T3 L14: Treatment for ischaemic heart disease Flashcards
What are the 2 main sources of cholesterol?
Up taken from the GI tract or produced by the liver
How do statins reduce blood cholesterol?
They inhibit the HMG CoA reductase enzyme which causes the liver to express more LDL receptors. The receptors are used to up take LDL cholesterol from the blood by liver cells
What is HMG CoA reductase responsible for?
It catalyses the rate determining step in cholesterol synthesis
What is the drug clopidigrel for?
Antiplatelet
What type of drug is Ramipril?
An ACE inhibitor
What type of drug is Losartan?
An angiotensin receptor blocker (ARB)
What is the treatment for acute coronary syndromes like unstable angina, NSTEMI and STEMI?
As for stable angina but with antiplatelets because their plaques are unstable and likely to rupture (Aspirin + Clopidogrel)
What is an NSTEMI?
Non-ST segment elevation myocardial infarction
What is a STEMI?
ST-segment elevation myocardial infarction
What type of drug is Prasugrel?
An anti-platelet usually used alongside aspirin (an ADP antagonist that blocks P2Y12 receptors). It’s irreversible
What type of drug is Ticagrelor?
An anti-platelet (P2Y12 inhibitor). It’s effects are reversible
How are platelets activated?
Endothelial cells are damaged so ADP is released and it acts on P2Y12 receptors to stimulate platelets to express GP2b/3a receptors. Fibrinogen binds to these receptors to cross link different platelets
How does aspirin work?
It inhibits COX (cyclo-oxygenase enzyme) irreversibly
How does Clopidigrel work?
It’s an ADP antagonist that blocks P2Y12 receptors. Irreversible
How does activation of COX help platelet activation?
Through the production of Thromboxane A2
Sweating, tachycardia and cold clammy skin are a marker of what?
An overactive sympathetic NS
What causes clammy skin?
Constricted vasculature in an effort or raise blood pressure
How does an MI cause a decrease in blood pressure?
It causes damage and an impaired cardiac output which will cause a lowered BP
In which part of the body is low blood pressure detected?
The medulla oblongata of the brain
What causes sweating, tachycardia and cold, clammy skin symptoms during angina?
The heart is damaged during an MI and this decreases cardiac output. The sympathetic NS is activated to counteract the pressure loss
Why is oxygen given as a treatment for angina?
It minimises further damage
What is GTN?
Glyceryl trinitrate
How does GTN work?
It’s a nitrate so it causes vasodilation and this increases blood supply to areas like the heart where the was previously a blockage
What is Tenecteplase and what is it used for?
An enzyme used as a thrombolytic drug
What is the function of plasmin?
Break down of fibrin
What is the difference between fibrin and fibrinogen?
Fibrin is made from fibrinogen. Fibrinogen is converted at the wound into fibrin by the action of thrombin
What is the name of factor 1?
Fibrinogen
What is the function of Thrombin?
It converts fibrinogen into fibrin at the site of a wound
What is the medical form of heroin called?
Diamorphine
How are beta blockers used in cardiac treatment
They decrease cardiac workload by reducing heart rate, contractility, and arterial pressure. This reduces the O2 demand
What is metoprolol and when is it administered?
A short-acting beta-blocker administered in a hospital setting because the dosage can easily be adjusted.
What is bisoprolol and when is it administered?
A long-lasting beta-blocker administered in the community
How are ACE inhibitors used in cardiac treatment?
They reduce cardiac workload and prevent remodelling development of heart failure
What type of drug is Tinzaparin?
An anticoagulant (A low molecular weight heparin)
What type of drug is Warfarin?
An anticoagulant
What type of drug is Apixaban?
An anticoagulant
What type of drug is Rivaroxaban?
An anticoagulant
What type of drug is dabigatran?
An anticoagulant
What is the mechanism of action of Digoxin?
It inhibits the Na+/K+ ATPase by binding to it. The levels of Na+ inside the cell increase and this causes the inhibition of the Na+/Ca2+ exchanger leading to a build of of Ca2+ inside the muscle cells and therefore a stronger contraction
What is Digoxin used to treat?
Heart failure (makes contractions stronger)
