Ischemic Heart Disease: Unstable angina (Complete) Flashcards
Define unstable angina
Myocardial ischaemia at rest or on minimal exertion in the absence of acute cardiomyocyte injury/necrosis.
What are typical ECG findings in patients with unstable angina in comparison to MI? (5)
No evidence of ST-elevation MI
ECG may be normal
ECG may show transient ST-elevation
ECG may show ST-deppresion
ECG may show T-wave inversion
N.B. The ECG must not show changes from previous ECG readings. If it does, points towards other causes
How does unstable angina compare to MI in terms of troponin findings?
Unstable angina shows no cardiac troponin elevation (indicating no cardiomyocyte injury or necrosis).
MI would show elevated levels
What is the most common underlying cause of acute myocardial ischaemia (e.g. unstable angina)?
Coronary artery disease
A less common/rare cause of acute myocardial ischaemia characterised by intense vasospasms of the coronary arteries is known as?
Varient angina or Prinzmetal’s angina
MI can also display a normal or non ST-elevated ECG. This subtype of MI is known as?
NSTEMI (Non-ST elevation myocardial infarction)
How can a NSTEMI and unstable angina be differentiated?
NSTEMI would show elevated troponin levels whereas unstable angina would show no elevation.
An acute coronary syndrome (e.g. unstable angina, MI) should always be suspected in patients presenting with which key features? (4)
Must have presented with acute chest pain which includes pain in other areas (e.g. neck, jaw, arm) and any of these features:
Pain has lasted more than 15 minutes
Associated symptoms including: Nausea, vomitting, sweating, breathlessness
New in onset or occurs in patient with known history of stable angina
How is unstable angina chest pain typically described as being?
Pressure
Tightness
Burning
What are some atypical presentations of unstable angina that should be considered? (5)
Epigastric pain
Indigestion
Isolated dyspnoea
Isolated syncope
Back pain (Middle/Upper) [Typical in woman]
Atypical presentations of unstable angina chest pain is most common in which groups of patients? (4)
Woman
Diabetes
Chronic kidney disease
Dementia
What 8 investigations should always be ordered in patients suspected of having an acute coronary syndrome?
_Bedside_:
ECG
Basic obs: Haemodynamic status
Bloods:
FBC (check for anaemia and estimate risk of bleeding)
CRP (check for infective cause of aute chest pain such as pneumonia)
U&Es (determine choice of anticoagulant)
LFTs (assess bleeding risk)
Troponin
Glucose
Imaging:
CXR: Rule out other causes (e.g. pneumothorax, aortic dissection_
What essential questions must be asked when taking the history of patients presenting with acute chest pain? (4)
Is the patient experiencing the chest pain now and if not when was the last episode? (helps to determine timing of high troponin sensitivity).
History and character of chest pain including: Have they experienced this type of pain before?
SOCRATES.
Check for risk factors
Previous investigations for chest pain
List some risk factors for unstable angina (12)
Diabetes
Hyperlipidaemia
Hypertension
Metabolic syndrome
Renal impairment
Peripheral arterial disease
A history of ischaemic heart disease and any previous treatment
Obesity
Advanced age
Smoking
Cocaine use
Physical inactivity
List some risk factors for unstable angina (12)
Diabetes
Hyperlipidaemia
Hypertension
Metabolic syndrome
Renal impairment
Peripheral arterial disease
A history of ischaemic heart disease and any previous treatment
Obesity
Advanced age
Smoking
Cocaine use
Physical inactivity
What 3 medications should be checked for before administering treatment to patients suspected of unstable angina?
Anticoagulants
Antiplatelet drugs
Recent use of phosphodiesterase inhibitors (sildenafil, vardenafil, or tadalafil) [Used in COPD, BPH, erectile dysfunction)
What allergies should be checked for in patients suspected of having unstable angina before treating them?
Check for hypersensitivity to aspirin
What are typicial presentations that can be found on physical examination of patients suspected of unstable angina?
Physical examinations may be normal however some patients may have significant sweating
What findings on physical examination are very atypical in patients with unstable angina and should instead drive suspicion more towards an acute MI? (3)
Low blood pressure
Evidence of left ventricular failure
Life threatnening arrythmias (e.g. ventricular tacchycardia or fibrilation)
What is a typical presentation of chest pain caused by unstable angina?
Pain is retrosternal
Described as pressure, tightness or burning
Radiating to the left arm, both arms, right arm, neck, or jaw.
Pain can be consistent or intermittent
List examples of differentials to consider in patients with unstable angina (8)
Stable angina
Myocardial infarction (STEMI and non-STEMI)
Congestive heart failure
Aortic dissection
Pericarditis
Myocarditis
Pulmonary embolism
Chest wall pain
Pneumothorax
Perforated abdominal viscus
How does the presentation of stable angina differ to unstable angina? (3)
Pain occurs only in context of exertion or emotional stress
Pain is not worsened over time
Pain is relieved by nitrates or rest
How does the presentation of MI differ to unstable angina?
