stable angina Flashcards
stable angina
a discomfort in the chest that is associated with myocardial ischaemia and not necrosis
aetiology of angina
mismatch between supply of oxygen and metabolites to the myocardium this is caused by reduced coronary artery blood flow caused by obstructive coronary atheroma
factors that can cause a reduction in artery blood flow
Obstructive coronary atheroma (Very common)
Spasm of a portion of coronary artery (Uncommon)
Abnormal coronary flow (Uncommon).
uncommon causes of angina
anaemia
increased myocardial demand which might be because of left ventricle hypertrophy or stenosis or hypertrophic cardiomyopathy or thyrotoxicosis.
pathophysiology of stable angina
presence of coronary atheroma- there is increased oxygen demand leading to increased blood flow which is obstructed and this leads to myocardial ischaemia and then angina
situations when myocardial oxygen demand increases
exercise , anxiety , emotional stress and after a large meal.
typical distribution of pain or discomfort in stable angina
on the left side of the chest
history of pain for angina
site of pain - retrosternal
character of the pain - often a tight band /pressure /heaviness
radiation sites of the pain - neck / jaw /down the arms
aggravating factors - exertion / emotional stress
relieving factors - physical rest
pain that makes angina less likely
sharp /stabbing pain /pleuritic pain or pericardial
associated with body movements or respiration
very localised pain , where they can pinpoint
superficial with no tenderness
lasting for hours
no pattern to pain
pain after exercise
differential diagnosis
aortic dissection , pericarditis
pneumonia ,pleurisy , peripheral pulmonary emboli
cervical disease , costochondritis , muscle spasm or strain
gastro-oesophageal reflux , oesophageal spasm , peptic ulceration , biliary colic
symptoms of stable angina
breathlessness on exertion
pain on the sternal area with the pain radiating to hands and neck.
near fainting on exertion
excessive fatigue on exertion for an activity that is undertaken.
severity of angina
I-Ordinary physical activity does not cause angina, symptoms only on significant exertion.
II-Slight limitation of ordinary activity, symptoms on walking 2 blocks or > 1 flight of stairs.
III-Marked limitation, symptoms on walking only 1-2 blocks or 1 flight of stairs.
IV-Symptoms on any activity, getting washed/dressed causes symptoms.
examination of stable angina
tar staining on fingers
obesity ( centripedal)
xanthalasma and corneal arcus
hypertension
abdominal aortic aneurysm , arterial bruits(noises ), may be absent reduced or absent
diabetic retinopathy
associated conditions of stable angina
pallor of anemia
tachycardia, tremor , hyperreflexia of hyperthyroidism
ejection systolic murmur , plateau pulse of aortic stenosis.
pansystolic murmur of mitral regurgitation
basal crackles , elevated jugular venous pressure , peripheral oedema
investigations for angina
bloods
lipid profile
fasting glucose
electrolytes
liver and thyroid tests
chest x.ray- useful for other chest diseases esp pulmonary oedema
ECG -normal in most cases , may be evidence of previous MI funny q waves , left ventricle hypertrophy
exercise tolerance test
myocardial perfusion imaging
coronary angiography
ECG in stable angina
left ventricular hypertrophy ie high voltages , lateral ST - segment depression or strain pattern
often can confirm diagnosis of angina
Relies on ability to walk for long enough
to produced sufficient CV stress.
Typical symptoms and ST-segment depression for positive test.
-ve ETT doesn’t exclude significant
coronary atheroma but if negative at high workload overall prognosis is good.
results of exercise tolerance test
ST segment depression
myocardial perfusion imaging
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 .
results of myocardial perfusion imaging
tracer seen at rest but not after stress -ischaemia
tracer seen neither rest , or after stress - infarction
when is an invasive angiography done?
Early or strongly positive ETT (suggests multi-vessel ds).
Angina refractory to medical therapy.
Diagnosis not clear after non-invasive tests.
Young cardiac patients due to work/life effects.
Occupation or lifestyle with risk e.g. drivers etc.
Stable angina
ST segment depression
how is Cardiac catheterisation done
?
coronary catheters are passed to aortic root and introduced into the ostium of coronary arteries
chronic stable vs stable angina
chronic - insertion of arterial cannula and a catheter is passed to the aortic root
treatment for stable angina
CABG , PCI
drugs to reduce disease progression and symptoms
address risk factors such blood pressure , cholesterol , diabetes mellitus
pharmacological treatment for stable angina by reducing disease progression
statin; will reduce LDL cholesterol deposition in atheroma and also reduce atheroma rupturing
ACE inhibitors ; stabilise endothelium and also reduce plaque rupture
aspirin - protects the endothelium and reduces of platelet activation / aggregation
