Heart Attack Flashcards
What are the characteristics of stable angina?
- fixed stenosis
- demand led ischaemia
- predictable
- safe
What advice is given to patients having an angina attack?
‘stop, sit spray’ - have one spray of GTN leave 5 mins and spray again - if pain persists call 999
Define acute coronary syndrome
any acute presentation of coronary disease
- unstable angina
- acute non-STEMI
- STEMI
How does it differ from stable angina?
- dynamic stenosis
- supply led ischaemia
- unpredictable
- dangerous
Name six factors affecting plaque rupture
- lipid content of plaque
- thickness of fibrous cap
- sudden changes in pressure
- bending/twisting of artery
- plaque shape
- mechanical injury
What is the result of an occlusion in a stemi?
everything downstream from the occlusion starts to die
Can heart muscle regenerate?
Nope - it begins to scar
What is the result of scarring?
Dilation & aneurysm –> heart failure
Describe a classical presentation of a heart attack
Severe, central crushing chest pain radiating to the jaw and left arm. Associated with sweating and nausea
What must be present to diagnose a STEMI from an ECG?
> 1mm ST elevation in 2 adjacent limb leads
>2mm ST elevation in 2 contiguous precordial leads
What other changes may be seen on an ECG?
Q wave formation, T wave inversion
Other than ECG what other test can be done on a patient with a suspected MI?
Protein markers & enzymes
Troponin & Creatinine Kinase
What are the three types of troponin?
Troponin C - binds to calcium
Troponin I - binds to actin (deactivates actin after contraction)
Troponin T - facilitates contraction by binding to tropomyosin complex
In ischaemia what happens to troponin levels?
They rise 2-4 hours after an MI
What does elevated troponin signify?
Cardial necrosis
What is the early treatment for a suspected MI?
Morphine ( and anti-emetic) Oxygen Nitrates Aspirin 300mg (chewable) \+Clopidogrel 300mg
When is thrombolysis administered?
If it is going to take more than 2 hours to get the patient to the cath lab for PCI
What is an alternative to clopidogrel?
Ticegralor 180mg
Name an anti-emetic
Metaclopramide
Name four types of complications of an MI
- Death
- Arrhythmic complications
- Structural complications
- Functional complications
What is the main, life threatening arrhythmic complication?
Ventricular fibrillation
Name three structural complications
- cardiac rupture (left ventricle)
- ventricular septal defect
- mitral valve regurgitation
Name three functional complications
- acute ventricular failure
- chronic cardiac failure
- cardiogenic shock
What are the four classes of the killip classification?
Risk of mortality I - no signs of HF 6% II - creps <50% 17% III - creps >50% 38% IV - cariogenic shock 81%
