Cardio Flashcards
(112 cards)
0
Q
Mode of action of furosemide
A
Short acting, within an hour, diuresis takes 6 hrs
- acts on the ascending loop of henle to inhibit Na/K/2Cl pump causing inhibition of Na K and water reabsorption, leading to an increased loss of salt, water K
- blood becomes hypovolaemic, reducing BP
1
Q
Drug class of furosemide
A
Loop diuretic
2
Q
Indications for furosemide
A
- pulmonary oedema (secondary to left ventricular failure)
- chronic HF - oedema
- oliguria secondary to renal failure
- resistant hypertension
3
Q
Contraindications of furosemide
A
Hypovolaemia
Dehydration
Hyponatraemia (severe)
Comatose States (associated with liver cirrhosis)
4
Q
Side effects of furosemide
A
Mild GI disturbances
Hypotension
Hyperglycaemia
Electrolyte disturbance
5
Q
Which type of diuretic, loop or thiazide, is more likely to cause hyperglycaemia as a side effect ?
A
Thiazide
6
Q
When May a particularly high dose of furosemide be required ?
A
In renal impairment - may cause deafness as a side effect
7
Q
What are the possible interactions of furosemide ?
A
Antibacterials: increased risk of ototoxicity with amino glycosides, colistin, vancomycin
Digoxin: furosemide-induced hypokalaemia with digoxin causes arrhythmias
8
Q
What class of drug is bendoflumethiazide
A
Thiazide diuretic
9
Q
How do thiazide diuretics work ?
A
Inhibit sodium reabsorption at the beginning of the distal convoluted tubule
- act within 1to 2 hrs
- diuresis usually takes 12 to 24 hrs, usually given early in day so doesn’t interfere with sleep
10
Q
Indications for bendoflumethiazide
A
Oedema
Hypertension (alone in mild or combo in severe)
Mild to moderate HF
11
Q
Contraindications of bendoflumethiazide
A
- (Refractory) hypokalaemia, hyponatraemia, hypercalcaemia
- (symptomatic) hyperuricaemia
- Addison’s disease (primary adrenal insufficiency)
- caution with: gout, diabetes, SLE
12
Q
Side effects of bendroflumethiazide
A
GI disturbances Postural hypotension Altered plasma/lipid concentrations Metabolic/electrolyte disturbances Gout
13
Q
Possible interactions of bendroflumethiazide
A
Digoxin: hypokalaemia caused by diuretic with digoxin can cause dysthymia
Lithium: increases excretion further causing inc plasma conc and inc risk of toxicity
14
Q
What drug class is spironalactone
A
Potassium sparing diuretic
15
Q
How does spironalactone work ?
A
Acts on receptors in distal Tubule: competitive inhibition if aldosterone
Inhibits Na retention; increased Na excretion
(Often given in combo with another diuretic instead of potassium supplements)
16
Q
Indications for spironalactone
A
Oedema Ascites (cirrhosis of liver, malignant) Nephrotic syndrome Congestive heart failure Primary hyperaldosteronism (conn syndrome)
17
Q
Contraindications of spironalactone
A
Hyperkalaemia
Hyponatraemia
Anuria
Addison’s disease (primary adrenal insufficiency)
18
Q
Side effects of Spironolactone ?
A
GI disturbances Impotence Gynaecomastia Menstrual irregularities Lethargy/headache/confusion
19
Q
Possible. Interactions of Spironolactone
A
Can increase blood levels of other drugs due to hypovolaemia, therefore increasing their potency
20
Q
Why a class of drug is atenolol?
A
Beta blocker
21
Q
How do beta blockers work ?
For hypertension, anti-arrhythmic, angina
A
Acts on beta 1 receptors in the heart (peripheral vasculature, bronchi, pancreas and liver)
- Decreases HR and force of contraction therefore decreasing workload of the heart
- reduced renin production from kidneys = anti-hypertensive
- reduced conduction/AP initiation of heart = anti-arrhythmic
22
Q
Indications for atenolol
A
Hypertension Angina Supra ventricular dysrhymias MI prophylaxis Migraine prophylaxis
23
Q
Contraindications for atenolol
A
Asthma HF 2nd/3rd degree heart block Bradycardia COPD
24
Side effects of atenolol?
