Cardiovascular Pharmacology

Question 1

What does an inotrope do?

Answer 1

Agent that increases the force / energy if contractions

Question 2

What does a chronotrope do?

Answer 2

Agent that increases heart rate

Question 3

What does a dromotrope do?

Answer 3

Agent that increases conduction speed

Question 4

What is the pharmacodynamics of cardiac glycosides?

Answer 4

Inotrope, increases intracellular Ca.
Works by inhibiting the Na/K pump, therefore increasing intracellular Na. The 3Na/Ca exchanger NCX therefore stops moving Na in Ca out of the cell.
E.g. Digoxin

Question 5

What are the pharmacodynamics of loop diuretics?

Answer 5

Inhibit Na & Cl reabsorption from tubule in ascending loop of Henle.
Better than thiazide diuretics in pts with renal impairment.
E.g. Fursemide.

Question 6

What are the pharmacodynamics of thiazide diuretics?

Answer 6

Inhibit Na & Cl reabsorption from tubule in distal convoluted tubules.
Better than loop diuretics in pts with normal renal function.
E.g. Bendroflurazide

Question 7

What are the pharmacodynamics of potassium sparing diuretics?

Answer 7

Either inhibits Na reabsorption & K excretion in distal convoluted tubule or aldosterone antangonist.
E.g. Spirolactone (aldosterone antagonist - often weak so given with other diuretics)

Question 8

What is an adrenoceptor antagonist?

Answer 8

Block sympathetic neurotransmission.
E.g. Alpha & beta blockers.
Often used for HTN.

Question 9

What are the physiological effects of alpha I antagonists?

Answer 9

Arteriolar & venous vasodilation.

Question 10

What does a calcium channel blocker do?

Answer 10

Inhibit Ca influx in cardiac / smooth muscle contraction E.g. Diltiazem