Acute coronary syndromes Flashcards
What occurs in stable angina?
Fixed stenosis of the coronary arteries results in demand (due to exertion) led ischaemia, causing central chest pain
What are the 3 S’s of stable angina treatment?
Stop
Sit
Spray GTN
What are the 3 diseases that fall under the term ‘acute coronary syndrome’?
STEMI
NSTEMI
Unstable angina
What is meant by STEMI?
ST Elevation Myocardial Infarction
What is meant by NSTEMI?
Non ST Elevation Myocardial Infarction
What occurs in both a type I STEMI and NSTEMI?
Build up and rupture of an atherosclerotic plaque leads to occlusion of a coronary artery
What are some characteristics of vessels and plaques that make them more prone to rupturing?
Thickness of fibrous cap
Lipid content
Changes to intraluminal pressure
Bending and twisting of an artery
Plaque shape
Mechanical injury
What would occlusion of one of the left coronary artery branches lead to?
Left side fibrosis, leading to left sided heart failure
What are some symptoms of left sided heart failure?
Paroxysmal Nocturnal Dyspnoea
Cough
Orthopnoea
Exertional dyspnoea
Cyanosis
Blood tinged sputum
Elevated pulmonary capillary wedge pressure
What are some symptoms of STEMI?
History of severe, central, crushing chest pain that radiates to the jaw and arms (especially left)
Prolonged and not relieved by GTN spray
Can cause sweating, nausea and vomiting
What are some characteristics of a STEMI on ECG?
≥1mm ST elevation in 2 adjacent limb leads OR ≥2mm ST elevation in ay least 2 contiguous (Next to each other) precordial (Chest) leads
T wave inversion
Q waves
Left bundle branch block
How does the ECG of a person having a STEMI change over time?
First few hours = ST elevation
First day = Large Q wave formation
Long term = Inverted T waves may form
What ECG leads are inferior?
Lead II, III and aVF
Which ECG leads are anteroseptal?
V1-V2
Which ECG leads are anterior?
V3-V4
Which ECG leads are anterolateral?
V5-V6
Which ECG leads are lateral?
I, aVL and aVR
What can be seen on ECG in a left bundle branch block?
Broad QRS complexes >120ms with an inter-ventricular conduction delay, leading to a notched QRS which is very positive in the lateral leads
What diagnostic test is used along side ECG to detect an MI?
Troponin
What is the troponin test and what do the results show?
The troponin test tests for the presence of troponin I and troponin T, which are cardiac specific and are used to detect cardiac myocyte damage. A result greater than the 99th percentile is used to diagnose an MI
What is the treatment option for a person with a STEMI, who is >120 minutes away from a PCI laboratory?
IV Diamorphine - analgesic
IV anti-emetic
GTN spray if BP >90mmHg systolic
Oxygen if hypoxic
300mg aspirin (Chewed) + either:
180mg ticagrelor
60mg prasugrel
300mg clopidogrel
Possible Fondaparinux/LMW heparin
ß-Blocker
Then prehospital thrombolysis using tPA
Then PCI or monitoring at nearest PCI lab +/- GPIIbIIIa inhibitor
What is the treatment option for a person with a STEMI, who is <120 minutes away from a PCI laboratory?
IV Diamorphine - analgesic
IV anti-emetic
GTN spray if BP >90mmHg systolic
Oxygen if hypoxic
300mg aspirin (Chewed) + either:
180mg ticagrelor
60mg prasugrel
300mg clopidogrel
Possible Fondaparinux/LMW Heparin
ß-Blocker
Then PCI (Percutaneous Coronary Intervention) +/- GPIIbIIIa inhibitor
What are some arrhythmic complications of acute MI?
Ventricular fibrillation can occur which causes highly chaotic muscular contraction, leading to stasis. This can be treated using defibrillation (Direct Current Cardioversion)
What are some structural complications that can arise due to acute MI?
Cardiac rupture
Ventricular septal defect
Mitral valve regurgitation
Left ventricular aneurysm formation
Mural thrombus +/- systemic emboli
Inflammation
Acute pericarditis
Dressler’s syndrome
