ACS Flashcards
What is angina and what are the features?
This is symptomatic reversible myocardial ischaemia
Features:
-Constricting/heavy discomfort to the chest, neck, jam and arms
-Symptoms brought on by exertion
-Symtoms relieved by 5 mins rest or gtn spray
What are the causes of angina?
Atheroma Rarely: -anaemia -coronary artery spasm -tachyarrhythmias -small vessel disease
What are the types of angina?
Stable angina - induced by effort, relieved by rest, good prognosis
Unstable angina - gradually increased frequency and severity, increased risk of MI
Decubitus angina - precipitated by lying flat
Vasospasm angina - caused by coronary artery spasm
What tests should be done for angina to rule out other causes?
ECG usually normal, may show st changes
Bloods - u and E, thyroid function tests, lipids, hba1c
Echo and chest c xray to rule out other causes
What is the management of angina?
Address exacerbating factors - anaemia, tachycardia (fast AF), thyrotoxicosis
Secondary prevention of cardiovascular disease:
-75mg asprin daily if not contraindicated
-Stop smoking, increase exercise, dietry advice
-Address hyperlipidaemia
-Consider ACE inhibitors e.g. if diabetic
PRN relief - GTN spray
Anti-anginal medication:
-Beta blockers (atenolol) or calcium channel blockers (amlodipine)
-Long acting nitrates (isosorbide dinitrate)
-Other agents (later questions)
When medical therapy proves inadequate can revascularise using PCI or CABG
How does ivabradine work for angina?
It reduces heart rate with minimal impact on BP
How does ranolazine work for angina?
It inhibits the late Na current, this reduces cardiac work and hence oxygen requirement
How does nicorandil work for angina?
K+ channel activator, decerases calcium sensitivity of smooth muscles leading to coronary vasodilation
What are the main investiagtions for ischaemic heart disease?
Exercise ECG - assess for ECG changes
Angiography - can be contrast CT or transcatheter angiography (invasive but can be combined with stenting)
Functional imaging e.g. stress echo, cardiac MRI
What is the difference between myocardial infarction and ischaemia?
Myocardial infarction is when there is myocardial cell death and troponin release
Ischaemia has a lack of blood supply with or without cell death
What are the risk factors for ACS?
Smoking Poor diet Reduced exercise Family history Male gender Age Hypertension Diabetes Obesity
How is ACS diagnosed?
Combination of raised cardiac biomarkers (troponin) and either:
- symptoms of ischaemia
- ECG changes of new ischaemia
- New loss of myocardium
- Structual changes on imaging
What are the signs and symptoms of ACS?
Central chest pain lasting greater than 20 mins
Associated nausea, dread, dyspnoea, palpatations
Can present siltently with no symptoms or syncope, pulmonary oedema etc.
Signs include - pallor, sweatiness, pulse up or down, BP up or down, signs of heart failure, later may be pericardial rub or peripheral oedema
What tests should be done to investigate ACS?
ECG
Bloods - FBC, U and E, glucose, lipids, cardiac enzymes
CXR - look for cardiomegaly, pulmonary oedema or a widened mediastinum
Echo - regional wall abnormalities
What ecg changes are seen with STEMI?
Hours: -St elevation -Hyperacute tall t waves -New LBBB occurs within hours hours to days:-T wave inversion and pathological q waves
