Therapy for acute coronary syndromes and myocardial infarctions

Question 1

What are the two main goals of ACS therapy?

Answer 1

Increase myocardial oxygen supply

Decrease myocardial oxygen demand

Question 2

What arteries are used for access to carry out PCI?

Answer 2

Femoral or radial

Question 3

Describe the mechanism of action of thrombolytic agents

Answer 3

Are all serine proteases which act by converting plasminogen to plasmin, a natural fibrinolytic agent. Plasmin lyses clots by breaking down the fibrinogen and fibrin contained in the clot

Question 4

Name some fibrin specific thrombolytic agents

Answer 4

Alteplase
Reteplase
Tenecteplase
Alteplase

Question 5

Name a non-fibrin specific thrombolytic agent

Answer 5

Streptokinase

Question 6

Name some contraindications when using thrombolytic agents

Answer 6

Prior intracranial haemorrhage
Known structural cerebral lesion
Known malignant intracranial neoplasm
Ischaemic stroke within 3 months
Suspected aortic dissection
Active bleeding or bleeding diathesis
Significant closed head trauma or facial trauma in last 3 months

Question 7

Describe the mechanism of action of aspirin

Answer 7

Inhibits thromboxane A2 production, which normally stimulates platelet aggregation and vasoconstriction

Question 8

What enzyme is responsible for clopidogrel metabolism into its active form?

Answer 8

CYP2C19

Question 9

Describe the binding of clopidogrel to its target and its action

Answer 9

Irreversibly inhibits P2Y12 SDP receptor

Blocks activation of GP IIb/IIIa pathway in platelet aggregation

Question 10

Name a DDI possibly associated with clopidogrel

Answer 10

PPIs - reduce effects of the drug, though evidence for this is poor

Question 11

Describe the mechanism of resistance to clopidogrel

Answer 11

14% of population have low CYP2C19 levels and show resistance
Lead to development of ticagrelor

Question 12

Describe the mechanism of action of fondaparinux

Answer 12

selective inhibitor of clotting factor Xa

Question 13

What is glycoprotein IIb/IIIa?

Answer 13

Integrin complex found on platelets which acts as a receptor for fibrinogen, aiding in platelet activation and clot formation

Question 14

What contraindications are associated with GP IIa/IIIa receptor inhibitors?

Answer 14

Bleeding

Thrombocytopenia (decreased platelets in blood)

Question 15

Describe some patients at risk of cariogenic shock

Answer 15

Age > 70 yo
HR > 110bpm
BP < 120mmHg

Question 16

Why are beta blockers being decreasingly used?

Answer 16

Thought to increase likelihood of cardiogenic shock

Question 17

When should beta blockers not be used?

Answer 17

At risk of cariogenic shock
Symptoms of coronary vasospasm
Cocaine use

Question 18

According to treatment SIGN 148, what should ACS be treated with immediately?

Answer 18

Aspirin and ticagrelor, followed by long term aspirin

Question 19

How long should patients with ACS undergo anti-platelet therapy following diagnosis?

Answer 19

at least 6 months

Question 20

What drugs are those with ACS put on for the long term?

Answer 20

Aspirin
Statins
ACEIs if they have unstable angina/ had an MI

Question 21

Who are put on ACEIs?

Answer 21

Those who have unstable angina
Have had an MI
Have signs of LV dynsfunction/HF

Question 22

What do those who have suffered an MI and have signs of left ventricular hypertrophy specifically get put on?

Answer 22

Eplerenone, K+ sparing diuretic