ST depression Dynamic ECG changes (different from baseline) Unstable rhythm Unstable haemodynamics Diabetes High GRACE score
Which groups of people may present with ACS less typically?
Females
Elderly
Diabetics
What are some atypical symptoms of ACS?
Indigestion type pain
Pain radiate to throat, into one or both arms, into back or upper abdomen
Asymptomatic
What ECG changes can an NSTEMI/unstable angina show?
Normal
ST Depression
Non specific abnormalities - t wave inversion
When is risk of progression from NSTEMI to full occlusion highest?
First few hours, days and months
What is there a substantial risk of in the acute phase of a STEMI?
VF
VT
Sudden death
What ECG changes may be seen in a STEMI?
ST elevation
New LBBB
Pathological q waves
T wave inversion
Hyperacute t waves (v early)
How quickly do you aim to give PCI in a STEMI? What should you do if this can not be achieved?
Within 120 minutes of onset of chest pain
Fibrinolytic therapy
Which leads indicate where an infarct may be?
Anterior - V1-4 = LAD
Inferior - II, III, AVF = RCA
Lateral - I, AVL, V5-6 = Left Circumflex
Posterior - Reciprocal changes to anterior (ST Depression in V1-4 and dominant R wave in V1 AND V2)= RCA
What is important to know about posterior MI’s?
Must confirm with posterior leads
Risk of bradycardia as sinoatrial node may be affected
What other conditions can cause ST elevation or depression, not related to the heart?
Subarachnoid haemorrhage
Traumatic brain injury
Why are ECHOs useful in acute ACS?
Confirm LV systolic function - related to prognosis
Can prompt diagnoses of cardiomyopathy, valve disease, pericardial disease, aortic dissection and PE
Can confirm RV dilatation and impairment
What are the GRACE and CRUSADE scores?
GRACE - predict risk of adverse outcome
CRUSADE - Risk of major bleeding during hospital admission following ACS
Within what time frame should reperfusion be post STEMI without delay?
If presenting within 12 hours - PCI or fibrinolysis
What anti-thrombotic therapy should patients having a PCI be given and what dose?
Aspirin 300mg + 1 of
- Clopidogrel 600mg
- Prasugrel 60mg (not if >75, <60kg or hx of bleeding/stroke)
- Ticagrelor - 180mg
Anticoag with heparin is given in Cath lab - Bivalirudin is alternative
In high-risk, glycoprotein IIb/IIIa inhibitor may be given
Also give GTN and morphine PRN, may need anti-emetics too.
What are the typical indications for fibrinolytic therapy?
1 of:
- STEMI >0.2mV in 2 adjacent chest leads or >0.1mV in 2 adjacent limb leads
- Dominant R waves and ST depression in V1-3 (post MI)
- New onset LBBB
What is given alongside fibrinolytic therapy for STEMI?
Also the treatment for NSTEMI/ACS
- Aspirin 300mg loading dose AND
- Clopidogrel 300mg loading dose/ticagrelor 180mg loading dose AND
- Antithrombin therapy: LMWH, unfractionated heparin or fondaparinux