```
Lethargy
Bradycardia
Cold extremities
AV block
Sleep disturbance/nightmares
```
25
Which beta blockers are less likely to cause nightmares as a side effect ?
Those that are water soluble e.g. Atenolol, celiprolol, nadolol, sotalol
- less likely to to enter brain
26
Possible interactions of atenolol
Verapamil: increased risk of HF/bradycardia/AV block
Insulin: masks symptoms of hypoglycaemia
Diltiazem: (ca channel blocker) increased risk of bradycardia/AV block
27
What drug class is diltiazem ?
Calcium channel blocker
28
How do calcium channel blockers work ?
Inhibit Ca influx into vascular smooth muscle and myocardium by inhibiting L-type Ca channel
Causing relaxation of vascular smooth muscle which results in:
- decreased myocardial contractility
- decreased conduction at AV node (inc refractory period)
- decreased after load and HR meaning decreased oxygen consumption
29
Which calcium channel blockers should usually be avoided in heart failure and why ?
They may further depress cardiac function and cause significant clinical deterioration
Can use dihydropyridine ca channel blockers instead e.g. Amlodipine etc which have more effect on the vessels and less on the myocardium
30
Indications for diltiazem
Angina (prophylaxis and treatment)
Hypertension (longer acting formulation used)
* may be used in patients who are contraindicated to beta blockers or ineffective*
31
Contraindications of diltiazem
Severe bradycardia
Heart failure
2nd/3rd degree heart block
Pregnancy/breastfeeding
32
Side effects of diltiazem
Headache, nausea, dizziness, hypotension, bradycardia, ankle swelling
33
Possible interactions of diltiazem
Antiarrythmics: cause increased myocardial depression
Beta blockers: increased risk of AV block/bradycardia
Causes increased plasma conc of cyclosporins and digoxin
34
What class of drug is ramipril ?
Ace inhibitor
35
How do ace inhibitors work ?
Inhibits angiotensin converting enzyme, causing:
- decreased angiotensin 2 synthesis = decreased peripheral resistance/fluid overload
- increased bradykinin = peripheral vasodilation
36
Indications for ramipril ?
Hypertension
Heart failure
Post-MI
Diabetic neuropathy
37
Which medications should be stopped before starting an ACE inhibitor for treatment of HF in order to avoid hyperkalaemia?
Potassium supplements and potassium sparing diuretics
*note: low dose Spironolactone in severe HF may be beneficial if serum potassium levels monitored carefully *
38
An ACE Inhibitor may be most appropriate initial drug for hypertension in which patients ?
Younger Caucasian
*Respond less well:*
Afro Caribbean
Aged over 55
Primary aldosteronism
39
Why are ACE inhibitors particularly indicated for hypertension in patients with type 1 diabetes with nephropathy ?
ACE inhibitors potentate the hypoglycaemic effect of insulin and oral antidiabetic drugs
40
Contraindications of ramipril
```
Renovascular disease
Aortic stenosis
Pregnancy
Acute porphyria
Angioedema
```
41
Common side effects of ramipril ?
Postural hypertension
Dry cough
Renal impairment
GI & other upper resp
42
Possible interactions of ramipril ?
Diuretics = pronounced hypotension
K- sparing diuretic = inc risk hyperkalaemia
Lithium & NSAIDs = inc plasma conc
NSAID also risk of renal damage
43
What class of drug is losartan ?
Angiotensin 2 receptor antagonist
44
In what way are AT2 blockers different to ACE inhibitors ?
Do not inhibit the breakdown of bradykinin- therefore unlike,y to cause persistent dry cough
45
Indications for losartan ?
