Acute Coronary Syndrome, Angina Flashcards
What is the description of chest pain in patients with Angina?
Precipitated by exertional / emotional stress, and relieved by rest. May radiate to jaw, neck, left arm
What are the ECG changes visualised in patients with a STEMI or NSTEMI?
STEMI: ST elevation, Pathological Q wave
NSTEMI: ST depression, T-wave inversion
When does Troponin initially rise after an MI? How long does it remain high for?
Elevates 4-6 hours after injury, and remains elevated for up to 10 days
Why is CK-MB more useful for reinfarction than Troponin?
CK-MB levels deplete within 24 hours, whereas Troponin remains elevated for upto 10 days and would remain high in an infarct, masking it
In the early stages of an MI, why are cholesterol levels lowered?
High catecholamines are produced in the early phases, which lower cholesterol levels
What does the Left Anterior Descending (LAD) supply?
The right ventricle, left ventricle and intraventicular septum
From what order of arteries are the MI’s commonly occluded?
LAD (40-50%)
RCA (30-40%)
LCX (15-20%)
What does the Left Circumflex Artery (LCX) supply?
Supplies the lateral wall of the left ventricle
What does the Right Coronary Artery (RCA) supply?
Supplies the right atrium, right ventricle, the inferior wall / septum / papillary muscles of the LV
What three conditions make up Acute Coronary Syndrome?
NSTEMI, STEMI, Unstable Angina
Which layer of the arterial wall becomes a site for atherosclerosis?
Tunica intima
What ECG leads correspond to an MI in the LAD?
V1, V2, V3, V4
What ECG leads correspond to an MI in the LCX?
V5, V6, LI, aVL
What ECG leads correspond to an MI in the RCA?
LII, LIII, aVF
What might a posterior infarct look like on an ECG?
ST depression in the anterior leads
What is the difference between stable and unstable angina? How do each respond to GTN? What are the Troponin changes in each?
Stable angina - Exerted by stress, relieved by rest. Relieved by GTN. Troponin normal
Unstable angina - No particular time course. Relieved by GTN. Troponin normal
What is Levine’s sign?
Patient’s using a clenched first when describing their chest pain. Predictor for myocardial ischaemia
What are the three criteria to meet for Typical Angina? What if it meets less of the criteria?
- Substernal chest pain characteristic of angina
- Provoked by exertion / emotional stress
- Relieved by rest / GTN
If meets 2/3 -> Atypical angina
If meets 1/3 or 0/3 -> Non-cardiac chest pain
What is the description for NYHA Class 1 of Heart Failure?
No limitation of physical activity. Ordinary activity does not cause symptoms
What is the description for NYHA Class 2 of Heart Failure?
Slight limitation of physical activity. Comfortable at rest but ordinary activity results in symptoms
What is the description for NYHA Class 3 of Heart Failure?
Marked limitation of physical activity. Comfortable at rest but less than ordinary activity results in symptoms
What is the description for NYHA Class 4 of Heart Failure?
Severe limitation of physical activity. Discomfort at rest. Unable to perform any activities
In a CABG, what two structures can be typically harvested?
Long saphenous vein from legs or
Internal mammary arteries from thorax
What is Prinzmetal Angina?
Angina caused by vasospasm of the coronary arteries at rest
What is the ECG findings associated with Pericarditis?
Widespread concave ST elevation
PR depression
Which artery is likely to be affected in patients who have had an MI which had then lead to complete heart block?
Right coronary artery
What are the risk factors for Acute Coronary Syndrome?
Obesity, hypertension, smoking, family history, diabetes, male gender, hypercholesterolaemia, increasing age
What are the first-line, simple investigations for Acute Coronary Syndrome?
12-lead ECG Urea and electrolytes Full Blood Count Glucose Troponin Lipid profile CXR Echo Coronary angiography
What is the INITIAL management of a patient with Acute Coronary Syndrome?
MONA
Morphine, for severe pain, 5-10mg, repeat after 5 mins if necessary. Prescribe an anti-emetic alongside i.e. Metoclopramide 10mg IV or Cyclizine 50mg IV
Oxygen, only if < 94%
Nitrates, sublingually / IV. Caution if hypotensive
Aspirin, 300mg PO
What are some signs and symptoms of patients with Acute Coronary Syndrome?
