Cardiovascular Disease

Question 1

What are the two determinants of blood pressure?

Answer 1

TPR and CO

Question 2

What sort of drug is bendraflumethiazide and how does it act to lower blood pressure?

Answer 2

Thiazide diuretic –> acts on DCT
inhibits Na/Cl transporter –> causes increase in intracellular calcium
some direct effect on vascular smooth muscle
mechanism changes over time

Question 3

What class of drug is ramipril?

Answer 3

ACE inhibitor

Question 4

What would you prescribe for someone with atrial fibrillation, tachycardia, dyspnoea and ankle oedema?

Answer 4

Digoxin –> anti-arrhythmic + reduces tachycardia

Warfarin –> prevents blood clots

Question 5

What is the mechanism of action of warfarin?

Answer 5

inhibits vitamin K dependent conversion of glutamate to G-carboxyglutamate which is important in a number of clotting factors.
Reductase enzyme in the liver activates vitamin K to its hydroquinone form which activates clotting factors 2,7,9,10

Question 6

How do digoxin and other cardiac glycosides work?

Answer 6

they inhibit the Na/K pump –> increased accumulation of intracellular Na+ –> increased intracellular Ca2+ via Na+/Ca2+ exchange = POSITIVE INOTROPIC EFFECT
binds to K+ channel
some evidence that CGs also stimulate the parasympathetic NS

Question 7

What might chest pain following exertion be caused by?

Answer 7

angina pectoris –> stable inadequate blood flow in the coronary vessels –> leads to buil up of adenosine, hydrogen + can stimulate pain receptors

Question 8

How do you treat angina pectoris?

Answer 8

sublingual GTN spray –> stops 1st pass metabolism

Question 9

What three drugs might you prescribe to someone with very high cholesterol + how do they act?

Answer 9

simvastatin –> blocks HMG-CoA reductase –> decreases cholesterol production
bisoprolol –> beta blocker –> reduces HR –> reduces myocardial demand
aspirin –> blocks COX1 –> stops TXA2 production which aids platelet aggregation usually (suicide inhibitor)

Question 10

What is congestive heart failure?

Answer 10

inefficient CO required for body oxygen demands

Question 11

How do you treat congestive heart failure?

Answer 11

Furosemide –> potent diuretic that has its effects in the ascending limb of the loop of Henle
Peridopril –> ACE inhibitor
Propranolol –> ONLY GIVEN SOME MONTHS LATER –> beta blocker = could impair cardiac contractility