Cardiovascular

Question 1

What are the common indications for Calcium Channel Blockers?

Answer 1

HTN - 1st or 2nd line

• reduces risk of stroke, MI, and death from cardiovascular disease

Stable angina

• Symptom control

Supraventricular arrhythmias/tachycardia, atrial flutter, atrial fibrillation

• Controls cardiac rate

Question 2

Amlodipine and, to a lesser extent, nifedipine are used for the first- or second-line treatment of ______

What class of drugs are they?

Answer 2

HTN

CCBs

Question 3

Which CCBs are primarily used to control cardiac rate in ppl w/ supraventricular arrhythmias, including supraventricular tachycardia, atrial flutter and atrial fibrillation?

Answer 3

Diltiazem and verapamil

Question 4

What is the MOA of CCBs?

Answer 4

Decreased Ca concencentarstios w/ in cells

Question 5

What is the MOA of CCBs?

Answer 5

Decreased Ca concentrations w/ in cells, due to blocked entry in vascular + cardiac cells

Causing relaxation + vasodilation in arterial smooth muscle

Heart:

Dec myocardial contractility
+
Suppress cardiac conduction esp. @ AV node - dec ventricular rate
+
reduced after load
=

reduced myocardial oxygen demand hence preventing angina

Question 6

What are the 2 classes of CCBs?

Answer 6

Dihydropyridines - vasculature selective
(Amlodipine + nifedipine)

Non-dyhydropyridines - heart selective
(Verapamil + Diltiazem(also effects vasculature))

Question 7

Which CCB is the most cardio selective?

Answer 7

Verapamil

Question 8

List adverse effects of Amlodipine + Nifedipine + Diltiazem

Answer 8

Ankle swelling

flushing

headaches

Palpitations

Due to vasodilation + compensatory tachycardia

Question 9

List adverse effects of verapamil + Diltiazem

Answer 9

Constipation - common

Bradycardia

Heart block

Cardiac failure

Question 10

Which type of CCBs should not be prescribed w/ β-blockers except under close specialist supervision?

Answer 10

Non-dihydropyridine calcium channel blockers (verapamil and diltiazem)

Question 11

Prescribing verapamil/diltiazem in conjunction w/ β-blockers can result in what? (3)

Answer 11

Heat failure

Bradycardia

Asytole

Question 12

Verapamil and diltiazem should be used with caution in patients with _____

Answer 12

poor left ventricular function

AV nodal conduction delay

Question 13

Amlodipine and nifedipine should be avoided in patients with ________

Answer 13

Unstable angina

Severe aortic stenosis

Question 14

What are the 3 indications for loop diuretics?

Answer 14

1. Acute pulmonary oedema

Symptomatic relief of fluid overload;

2. Chronic heart failure
3. Other oedematous states -

(Renal disease/liver failure, may be given inconjunction w/ other diuretics)

Question 15

Loop diuretics should be used in conjunction w/ what 2 things to relieve breathlessness in acute pulmonary oedema?

Answer 15

Oxygen and nitrates

Question 16

Which part of the nephron do loops diuretics act on?

What is the MOA there?

Answer 16

Ascending limb of the loop of Henle

inhibit the Na+/K+/2Cl− co-transporter

Question 17

what does the inhibit the Na+/K+/2Cl− co-transporter protein do in the renal tubule?

Answer 17

transports sodium, potassium and chloride ions from the tubular lumen into the epithelial cell;

Water then follows by osmosis

Question 18

Name 2 loop diuretics

Answer 18

Furosemide

Bumetanide

Question 19

How do loop diuretics affect blood vessels?

How is this relevant in acute heat failure?

Answer 19

They dilate capacitance veins

Reduces preload and improves contractile function of the ‘overstretched’ heart muscle.

Question 20

Water loss in loop diuretics can lead to which 3 adverse effects?

Answer 20

Dehydration

Hypotension

Low electrolyte states

(i.e. hyponatraemia, hypokalaemia, hypochloraemia, hypocalcaemia, hypomagnesaemia and metabolic alkalosis).

Question 21

Why can high doses of loop diuretics cause hearing loss and tinnitus?

Answer 21

A similar Na+/K+/2Cl− co-transporter is responsible for regulating endolymph composition in the inner ear;

which gets affected at high doses

Question 22

Loop diuretics are contraindicated in pts w/ severe _____ +_______

Answer 22

dehydration

hypovolemia

Question 23

Loop diuretics should be used w/ caution in pts w/ which conditions?

Answer 23

Hepatic encephalopathy

Severe Hypokalaemia

Severe Hyponatraemia

Gout

Question 24

Why can loop diuretics worsen gout?

Answer 24

If taken chronically they can inhibit uric acid excretion and it can worsen the gout

Question 25

Why is loop diuretic use cautioned in ppl w/ hepatic encephalopathy?

Answer 25

The hypokalaemia can cause or worsen a coma

Question 26

Loop diuretics have the potential to affect drugs excreted where?

List some specific drugs (3)

Answer 26

Drugs that are excreted by the kidneys

Lithium

Digoxin (bc diuretic associated hypokalaemia)

Aminoglycosides (inc ototoxicity + nephrotoxicity)