myocardial ischemia

Question 1

what is myocardial ischemia

Answer 1

build up of atherosclerotic plaques that restrict arteries reducing blood and oxygen to heart

Question 2

stable angina initial treatment and long-term prevention

Answer 2

predictable chest pain/pressure due to physical/emotional exertion

initial:
- can be used prophylactically or when symptoms arise
- GTN - dose every 5 mins
- if symptoms haven’t resolved after 5 mins of 2nd dose - call 999 medical emergency

long term prevention:
1st line - BB or CCB
2nd line - try other class
3rd line - BB + CCB (amlodipine, lacidipine)

4th line - long acting nitrate -
- ivabradine,
- ranolazine - QT prolongation
- nicorandil - GI/mucosal ulceration

implement healthy lifestyle, introduce aspirin 75mg, low dose statin, ACE-i

Question 3

nitrates imp points

Answer 3

GTN sublingual tabs - should be discarded 8 weeks after opening bottle

develop tolerance to nitrates:
- pts should have nitrate free period to prevent tolerance
- instead of normal BD dosing 12hrs after - pts should have 2nd dose 8hrs after 1st
- in transdermal use - patches should be left off 8-12hrs a day

maintain nitrate free period for 10-14 hours
- MR preparations if can’t tolerate asymmetric dosing

SE’s:
- dizziness, flushing, headache
- caution in elderly due to risk of falls

Question 4

major risk factors of ACS

Answer 4

ACS - unstable angina, NSTEMI, STEMI

risk factors:
- family history
- hypertension
- hypercholesterolaemia
- smoking
- diabetes

similar initial and secondary treatment for all 3 - but STEMI needs PCI within 2 hours of happening

Question 5

initial management of ACS

Answer 5

confirmed ACS:
- aspirin loading 300mg
- pain relief: GTN +/- IV morphine
- oxygen if needed - low saturation <94%
- insulin if hyperglycaemia

from test results - determine if unstable angina, NSTEMI or STEMI
- NSTEMI and unstable have partial blockage of artery - ONLY NSTEMI has myocardial necrosis

• STEMI - complete blockage of artery causing necrosis

NSTEMI - ST zone of ECG not elevated
STEMI - ST elevated

Question 6

PCI

Answer 6

percutaneous coronary intervention
- done within 2 hrs of fibrinolysis
- heparin if PCI via radial acess
- prasugrel if not already on anticoagulant
- clopi if alr on anticoagulant

Question 7

secondary prevention of ACS

Answer 7

DAPT:
- aspirin lifelong
- 12 months: clopidogrel, prasugrel or ticagrelor

ACE-I - ARB if ACE-i c/i

BB - may be discontinued after 12 months in pts w/o reduced LVEF

statin - high strength - atorvastatin 80mg
- whereas in stable angina low strength

pt with NSTEMI - might consider PCI to prevent future MI