- Central, left sided chest pain. May radiate to jaw, left arm. May feel heavy, constricting, “elephant on chest”
- Diabetics / elderly may not feel pain
- SOB, sweating, nausea, vomiting, clammy, pale
- Mildly altered observations
- Signs of cardiac failure
Why should beta-blockers and verapamil NOT be used concurrently?
Can precipitate asystole
How can an STEMI be diagnosed on ECG?
- Clinical symptoms of ACS, lasting at least 20mins
- Persistent ECG features in 2 leads of:
a. 2.5mm ST elevation in men <40 years in V2-V3
b. 2.0mm ST elevation in men >40 years in V2-V3
c. 1.5mm ST elevation in women in V2-V3
d. 1mm ST elevation in other leads - New LBBB
Outline the pathophysiology of Acute Coronary Syndrome
Caused by Ischaemic Heart Disease:
- Initial endothelial dysfunction, caused by smoking, HTN, hyperglycaemia
- Causes endothelial challenges which are pro-inflammatory, pro-oxidant, proliferative with reduced NO bioavailability
- Fatty infiltration of subendothelial space by LDLs
- Monocytes differentiate to macrophages, phagocytosing LDLs leading to foam cells
- Smooth muscle proliferation from tunica media to intima, causing formation of fibrous capsule
- Can lead to gradual narrowing and plaque rupture
State what the two methods of managing a STEMI is?
Percutaneous Coronary Intervention (PCI)
Thrombolysis
For STEMI management, using PCI
a. When should it be given?
b. What is the access?
c. What is given to patient before PCI?
d. What is given to patient during PCI?
a. Given if symptom duration is less than 12 hrs and can give PCI within 2 hours, or if symptoms are greater than 12 hours with evidence on ongoing ischaemia
b. Radial or femoral
c. Before PCI, give dual antiplatelet therapy (Aspirin + Clopidogrel (if on anticoagulant)
or Aspirin + Prasugrel (if not on anticoagulant)
d. During PCI, give UFH if radial access, or Bivalirudin if femoral access
For STEMI management, using Thrombolysis
a. When should it be given?
b. What are examples of Thrombolysis drugs?
c. What happens if it fails?
a. Within 12 hours of symptoms if PCI can’t be offered
b. Alteplase, Tenecteplase, Streptokinase
c. If ECG after 90mins of Thrombolysis show failure, offer PCI
What are contraindications for Thrombolysis in managing STEMI patients?
- Active internal bleeding
- Recent haemorrhage, trauma, surgery
- Coagulation and bleeding disorders
- Intracranial neoplasm
- Stroke <3 months ago
- Aortic dissection
- Recent head injury
- Severe HTN
Following MONA, what is the management of an NSTEMI?
- Aspirin 300mg PO, followed by 75mg PO
- Clopidogrel 300mg PO, followed by 75mg PO (Ticagrelor is an alternative)
- Anticoagulation, Fondaparinux 2.5mg PO OD (LMWH is an alternative)
- Beta blockers
- Nitrates
- ACEI
- Atorvastatin
- What is the mechanism of the action of statins?
- What are the adverse events?
- Myalgia is associated with what statins in particular?
- What baseline tests would you do for statins in particular?
- When would you discontinue statins with respect to LFTs?
- Who should have a statin?
- What are contraindications to statins?
- How should statins be taken?
- HMG-CoA reductase Inhibitor, controls the rate-limiting step of hepatic cholesterol synthesis
- Myopathy, liver impairment, increased stroke risk in patients with previous stroke
- Lipophillic statins, i.e. Simvastatin, Atorvastatin
- LFTs at baseline, 3 months and 12 months
- If AST is 3x the ULN, then discontinue
- All patients with established CVD, or if QRISK greater than 10%
- Pregnancy, if on current macrolides (clarithromycin, erythromycin)
- At night
What is the management of a patient with stable angina?
RAMP
R - Refer to cardiology
A - Advice them about diagnosis, management, when to call 999
M - Medical management
a. Immediate management -> GTN
b. Long term management -> BB or CCB
c. Secondary management -> Aspirin, ACEI, Atorvastatin
P - Procedural management
a. PCI w/ Coronary Angioplasty
b. CABG
What scars may you want to look for in a patient with angina / ACS?
PCI scars: Femoral / radial / brachial scars
CABG scars: Midline sternotomy, long saphenous vein / internal mammary artery harvesting