Understanding symptoms and signs Flashcards
What happens to the pH in ishaemic muscle?
Decreases due to lactate production.
What substance is released in response to a pH drop?
Substance P, a neuropeptide
What does substance P do?
Increases the sensitivity to pain afferents in muscle.
Why can young people with normal coronary vessels and thyrotoxicosis develop angina or even MI?
Thyroid hormones increase BMR and HR which will increase the oxygen demand of the cardiac muscle.
Which words can be used to describe pain from ischaemia muscle?
Tight, constricting, heavy, crushing, cramping, pressure.
Where are some of the common sites of referred cardiac pain?
Chest, arms (particularly down the left arm), neck, jaw
Why can angina be brought on by cold weather or a meal?
Cold weather - vasoconstriction
After a meal - blood redirected away from the heart and to the GI tract.
What ECG changes may be present in unstable angina?
ST depression
T wave inversion
Would you expect cardiac markers to be raised in unstable angina?
No.
Unstable angina may be the precursor to _______.
MI
Why is a patient pale and sweaty with cold skin during an MI?
Over-activation of the sympathetic nervous system - vasoconstriction, sweat secretion.
Why do patients suffering from an MI feel nauseated?
Redirection of blood away from GI system
Increase of SNS stimulation
Why are patients suffering from an MI dyspnoeic?
There is reduced CO from the left ventricle, so there is a ‘back up’ of deoxygenated blood in the pulmonary circulation.
What might cause palpitations?
- Heightened awareness of normal heart beat
- Sinus tachycardia
- Atrial or ventricular ectopic beats
- Atrial tachycardias or fibrillation
- Ventricular tachycardia or fibrillation
What is dyspneoa?
Shortness of breath
What is othopnea?
Shortness of breath when lying down
What is paroxysmal nocturnal dyspnoea (PND)?
waking up short of breath during the night
What other disease causes dyspnoea which is worse a night?
Asthma
When does collapse/loss of consciousness occur?
No/low output
Brady/tachycardia which leads to cerebral hypo perfusion
What occurs immediately after recovery from LOC if the cause was arrhythmia?
Flushing
When would you hear an irregularly regular pulse?
2nd degree heart block
When would you hear an irregularly irregular pulse?
ventricular or atrial ectopics
atrial fibrillation
What is pulse pressure?
Systolic pressure - diastolic pressure
What causes a bounding pulse?
Widening of the pulse pressure
Associated with increased SV of LV and decrease in peripheral resistance which lowers the diastolic pressure.
When might you see a bounding pulse?
Bradycardia
Aortic regurgitation
Why is there a bounding pulse with aortic regurgitation?
Blood returning to the LV will mean that less blood is in the periphery, so diastolic pressure will be decreased.§
After a ventricular ectopic, why is the next ‘normal’ beat felt strongly by the patient?
There is a pause following an ectopic beat, increasing the diastolic filling.
When might a pulse be thready?
Shock - cardiogenic, hypovolaemic
LV failure
How does a hot bath, exercise and pregnancy affect the pulse pressure?
Causes vasodilation, lowering TPR so increases pulse pressure.
Why are right-sided murmurs increased during inspiration?
the right side of the heard is being loaded during inspiration
Why are left-sided murmurs increased during expiration?
the left side of the heart is being loaded during expiration
Why ask the patient to hold their breath?
So you can’t hear breathing sounds
Why is S2 usually split on inspiration?
Pulmonary valve closes slightly after the aortic valve because inspiration lowers the intrathoracic pressure, so there is increased venous return to the RV which means it takes longer to empty.
What is buerger’s test used to assess?
The arterial supply to the leg
How is buegers test performed?
Elevate the patients legs, if they go pale then inadequate peripheral arterial pressure to overcome gravity.
Then hang the patients leg down over the bed, should return pink fairly quickly.
Explain why ‘sunset foot’ can be seen in ischaemia?
Foot is paradoxically pink due to vasodilation of arterioles in attempt to get rid of the metabolic waste that has built up during ischaemia.