Cardiovascular

Question 1

Bisoprolol / Atenolol: mechanism of action

Answer 1

Cardioselective beta-blockers
Block beta-1 receptors in cardiac (and renal) tissue to inhibit sympathetic stimulation of cardiac/renal vasculature
Blockade of sino-atrial node (HR drops) and myocardium receptors (contractility decreases)
Blockade of beta-1 receptors in kidneys inhibits renin release, depressing vasoconstriction caused by RAAS

Question 2

Bisprolol / Atenolol: indications

Answer 2

Hypertension
Angina
Rate-control in AF

Question 3

Bisoprolol / Atenolol: contra-indications

Answer 3

Asthma (bronchospasm)
History of hypoglycaemia
Not to be co-prescribed with CCB (risk of heart block)

Question 4

Propranolol / Carvedilol: mechanism of action

Answer 4

Non-cardioselective beta-blockers
Propranolol = anti-beta 1
Carvedilol = anti-beta 1, anti-beta 2 and anti-alpha 1

Question 5

Propranolol / Carvedilol: indications

Answer 5

Hypertension
Angina
Anxiety
Migrane prophylaxis
Post-MI prophylaxis

Question 6

Propranolol / Carvedilol: adverse effects

Answer 6

Fatigue (10%)
Cold extremities
Bradycardia
Hypotension
Bronchospasm

Question 7

Ramipril / Enalapril: mechanism of action

Answer 7

ACE-inhibitors
Inhibits conversion of angiotensin I to II, preventing vasoconstriction and aldosterone release
This depresses renal Na and fluid retention, so decreases blood volume

Question 8

Ramipril / Enalapril: indications

Answer 8

Hypertension
HF
Nephropathy
Prevention of cardiac events in high risk patients

Question 9

Ramipril / Enalapril: adverse effects

Answer 9

Dry cough (10%)
Hypotension
Hyperkalaemia
Renal impairment
Angioedema

Question 10

Isosorbide mononitrate / Glyceryl trinitrate (GTN): mechanism of action

Answer 10

Nitrate drugs
Drug is converted to nitric oxide (NO) - a potent vasodilator that acts mostly on coronary blood vessels to enhance flow to ischaemic areas of myocardium
Used in angina

Question 11

Verapamil / Diltiazem: mechanism of action

Answer 11

Rate-limiting CCB
Block L-type calcium channels to prevent Ca2+ entry to cells - decreases contractility of myocardial and smooth muscle
Heart contractility decreases
Coronary blood vessels dilate
HR decreases - antidysrhythmic actions due to prolonged AV node conduction

Question 12

Verapamil / Diltiazem: mechanism of action

Answer 12

Supraventricular arrhythmias
Angina
Hypertension

Question 13

Verapamil / Diltiazem: contra-indications

Answer 13

Heart failure

Left ventricular dysfunction

Question 14

Amlodipine / Nifedipine / Felodipine: mechanism of action

Answer 14

Non rate-limiting CCB

Same as Verapamil / Diltiazem but do NOT lower heart rate

Question 15

Amlodipine / Nifedipine / Felodipine: indications

Answer 15

Hypertension

Angina

Question 16

Simvastatin / Atorvastatin: mechanism of action

Answer 16

HMG CoA reductase inhibitors
Competitively inhibits HMG CoA reductase, which increases LDL-receptor expression on hepatocytes
This increases hepatic uptake of cholesterol to lower plasma cholesterol to reduce atherosclerotic plaques

Question 17

Simvastatin / Atorvastatin: indications

Answer 17

Prevent cardiac events in high risk patients

Familial hypercholesterolaemia

Question 18

Digoxin: mechanism of action

Answer 18

Cardiac glycoside
Increases force of contraction (inotrope) and reduced rate of conduction through AV node
Does this by increasing vagal parasympathetic activity to create buildup of Ca2+ in cardiac cells

Question 19

Digoxin: indications

Answer 19

Heart failure

Rate control in AF

Question 20

Amiodarone: mechanism of action

Answer 20

Anti-arrhythmic drug

Restores regular sinus rhythm by blocking cardiac K+ channels to prolong repolarisation of the AP

Question 21

Amiodarone: adverse effects

Answer 21

Hypersensitivity and skin reactions - need to avoid sun exposure