Pharmacology of Angina Flashcards
What is the full name of angina?
Angina pectoris
What is the name of the process of cholesterol rich plaques building up in vessels?
What is the risk of this condition in the:
A) coronary vessels
B) renal arteries
C) carotid arteries
Atherosclerosis
A) MI
B) chronic kidney disease
C) stroke
What are the 2 parts of an atherosclerotic plaque?
Fibrous cap in tunica intima
Atheroma (fatty rich soft core of extracellular lipid)
What happens with time to the atheroma?
It will calcify
Where do plaques usually form with respect to the coronary arteries and surrounding structures?
Within 6cm of the aorta
What are 2 types of plaques and are there and what are the qualities of each?
Which are more likely to turn into which conditions?
Vulnerable plaque - stable angina
= think fibrous cap
= large atheroma
Non-vulnerable plaque - unstable angina, STEMI, NSTEMI (basically ACS)
= thick fibrous cap
= small atheroma
Can the two types of plaques interconvert?
Yes
Name 5 times of angina.
1) angina of effort (stable)
2) mixed (variable threshold) angina
3) Vasospastic (prinzmetal’s) angina
4) microvascular (Syndrome x)
5) unstable
Explain stable angina (of effort).
Occurs with exertion/emotion
Stops with rest or GTN
Results from increase oxygen demand but lack of ability to vasodilate and increase blood flow due to fixed stenosis and a decreased flow reserve capacity
What peptide does hypoxia cardiac cells release and what effect does this have on the body?
Via what channels?
They release bradykinin, activates Trpv1 channels on sensory nerves to cause pain!
How does pain help with angina?
Pain causes substance P release from sensory nerve endings, which include to NK1 Receptors on the vessel walls to cause NO release, therefore substance P is a potent vasodilator which helps to combat angina
Explain vasospastic (primzmetal’s) angina.
No vessel stenosis
Occurs due to vasospasm of the coronary arteries
Happens at night
Rarer
Explain mixed (variable threshold) angina.
A mixture of stable angina of effort and vasospasti (prinzmetal’s)
Unpredictable
Happens at varying levels or exercise
A mix of stenosis and vasospasm
Explain microvascular (syndrome x) angina.
Common in females (hence name)
No stenosis BUT chest pain and positive exercise test
Microvasculature (arterioles) affected NOT macrovasculature (arteries)
Explain unstable angina.
Formation of a non-occlusive thrombus, caused by plaque rupture and thrombus formation.
It an ACS
What is the main aim of drug treatment for angina, and why is this the case?
The main aim is to decrease cardiac oxygen demand and increase the oxygen supply to the ischaemic zone by decreasing heart rate, as vasodilation is NOT an option.
How do the following drugs work and what do they hope to achieve?
1) b-blockers
2) ACE inhibitors
3) aspirin
4) statins
1) decrease inotropy and chronotropy
2) decrease BP and pressures
3) anti-platelet
4) decrease cholesterol
What is the NICE pathway for treatment of stable angina?
1) short acting nitrate for immediate relief
2) beta-blocker AND non-vascular selective CCB
3) beta-blocker and VASCULAR selective CCB
4) beta-blocker and vascular selective CCB AND one of the following:
- long acting nitrate
- ivabradine
- nicorandil (potassium channel activator)
- ranolazine (anti-anginal)
How do nitrates work vascularly?
What effect does this have on the heart?
They venodilate
This decreases cvp which decreases pressures going into the heart, which decreases preload and cardiac oxygen demand