IHD Flashcards
Describe stable angina
induced by effort, relieved by rest
What type of angina is described by “Occurs at rest or recent onset, increases in severity, high risk of MI”
Unstable angina
When does decubitus angina occur?
When lying down
Angina is mostly caused by atheroma, what are its other causes?
Anaemia Aortic stenosis (AS) Tachyarrhymias Hypertrophic cardiomyopathy (HCM) Arteritis/small vessel disease (microvascular angina/cardiac syndrome X)
Describe the typical chest pain experienced by a patient with angina
Central crushing retrosternal chest pain
Comes on with exertion and relieved upon rest
Radiates to arms and neck
Exacerbated by: cold weather, anger, excitement, heavy meals
Other than chest pain what other symptoms are associated with angina?
sweatiness, dyspnoea, faintness and nausea
What are the different causes of chest pain?
Angina MI Pericarditis Acute coronary syndrome MSK GORD Pulmonary embolism Myocarditis Aortic dissection
An ECG in a patient with angina is usually normal, however when a patient is experiencing an acute attack it will show signs of ischaemia. What are these signs?
ST depression
T wave inversion
If a patient is suffering asymptomatic pain and has no risk factors for angina, further testing is required. What tests are these?
Exercise ECG and functional imaging (coronary angiography
What ECG signs in an exercise test indicate a positive result? A positive test is an indication for further angiography
ST depression at low workload
Paradoxical fall in blood pressure with increased work load.
If a patient is unable to do an exercise test what alternative is often undertaken?
Drug induced stress test
What secondary preventative measures are taken in patients with angina, to prevent MI, stroke ect.
Risk factor modification
Low dose aspirin (75mg daily)
Clopidogrel is an aspirin alternative
Lipid-lowering agents – statins, fibrates
How does aspirin work as an anti-platelet
inhibits COX2 and formation of thromboxane A2 (platelet aggregating agent)
Clopidogrel is alternative to aspirin, how does it work?
P2Y12 receptor inhibitor
What symptomatic treatment is offered to patients with angina?
Sublingual GTN spray for acute attacks
β-blockers – e.g. atenolol, metroprolol.
Calcium channel blockers (calcium antagonists) e.g. diltiazem, amlodipine
Nitrates e.g. isosorbide mononitrate, slow release preparations may be given for prophylaxis
What is a common side effect of GTN spray
severe headache
What are contraindications to B Blocker usage
ASTHMA, COPD, LVF, bradycardia, coronary artery spasm.
What is effect of Calcium channel blockers
Relaxes the coronary arteries and reduces force of LV contraction, thus reducing oxygen demand.
What is a Percutaneous coronary intervention (PCI)?
catheter inserted, balloons used to dilate atheromatous areas of arteries. Stents can be placed.
When preforming a PCI what drugs should be given to reduce risk of a) clotting b) procedure related ischaemic events?
a) clopidogrel (anti-platelet)
b) IV glycoproteins IIb/IIIa inhibtiors (e.g. eptifibatide)
What disease does acute coronary syndrome cover?
Unstable angina
NSTEMI
STEMI
Describe the common pathology to acute coronary syndrome caused by atheroma (main cause)
Rupture/ erosion of fibrin rich cap on a coronary artery atheromatous plaque. (Rupture more likely with a lipid rich core)
Formation of a platelet rich clot
Vasoconstriction produced by platelets releasing thromboxane A2 and serotonin
How is an unstable angina differentiated from NSTEMI
NSTEMI will show rise in Troponin and creatine kinase
What are non modifiable risk factors for ACS?
Age
Male
FHx of IHD (MI in 1st degree relative <55yrs)
Describe the clinical presentation of acute coronary syndrome
Acute central chest pain >20mins
Dyspnoea
Palpitations
Pallor, sweatiness
Signs: Pulse may be high or low
BP high or low
4th heart sound
What test should be done on a patient experiencing acute coronary syndrome?
Bloods- FBC, U&E, glucose, lipids
ECG
Cardiac enzyme test
What ECG changes are expected in a patient with acute coronary syndrome?
Hyperacute (tall) T waves
ST elevation (if STEMI)
ST depression in NSTEMI/unstable angina
New LBBB (S shape in V1 and V2 , M in V5 and V6 and broad QRS)
Over the next hrs-days = T wave inversion, pathological Q waves
What enzymes are measured to assess cardiac damage ?
Troponin (T and I) (specific)
Creatine kinase (non specific)
Myoglobin
What does MONA(T) stand for with regard to the treatment of acute coronary syndrome
Morphine Oxygen Nitrates Aspirin (T)- if severe ticragelor or clopidogrel
Metoclopramide is often given with morphine or diamorphine, what is its purpose?
Anti- emetic
Anti- anginal therapy is important in the long term management of acute coronary system, what does this include?
beta blocker, nitrates, calcium antagonist
What is fondaparinux?
anti coagulant- factor 10a inhibitor, interferes with thrombus formation at the site or Heparin
Describe clinical presentation of an acute stemi
Central crushing chest pain, similar to angina
Differs from angina as: occurs at rest, is more severe, lasts up to several hours
Sweating, breathlessness, nausea, vomiting, restlessness
Patient appears pale and grey
Diagnostic tests and results for acute STEMI
Take brief history to ID risk factors
ECG- will show: Tall, peaked T waves ST elevation After a few hours T waves invert Pathological Q waves develop Will return to normal eventually, although Q waves remain – may take months for T waves to return to upright
Bloods- cardiac enzymes
Xray if there is time
Changes are typically confined to leads that are “looking at” the infarcted area and opposite leads show reciprocal change.
What leads would demonstrate an inferior infarct
2, 3 and aVF= inferior infarct
Changes are typically confined to leads that are “looking at” the infarcted area and opposite leads show reciprocal change.
What leads would demonstrate an anterior infarct?
V2-V6
Changes are typically confined to leads that are “looking at” the infarcted area and opposite leads show reciprocal change.
What leads would show a lateral infarct
1, 2 and aVL show lateral infarct
From hospital admission, how would you manage an acute STEMI
1) attach ECG and record
2) Establish IV access, bloods for- FBC,U&E, glucose, lipids, cardiac enzymes
3) Brief assessment: risk factors for CVS disease. Assessment of pulse BP ect. Check for contraindications for PCI or fibrinolysis
4) Aspirin 300mg (unless already given by paramedics)
5) Morphine + metoclopramide IV
6) If STEMI on ECG and PCI available within 120mins—> PCI . If not—> Fibrinolysis, then transfer to PCI centre.
When managing an acute STEMI, what should you do to prevent hyperglycaemia (glucose >11mmol/L)?
Hypoxia?
Tachycardia
insulin infusion
Oxygen
B blocker
