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Flashcards in Acute coronary syndrome Deck (40)
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Most common clinical presentation of angina

Chest pain on exertion


Key factors contributing to progression of atheroma



Associated symptoms with angina



Atheroma formation

1. Damage to the arterial wall produces an inflammatory response and the development of atheromatous plaques.
2. Exposure of the arterial endothelium to LDLs, the products of glycosylation associated with diabetes, vasoconstrictor hormones associated with hypertension, pro-inflammatory molecules from smoking, or excess adipose tissue results in the expression of adhesion molecules that allow leukocytes to stick to the arterial wall.
3. Upon entry into the artery wall, blood monocytes begin to scavenge lipids and become foam cells.
4. Macrophage foam cells release additional cytokines and effector molecules that stimulate smooth muscle cell migration from the arterial intima into the media, as well as smooth muscle cell proliferation.
5. Initial fatty deposition of lipoprotein in the arterial intima develops into atherosclerotic plaques.
6. Ischaemic symptoms may result from obstruction of blood flow due to atherosclerotic plaques or when a clot or vasospasm is superimposed on less severe plaques


At what occlusion % does angina typically occur

At >70% occlusion or coronary arteries


Precipitants of angina with fixed stenosis

mental and emotional stress, sexual activity, tachycardia from any cause, or the metabolic demands of fever, thyrotoxicosis, and hypoglycaemia


Types of angina

Stable: induced by activity, relieved by rest
Unstable: +frequency or severity, occurs on minimal exertion/at rest. ++Risk of MI
Prinzmetal: coronary artery spasm->at rest, STE that resolves once pain resolves


Risk factors for angina


advancing age
elevated LDL cholesterol
isolated low HDL cholesterol
family history of premature ischaemic heart disease
illicit drug use
male sex


Investigations in angina

Resting ECG->normal
Fasting lipid profile
Fasting blood glucose

Others to consider:
TSH->hypo(dyslipid, IHD)/hyper(+work load)
Stress ECG
Stress echocardiograph


History and examination in angina

Angina pain syndrome description
Risk factors
Examination: associated cardiac, PAD, fundoscopy, bruits
Laboratory testing


Long term Management of stable angina

1. Modify risk factors->beta blocker, statin, Anti-PLT, ACE-i
2. Lifestyle->smoking cessation, exercise, diet
3. Cardiac rehabilitation
4. Consideration of revascularisation
5. Management of acute symptoms
6. Avoid precipitants


Pharmacological regime for angina risk modification

Aspirin 75-150mg OD
Metoprolol 25-100mg BD +/= Nifedipine (used if not controlled with b-blocker/verapamil) + Isosorbide mononitrate
Atorvastatin 80mg


Treatment of episodes of angina

Stop activity as soon as pain felt
Before taking medication lay down'GTN SL every 5 minutes. Max use 3 times
If persists >10minutes despite two doses, take a third and call the ambulance


Follow-up in angina

Assess risk factors, symptoms, complications, promote adherence to lifestyle/pharmacological
See every 4-6 months initially to help encourage smoking, weight, diet, activity
Patients not known to have diabetes mellitus should have a fasting blood glucose measurement every 3 years
Those with established diabetes mellitus should have HbA1c measured at least annually
A lipid profile should be obtained as clinically warranted to ascertain whether the goal of lowering LDL cholesterol by ≥50% is achieved and/or to check for compliance.


What is the single most important change people can make for cardiovascular health

Smoking cessation


Indications for referral in angina

Diagnostic uncertainty
New angina of sudden onset
Angina not controlled by drugs
Refractory angina in those not suitable for CAG
Previous CABG
Positive stress test


Definition ACS

Unstable angina


Diagnosis of MI`

+ then -ve cardiac biomarkers +symptoms of ichemia or ECG changes of new ischemia or development of Q waves or loss of myocardium on imaging


Symptoms of ACS

Chest pain >20 mins
Sweaty, Nausea, dyspnea, palpitations


Signs of ACS

Distress, anxiety, pallor
TachyC, bradyC
4th heart sound
Evidence of heart failure
Pansystolic murmur of papillary muscle, VSD
Friction rub


Investigations in ACS

Cardiac enzymes
Coronary angiogram

Consider echo


Management of STEMI

1. Do a 12 lead ECG->confirmed
2. 02 2-4 L->aim for saturations >95%
3. IV access->bloods for GBC, UECm glucose, lipids, cardiac enzymes
4. Brief assessment:
-CVD history and risks
-Contraindications to fibrinolysis
-Examination; pulse, BP (both arms), JVP, murmurs, HF, limb pulses, scars from previous surgery
5. Aspirin 300mg chewed
6. Clopidogrel 300mg (if followed by lysis) 600mg (if followed by PCI)
7. Morphine 5-10mg IV + metoclopramide 10mg IV
8. GTN SL 2 puffs/1 tables
9. Primary PCI (need heparin) or thrombolysis
10. Metoprolol + statin + ACEi
11. CXR
12. DVT prophylaxis
13. Wean off GTN when stabilised
14. Stop heparin when pain free for 24 hours (give at least 3-5 days)
15. Serial ECGs, troponins >12 h after pain
16. Address modifiable risk factors
17. Gentle mobilisation
18. Notify/arrange f/u with GP


Ways to restore blood flow



When should PCI be performed within

performed within:

60 minutes for patients presenting within the first hour of symptom onset
90 minutes for patients presenting between 1 and 3 hours after symptom onset
90 to 120 minutes for patients presenting between 3 and 12 hours.


