Angina Flashcards
What is angina?
a discomfort in the chest and/or adjacent areas associated with myocardial ischaemia but with no myocardial necrosis
What is the pathophysiology of angina?
Mismatch between oxygen supply and metabolites supply to myocardium and the myocardial demand for them
What is angina most commonly due to?
-reduction in coronary blood flow to the myocardium commonly caused by an obstructive coronary atheroma
What is angina rarely due to?
reduction in coronary blood flow to the myocardium rarely due to Coronary artery spasm (uncommon, Vasospastic angina) or coronary artery inflammation/arteritis (Rare)
or due to Microvascular angina
What is reduced oxygen transport uncommonly due to?
- Anaemia of any cause
What is increased myocardial O2 demand uncommonly due to?
- Thyrotoxicosis
- Left ventricular hypertrophy which is seen in significant hypertension, aortic stenosis, hypertrophic cardiomyopathy
Explain the effect of coronary atheroma on activity.
- Increased myocardial oxygen demand, but atheroma is causing a blockage for the blood to travel through, therefore causing myocardial ischaemia and thus the symptoms
What kinds of activity trigger angina
- emotional distress, anxiety, eating after a huge meal, physical activity, cold weather
How much of the plaque needs to cover the lumen for symptom, and how does atherosclerosis form?
- > 70%
- Fatty streak -> non obstructive plaque-> obstructive plaque.
- Atherosclerosis is a progressive process which builds up over icnreasing age.
How does stable angina differ from acute coronary syndrome?
- The plaque is stable but in ACS, there is spontaneous ruptured plaque and local thrombosis, with degrees of occlusion
How to diagnose angina?
- Relived immediately after GTN spray or rest.
- retrsternal chest pain spreading to arms, neck, jaw
- “heavy” “tight band” “pressure” pain
- aggravated by trigger
others:
- near syncope
- dyspnoae
- excessive fatigue
When may it not be angina?
- pleuritic or pericardial chest pain= Sharp, stabbing
- pain continues after rest
- associated with body movements or respiration
- very localised pain
- no pattern pain
- lasts for hours and begins some time after exercising.
What are differential diagnoses to angina?
- cardiovascular
a) Pericarditis b) Aorta dissection - respiratory
a) Pleurisy b) Pneumonia c)Peripheral pulmonary emboli - GI
a) Gastro-oesphageal reflux b) oesophageal spasm c) peptic ulceration d) biliary colic e) cholecystitis.f) pancreatitis - Muscoskeletal
a) Cervical disease b) costochondritis c)muscle spasm or strain
when the other symptoms (excessive fatigue, near syncope, dyspnoea) more common?
- elderly or diabetes mellitus due to reduced pain sensation
What are risk factors for angina?
- modifiable
e. g. Lifestyle (Exercise and diet), Diabetes (glycemic control), Hypertension (controlling reduces CV risk), Hyperlipidaemia (same again) - non modifiable
e. g. Genetic factors, age, gender, fam history
What are the signs of angina>
- tar staining
- xanthalasma and corneal arcus
- obese
- hypertension
- reduced/absent peripheral pulses
- Diabetic retinopathy, hypertensive retinopathy on fundoscopy.
WHAT are signs of exacerbating angina and associated conditions?
- Pallor from anemia
- Tachycardia
- tremor
- mitral regurgitation- Pansystolic murmur
- aortic stenosis- ejection systolic murmur
- heart failure- increased JVP, basal crackles, peripheral oedema
What are investigations for angina?
Blood tests:
a) - lipid profile
b) -FBC
c) -glucose tolerance test
- U&E
- Liver and thyroid test
Myocardial perfusion imaging:
- superior to ETT
- localises ischaemia and how much its affected
- but involves radioactivity
Exercise tolerance test:
- very good
- symptoms + ECG AFTER EXERCISE-ST segment depression
CT coronary angiography:
CXR:
- shows pulmonary oedema and other causes of chest pain
ECG:
- normal in over Half of angina cases
- evidence of previous MI e.g. pathological Q waves
How does myocardial perfusion imaging work?
- needs to happen after exercise or injection of radionuclide tracer at peak stress
- the tracer is present at rest but disappears after strress- Ischaemia
When would you use invasive imaging e.g. coronary angiography
Higher risk patients- determines whether medical treatment or angioplasty or CABG is needed. (Revascularisation is needed if symptoms not being controlled by medication.)
What is more common procedure for revascularisation?
CABG
What is the treatment for stable angina?
- NITRATE gtn spray/ sublingual tablets/patch
- Long acting nitrates isosorbide mononitrate - ASPIRIN
- 75 mg - STATINS
- cholesterol >3.5
- - ## ACE INHIBITORS
- BETA BLOCKER
- bisoprolol - CA CHANNEL BLOCKER
if beta blockers CI
central- Verapamil, diltiazem
peripheral- amlodipine, femlodopine - Ik CHANNEL BLOCKER
- Ivabradine - K CHANNEL BLOCKER
- Nicorandil
If medication doesn’t do enough for symptom control what are the next stepS?
- PCI
- great for symptom control but doesn’t improve prognosis in stable disease
- CABG
- long saphenous vein graft
- better prognosis for- a)70% stenosis left main stem artery and b) significant proximal three vessel CAD c)Two vessel coronary artery disease including the LAD, with EF<50%
- 80% symptom free for 5 yrs but graft deteriorates
What are downsides to botH PCI AND CABG?
Need to continue drug medication
What do Statins do?
- Reduce LDL-cholesterol deposition in atheroma.
- stabilises the atheroma, reduce the chance of Plaque rupture
What do ace inhibitors do?
- Stabilises the endothelium and Reduce the chance of plaque rupture
What does aspirin do?
Reduces platelet aggregation/ activation, protecting the endothelium.
What do beta blockers do?
Reduce the myocardial work , antirhytmicc effects.
What do ik channel blockers do?
-Reduces the Sino atrial rate
