SIHD and Angina - Therapy Flashcards
what is Clopidogrel
anti platelet agent used in the secondary prevention of atherosclerosis disease and embolic events
beta blockers are reversible antagonists, what receptors do they act on
B1 B2
newer drugs that have a similar action to beta blockers can be described as cardioselective in their action, what receptors are they most likely to act on
the B1 receptors
what are the two agents that beta blockers block the response to in the body
adrenaline
noradrenaline
(the sympathetic system)
beta blockers decrease 3 major determinants of myocardial oxygen demand, what are these 3 determinants
heart rate
contractility
systolic wall tension
what is the “Rebound Phenomena” with sudden cessation of beta blockers
sudden cessation of beta blocker therapy may precipitate myocardial infarction
what are some contraindications of giving beta blockers
asthma
peripheral vascular disease
Raynauds syndrome
heart failure (those patients who are dependant on sympathetic drive)
what is peripheral vascular disease or (PAD)
condition in which build-up of fatty deposits in the arteries restricts blood supply typically to the leg muscles
what do negative inotropes do to heart beat
weaken the force of the heart beat, weakening the contraction and slowing the hearts rate
what are 3 examples of calcium channel blockers
Diltiazem
Verapamil
Amlodipine
what do calcium channel blockers do
Prevent calcium influx into myocytes and smooth muscle lining arteries and atrerioles by blocking the L-Type calcium channel
calcium channel blockers reduce afterload, why is this
CCB reduce vascular tone and so cause vasodilation causing a reduce in afterload
why should you NEVER use Nifedipine immediate release
Evidence that the use of rapidly acting vasodilatatory-CCBs (nifedipine) may precipitate acute MI or stroke
what are some adverse drug reactions of calcium channel blockers
ankle oedema
headache
flushing
palpitation
how do nitrovasodilators cause vasodilation
The nitrovasodilators relax almost all smooth muscle by releasing NO which then stimulates the release of cGMP whch produces smooth muscle relaxation.
GNT is a nitrovasodilator it is commonly given for the rapid treatment of angina pain by sublingual route, why
to avoid first pass metabolism it is given sublingual
when are intravenous nitrates used
they are the main stay in treatment of unstable angina
what is heparin
an aticoagulant (blood thinner) that prevents the formation of blood clots
what vasodilator is it common to develop a tolerance to
nitrates
what is an example of a potassium channel blocker
Nicorandil
what do potassium channel blockers do
activate “silent” potassium channels, the entry of potassium into cardiac myocytes inhibits the calcium influx and so has a negative inotrophic effect.
why is potassium channel openers now a third line treatment
bowel ulceration
what is Asprin commonly used as
antiplatelet agent
what does Ivabradine do
If channel inhibitor it slows the diastolic repolarisation slope of the SA node results in a REDUCTION in heart rate
