Angina, Unstable angina, NSTEMI and STEMI Flashcards
Explain Stable Angina
Angina is a symptom, not a condition (i.e. not ACS) Angina is a discomfort/pain in the chest with/without pain in adjacent areas (jaws, shoulder, neck). The pain is caused by a lack of oxygen supply to the heart (myocardial ischaemia), due to coronary heart disease and narrowing of the coronary arteries.
Angina is a predictable pain precipitated by physical exertion or emotions. It is a restrictive discomfort of the chest that is relieved by rest and a GTN spray within 5 minutes.
Angina can be associated with dyspnoea, sweatiness , nausea, and fainting
What are the 9 modifiable risk factors for Angina/ACS?
- Hypertension
- Smoking
- Poor Diet
- Higher cholesterol
- Diabetes
- Insufficient physical activity
- Overweight/obese
- Psychosocial stress
- Excess alcohol consumption
Management/treatment of stable Angina
- ECG (to rule out ACS)
- Offer a CT coronary angiogram
- Offer GTN spray
- Offer anti-anginals e.g. B-Blockers, CCB’s
- Offer secondary prevention e.g. ACEi
- Offer Statin
- Offer other anti-hypertensives
- Consider revascularisation
- Modify risk factors - smoking cessation, improved diet, regular exercise, controlled diabetes
Briefly describe the 4 types of angina
Stable angina = induced by effort, relieved by rest
Unstable angina = Angina of increasing frequency and severity, occurs on minimal exertion and is associated with increased risk of MI
Decubitus angina = Precipitated by lying flat
Variant (Prinzmetal’s) angina = Caused by coronary artery spasm. ECG show ST elevation when in pain, but resolves as the pain subsides. Patients often do not have the standard risk factors for atherosclerosis. Treatment is with CCBs and long-acting Nitrates. Aspirin and B-blockers should be avoided.
Explain ACS
ACS is an umbrella term used to describe clinical symptoms compatible with acute myocardial ischaemia e.g. unstable angina, NSTEMI and STEMI.
Explain Unstable angina
- Patients with ischaemic symptoms suggestive of ACS
- No elevation in troponin
- With/without ECG changes
- Occurs at rest/minimal exertion
- Severe and of new onset
- Crescendo pattern: Less activity, more severity, increased duration and increased frequency
Management of Unstable Angina
Aspirin (300mg) / Clopidogrel
Fondaparinux / Unfractionated heparin
Ticagrelor
Risk factor management
- Smoking cessation
- Diet changes/ statins
- Exercise + weight loss
- Anti-hypertensives
- Revascularisation
Explain NSTEMI
- Patients with ischaemic symptoms suggestive of ACS
- Partial blockage of coronary artery
- Elevated troponin
- No ST elevation on ECG
- Occurs at rest
Management of NSTEMI
Aspirin (300mg) / Clopidogrel
Fondaparinux / Unfractionated heparin
Ticagrelor
Risk factor management
- Smoking cessation
- Diet changes/ statins
- Exercise + weight loss
- Anti-hypertensives
- Revascularisation
Explain STEMI
- Patients with ischaemic symptoms suggestive of ACS
- Complete blockage of a coronary artery
- Elevated troponin and 1 of the following:
- ST elevation on ECG
- ECG: development of pathological Q waves
- Ischaemic symtpoms
- Echo: Loss of viable myocardium
Anterior MI = Leads V2-5
Lateral MI = Leads V5, V6, I, and aVL
Inferior MI = Leads II, III and aVF
Management of a STEMI
Coronary perfusion therapy
Coronary angiography and percutaneous coronary intervention
Coronary artery stents
Cardiac rehabilitation
- Smoking cessation
- Diet changes/ statins
- Exercise + weight loss
- Anti-hypertensives
- Revascularisation
Complications of an MI - Reduced contractility
- Reduced contractility
The heart is less able to contract and expel blood. This results in HYPOTENSION and therefore decreased coronary artery perfusion. This results in additional ischaemia in other area and further reduces the contractility. Eventually the patient is unable to maintain cardiac output and will develop CARDIOGENIC SHOCK.
Blood stasis due to decreased contractility increases the likelihood of a THROMBUS/EMBOLI FORMATION.
Complications of an MI - Tissue necrosis
After an MI there is an inflammatory response and an increase in immune cell. Inflammation can irritate the pericardium and result in PERICARDITIS.
Necrosis of the septum allows oxygenated blood and deoxygenated blood to mix across the necrotic septum and cause SEVERE HYPOXAEMIA.
A ventricular septal defect can cause blood to flow from a high pressure system (LV) to a low pressure system (RV) and cause PRESSURE DAMAGE TO THE PULMONARY VESSELS.
Necrosis of the ventricular wall can cause VENTRICULAR RUPTURE - this allows blood to collect in the pericardial sac, CARDIAC TAMPONADE, which increases cardiac stress and further reduces contraction
Papillary muscle necrosis causes CUSP EVERSION and consequently blood re-enters the atria - MITRAL/TRICUSPID REGURGITATION.
Complications of an MI - Electrolyte instability
Electrical instability can cause ARRHYTHMIAS. This si either due to
- DISORGANISED MOVEMENT OF IONS in cardiomyocytes
- DISRUPTION TO CONDUCTION SYSTEM
Complications of an MI - OVERALL
If the heart had decreased contractility, mitral regurgitation or ventricular septal defect, ti has to work harder to maintain proper perfusion around the body. Therefore, these 3 complications increase the risk of developing CONGESTIVE HEAR FAILURE.