If targets for PCI cannot be achieved in STEMI

Fibrinolysis given within 30 mins of arriving at hospital


Consideration for reperfusion therapy

Patients should be considered for reperfusion therapy only if all of the following are present:

1. Ischaemic/infarction symptoms of longer than 20 minutes. This would include not only chest pain but also other symptoms of myocardial infarction such as chest discomfort or pressure, shortness of breath, pulmonary oedema, sweating, dizziness and light-headedness
symptoms commenced within 12 hours
2. ST elevation or presumed new left bundle branch block on ECG
3. No contraindications to reperfusion therapy.


Indications for fibrinolysis

prolonged ischaemic chest pain that has begun within the previous 12 hours, in the presence of significant ST segment elevation or left bundle branch block that is presumed new


Absolute contraindications for thrombolysis

Risk of bleeding
-active bleeding or bleeding diathesis (excluding menses)
-significant closed head or facial trauma within 3 months
-suspected aortic dissection (including new neurological symptoms)

Risk of intracranial haemorrhage
-any prior intracranial haemorrhage
-ischaemic stroke within 3 months
-known structural cerebral vascular lesion (eg --arteriovenous malformation)
-known malignant intracranial neoplasm (primary or metastatic)


Relative contraindications for thrombolysis

Risk of bleeding
-current use of anticoagulants: the higher the international normalised ratio (INR), the higher the risk of bleeding
non-compressible vascular punctures
-recent major surgery (within 3 weeks)
-traumatic or prolonged (more than 10 minutes) cardiopulmonary resuscitation
-recent (within 4 weeks) internal bleeding (eg gastrointestinal or urinary tract haemorrhage)
active peptic ulcer

Risk of intracranial haemorrhage
-history of chronic, severe, poorly controlled hypertension
severe uncontrolled hypertension on presentation (more than 180 mm Hg systolic or more than 110 mm Hg diastolic)
-ischaemic stroke more than 3 months ago, dementia, or known intracranial abnormality not covered in absolute contraindications



Fibrinolysis regime

Alteplase + heparin


When should long term anticoagulation therapy be considered following MI

When large
Akinetic/dyskinetic area
Left mural thrombus on echo

Enoxaparin + warfarin


ECG criteria for thrombolysis

STE >1mm in 2 + limb leads or >2mm in 2 or more chest leads
LBBB of new origin
Posterior changes


High risk features in NSTEMI

Presentation with clinical features consistent with acute coronary syndrome (ACS) and any of the following high-risk features:
1. repetitive or prolonged (more than 10 minutes) ongoing chest pain or discomfort
2. elevated level of at least one cardiac biomarker (troponin or creatine kinase-MB isoenzyme)
3. persistent or dynamic electrocardiographic changes of ST-segment depression 0.5 mm or more, or new T-wave inversion 2 mm or more
4. transient ST-segment elevation (0.5 mm or more) in more than two contiguous leads
5. haemodynamic compromise—systolic blood pressure less than 90 mm Hg, cool peripheries, diaphoresis, heart failure, and/or new-onset mitral regurgitation
6. sustained ventricular tachycardia
7. syncope
8. left ventricular systolic dysfunction (left ventricular ejection fraction less than 0.40)
9. prior percutaneous coronary intervention within 6 months or prior coronary artery bypass surgery
10. presence of known diabetes (with typical symptoms of ACS)
11. chronic kidney disease (estimated glomerular filtration rate less than 60 mL/minute) (with typical symptoms of ACS)


Intermediate risk features

Presentation with clinical features consistent with ACS and any of the following intermediate-risk features AND NOT meeting the criteria for high-risk ACS:
1. chest pain or discomfort within the past 48 hours that occurred at rest, or was repetitive or prolonged (but currently resolved)
2. age more than 65 years
3. known coronary heart disease—prior myocardial infarction with left ventricular ejection fraction 0.40 or more, or known coronary lesion more than 50% stenosed
no high-risk changes on electrocardiography (see high-risk features above)
5. two or more of the following risk factors: known hypertension, family history, active smoking or hyperlipidaemia
6. presence of known diabetes (with atypical symptoms of ACS)
7. chronic kidney disease (estimated glomerular filtration rate less than 60 mL/min) (with atypical symptoms of ACS)
prior aspirin use


Acute management of NSTEMI

Initial assessment->ECG
02 2-4 L aim >94%
IV access->bloods
Analgesia + antiemetic
GTN spray

High risk:
Aspirin 100-150mg
Clopidogrel 75mg following initial loading 600mg
Metoprolol/verapamil/diltiazem, statin, ACEi
High risk, abnormal ECG or +ve troponins:Tirofiban

-->Angiogram planned: bivalirudin
-->No angiogram: fondaparinux

In intermediate->monitor and reassess (inc cardiac biomarkers)
Low risk->cardiac assessment to rule of CAD->stress testing


Consderations post-thrombolysis

Allergic reaction
Reduced GCS


Complications post-MI

Pulmonary edema
VSD, papillary muscle perforation


Patient instructions

D/C after 5-7 days if uncomplicated
May return to work after 2 months->if heavy labour, need lighter work
Diet high in oily fish, fruits, vegetables, fibre. Low saturated fats
Exercise regularly, lose weight
Intercourse best avoided for a month
Avoid air travel for 2 months
R/V 5 weeks post MI->symptoms
R/V at 3 months->check lipids, glucose, BP etc


A timeline of common post-MI complications

First day: Heart failure.
2–4 days: Arrhythmia, pericarditis.
5–10 days: Left ventricular wall rupture (acute pericardial tamponade causing electrical alternans, pulseless electrical activity), papillary muscle rupture (severe mitral regurgitation).
Weeks to months: Ventricular aneurysm (CHF, arrhythmia, persistent ST-segment elevation, mitral regurgitation, thrombus formation).


Indications for CABG

Unable to perform PCI
Left main CAD
Triple vessel disease
Depressed ventricular function