SIHD and angina Flashcards
What is angina ?
A discomfort in the chest and or adjacent areas associated with myocardial ischaemia but without myocardial necrosis
What is the most common cause of angina ?
Coronary atheroma
What are the most common ways coronary blood flow to the myocardium is reduced ?
Obstructive cornonary atheroma (v common)
Spasm of a portion of cornonary artery (uncommon)
Abnormal coronary flow (uncommon)
What are the uncommon reasons for having stable angina ?
Uncommonly due to reduced O2 transport:
- anaemia of any cause
Uncommonly due to the pathologically increased myocardial O2 demand:
- LVH caused by years of persistant hypertension, significant aortic stenosis or
hypertrophic cardiomyopathy
- Thyrotoxicosis
What is essential in the history of angina ?
Characteristics of pain to differenciate from other causes of chest pain
Where is the site of angina usually ?
Retrosternal
What is the character of chest pain usually ?
Often tight band/pressure/heaviness
Where does the pain usually radiate ?
Neck and jaw and down arms
What are the aggravating factors of chest pain ?
Exertion
Emotional stress
What is the releveling factors of anginal chest pain ?
Rapid improvement with GTN
Physical rest
What are the features that make it less likely to be angina ?
Sharp/stabbing pain: pleuritic or pericardial Associated with body movements or respiration Very localised Superficial with or without tenderness No pattern to pain Begins some times after exercise Lasting for hours
What symptoms on exertion is often assocaited with myocardial ischameia with no chest pain ?
Breathlessness on exertion
Excessive fatigue on exertion for activity undertaken
Near syncope on exertion
What are the differential diagnosis of chest pain ?
Cardiovascular causes:
- aortic dissection, pericarditis
Respiratory:
- pneumonia
- pleurisy
- peripheral pulmonary emboli
Musculoskeletal:
- cervical disease
- costochondritis
- muscle spasms or strain
GI causes:
- gastro-oesphageal reflux
- oesphageal spasm
- peptic ulceration
- biliary colic
- cholecystitis
- pancreatitisWhat does a CCS score of I mean ?
Ordinary physical activity does not cause angina, symptoms only on significant exertion
What does a CCS score of II mean ?
Slight limitation of ordinary activity, symptoms on walking 2 blocks or >1 flight of stairs
What does a CCS score of III mean ?
Marked limitation, symptoms on walking only 1-2 blocks or 1 flight of stairs
What does a CCS score of IV mean ?
Symptoms on any activity, getting washed/dressed causes symptoms
What are the non-modifiable risk factors for coronary artery disease and ASCVD ?
Age Gender (M>F) Creed Family history Genetic factors
What are the modifiable risk factors for coronary artery disease and ASCVD ?
Smoking
Lifestyle- exercise and diet
Diabetes mellitus (glycaemic control reduces CV risk)
Hypertension (BP control reduces CV risk)
Hyperlipidaemia (lowering reduces CV risk)
What are the common examination findings ?
Tar stains on fingers Obesity (centripetal) Xanthelasma and corneal arcus (hypercholesterolaemia) Hypertension Abdominal aortic aneurysm Arteial bruits Absent or reduces peripheral pulses Diabetic retinopathy, hypertensive retinopathy on fundoscopy
What are the signs of exacerbating or associated conditions ?
Pallor or anaemia
Tachycardia, tremor, hyperreflexia of hyperthyroidism
Ejection systolic murmur, plateau pulse of aortic stenosis
Pansystolic murmur of mitral regurgitation
Signs of heart failure such as basal crackles, elevated JVP, peripheral oedema
What investigations can be done ?
Bloods CXR ECG Exercise tolerance test Myocardial perfusion imaging CT coronary angiogram
What blood test might be done ?
FBC
Lipid profile and fasting glucose
Electrolytes
Liver and thyroid tests
What would we look for in a CXR ?
Often helps show other cause of chest pain and can help show pulmonary oedema
What might an ECG be like in angina ?
Normal in over 50% of cases
May be evidence of prior MI i.e. Pathological Q-waves
May be evidence of LVH i.e. High voltages, lateral ST-segment depression or ‘strain pattern’
What is the purpose of an exercise tolerance test ?
Often can conform diagnosis of angina
Relies on ability to walk for long enough to produce sufficient CV stress
Typical symptoms and ST-segment depression for positive test
Negative ETT doesnt exclude significant cornonary atheroma but if negative at high workload overall prognosis is good
What might myocardial perfusion imaging show ?
Superior to ETT in detection of CAD, localisation of ischaemia and assessing size of area affected
Expensive, involves radioactivity: depending on availability used where ETT not possible/equivocal
Either exercise or pharmacological stress: adenosine, dipyridamole or dobutamine
Radionuclide tracer injected at peak stress on one o
When might a tracer be seen at rest but not after stress ?
Ischaemia
When will a tracer never be seen at rest or after stress ?
Infarction
Why is CT angiography useful ?
Possible to image arteries well
They will be moving al the times- limitation
More accurate in pateints with low HR and normal sinus rhythm
When should invasive angiography be used ?
Early or strongly positive ETT (suggests multi-vessel ds)
Angina refractory to medical history
Diagnosis not clear after non-invasive medical therapy
Young cardiac pateint due to work/life effects
Occupation or lifestyle with risk e.g. Drivers
What can cardiac catheterisation/ coronary angiogram show in chronic stable angina ?
Definition of coronary anatomy with sites, distribution and natures of atheromatous disease enables decision over what treatment options are possible
Whether medication alone or percutaneous coronary intervention (PCI) most often angioplasty and stenting or coronary artery bypass graft (CABG) surgery
Almost always done under local anaesthetic
Arterial cannula inserted into femoral or radial artery
Cornonary catheters passes to aortic root and introduced into the ostium of coronary arteries
Radio-opaque contrast injected down coronary arteries and visualised on x-ray
What are the general measures of treatment for angina ?
Address ASCVD risk factors: BP, DM, cholestrol
Lifestyle: physical activity
What drugs can be used to influence disease progress ?
Statins: consider if total cholestrol >3.5mmol/L
- reduces LDL-cholestrol deposition in atheroma and also stabilise atheroma reducing plaque rupture and ACS
ACEI: if increased CV risk and atheroma
- stabilises endothelium and also reduces plaque rupture
Aspirin: 75mg or clopidogrel if intolerant of aspirin
- may not directly affect plaque but does protect endothelium and reduces of platelet activation/aggregation
What drugs can be used for symptom relief of angina ?
B-blockers: acheive resting HR <60bpm
- reduced myocardial work and have anti-arrhythmic effects
Ca2+ channel blockers: acheive resting HR <60bpm
- central acting e.g. Diltiazem / verapamil if B-blockers contraindicated
Ca2+ channel blockers: produce vasodilation
- peripherally acting dihydropyridines e.g. Amlodipine, felodipine
Ik channel blockers: acheive resting HR < 60bpm
- ivabradine reduces sinus node rate
Nitrates: produces vasodilatation:
- used as short or prolonged acting tablets, patches or as rapidly acting sublingual GTN spray
K+ channel blockers: nicorandil
- nitrate molecule and K channel helpful in pre-conditioning
Is symptoms are not controlled what else can be undertaken ?
Revascularisation:
- percutaneous coronary intervention (PCI)
- CABG