Clinical presentations may be indistinguishable so must be ruled out via investigations (e.g. CXR, troponin)
How does the presentation of congestive heart failure differ to unstable angina? (2)
Presents more predominantly with SoB, Dysponoea, Orthopnea.
Chest pain my occur if coronary perfusion is poor
How does the presentation of chest wall pain differ to unstable angina? (3)
Pain replicated on movement or palpation.
Pain not relieved by rest or nitrates but may be relieved by local injection of lidocaine
How does the presentation of pericarditis differ to unstable angina? (4)
Pain relieved when sitting up and leaning forward.
Pain worsened when supine
Pericardial rub may be heard
Have history of recent myocardial infarction, renal failure, chest irradiation, or associated connective tissue disease.
How does the presentation of myocarditis differ to unstable angina?
May have had a recent viral infection
Chest pain is sometimes pleuritic
More likely to present with signs of heart failure (e.g. peripheral oedema, dyspnoea), palpitations or fatigue
How does the presentation of aortic dissection differ to unstable angina? (3)
Chest pain is often tearing and radiates to the back between the shoulder blades
May have a medical history of hypertension, Marfan’s or Ehler’s Danlos syndrome.
May have radio-radial delay, diastolic murmur or aortic regurgitation
How does the presentation of a pulmonary embolism differ to unstable angina? (3)
Present with acute presentations of SoB, pleuritic chest pain or syncope.
May present with hypoxia, cyanosis, elevated jugular venous pressure with hypotension, and clear lung fields.
May have a history of: Recent surgery, immbolisation, air travel, cancer
How does the presentation of a pneumothorax differ to unstable angina? (3)
Acute chest pain with shortness of breath
May have tracheal deviation, hyperesonance of decreased breath sounds.
Underlying lung disease, trauma, or recent procedures (such as insertion of central venous line).
How does the presentation of a perforated abdominal viscus (aka bowel peforation) differ to unstable angina? (3)
Typically presents with abdominal pain. Chest pain is referred but may be mistaken for cardiac origin.
Abdominal examination shows localised tenderness and, in cases of peritonitis, generalised tenderness.
History of previous peptic ulcer disease, diverticulitis, or recent bowel biopsy.
N.B. CXR also shows gas bubble under diaphragm
What is the initial management plan for patients presenting with unstable angina? (5)
1) Oxygen (if sats are <90)
2)300mg Aspirin + Fondaprinux (antithrombin) (Check for allergies or significant bleeding risk)
3) Calculate GRACE (6-month mortality predictor)
4) Translingual/sublingual glyceryl trinitrate (pain relief)
For low risk mortality:
Low bleeding risk: Aspirin + ticagrelor
High-bleeding risk: Aspririn + clopidogrel (P2Y12 inhibitor)
For intermediate/high risk mortality:
Haemodynamically unstable: Immediate angioplasty
Haemodynamically stable: ticagrelor + aspirin with follow-up angioplasty within 72 hours
Replace tricagrelor with prasugrel if undergoing a PCI (angioplasty with stenting)
Name the antithrombin initially administered to patients with unstable angina
Fondaprinux
Name the painkiller administered to patients with unstable angina
glyceryl trinitrate
List 2 examples of types of P2Y12 inhibitors
Clopidogrel
Prasugrel
Prasugrel has higher bleeding risk than clopidogrel
What is the long term management plan for patients with unstable angina?
Supportive:
Cardiovascular risk factor modification (e.g. lifestyle/diabetes/lipids)
Medical:
Beta-blocker (e.g. bisoprolol) or CCB (e.g. verapamil).
Discuss cardiovascular disease risk factor modification
Increase dosages of the medications if patient already taking them
How can a patient’s risk of bleeding be assesed before adminsitering aspirin or anticoagulants (e.g. fondaprinux)?
HAS-BLED score
Administraton of aspirin and fondaprinux/PY2Y12 inhibitor in patients suspected of unstable angina is known as?
Dual anti-platelet therapy
What tool can be used to predict prognosis for patients with acute coronary syndrome?
GRACE score
What is considered low risk and intermediate/high risk based on GRACE scores?
Low risk is 6 month mortality less than or 3%
Intermediate/High risk is 6 month mortality greater than 3%
What are 2 complications that can occur when treating patients with unstable angina?
Bleeding
Thrombocytopenia
What are 2 complications that can arise in patients with unstable angina?
Congestive heart failure (Chronic ongoing ischaemia can cause myocardial damage overtime)
Ventricular arrythmias (tacchycardia and fibrilations)