```
Hypertension
Chronic HF (when ACEi unsuitable)
Diabetic nephropathy in type 2 diabetes
```
46
Contraindications of losartan
```
Pregnancy/breastfeeding
Caution with:
Renal artery stenosis
Aortic or mitral valve stenosis
Hepatic or renal impairment
```
47
Possible interactions of losartan
Antibacterials: plasma conc of losartan its active metabolite reduced by rifampicin
48
Side effects of losartan
Hypotension/ dizziness
Hyperkalaemia occasionally
*usually very MILD*
49
How do cardiac glycoside drugs work ?
Reduce conductivity within AV Node
- increased AV refractory period -> decreased HR
Increase force of contraction of myocardium
- inhibits Na/K pump causing increased intracellular conc of Na which in inhibits Na/Ca pump -> less Ca pumped out, increased intracellular Ca -> increased force of contraction
50
What is the most commonly used cardiac glycoside ?
Digoxin
51
Why is digoxin rarely used for rapid control of heart rate ?
Even with IV admin response may take hours
52
For what are cardiac glycosides most useful for ?
Controlling ventricular response in atrial fibrillation and flutter
53
What electrolyte disturbance predisposes to digitalis toxicity in patient taking digoxin ?
Hypokalaemia
54
Indications for digoxin
Supraventricular arrhythmias - Atrial fibrillation and flutter
HF (sinus rhythm, unresponsive to ACE inhibitors, b blocker and diuretic)
55
What is the effect of digoxin on heart failure ?
| - how affects symptoms, exacerbation, mortality
Improves symptoms and exercise tolerance
Reduces hospitalisation due to acute exacerbations
Does not reduce mortality
56
Contraindications of digoxin
Complete heart block
Wolff-Parkinson-white syndrome
Ventricular tachycardia or fibrillation
Hypertrophic cardiomyopathy
57
Possible interactions of digoxin
Increased risk of digoxin toxicity with:
Antiarrythmics: Amiodarone, propafenone, quinidine
Ca channel blockers
Diuretics
58
Side effects of digoxin
Nausea, vomiting, anorexia, diarrhoea
| Visual disturbances
59
What class of drug is isosorbide mononitrate ?
Nitrate
60
How do nitrates work?
Metabolised to NO in smooth muscle cells causing activation of guanylyl cyclise, which causes vascular smooth muscle relaxation resulting in vasodilation of coronary arteries and systemic veins = decreased preload and increased oxygen supply to myocardium
+ reduction in venous return reducing left ventricular work
61
Indications for isosorbide mononitrate
Angina prophylaxis
| Congestive heart failure
62
Contraindications of isosorbide mononitrate
Hypotension/hypovolaemia
Hypertrophic cardiomyopathy
Aortic/mitral stenosis
63
Side effects of isosorbide mononitrate ?
Headache, dizziness, postural hypertension, flushing, tachycardia
64
Interactions of isosorbide mononitrate
Sildenafil (Viagra): increased hypotensive effects
65
How can nitrate tolerance be avoided when taking isosorbide mononitrate ?
Drug free periods of 8 hours
66
How do beta blockers act as anti arrhythmics?
By attenuating the effects of sympathetic nervous system on automaticity and conductivity within the heart
67
What class of drug is amiodarone ?
(Class III) anti arrhythmic
68
What is the mechanism of action of amiodarone ?
Block K+ channels, slowing cell depolarisation and increasing refractory period; also blocks Na, Ca channels and beta receptors
69
Indications for amiodarone
Ventricular fibrillation
Haemodynamically unstable ventricular tachycardia
Wolff-Parkinson-White tachyarrhythmias
70
Contraindications of amiodarone ?
Severe sinus node dysfunction causing bradycardia
2nd/3rd degree heart block
Hepatitis
Thyroid dysfunction
71
What function tests should be monitored before treatment with amiodarone and then every 6 months ?
Liver and thyroid function
72
Side effects of amiodarone
```
Arrhythmia
Nausea/vomiting
Skin discolouration
Vision disturbances
Photo sensitivity
Thyroid disorders
Hepatotoxicity
```
73
Possible Interactions of amiodarone
B blockers and diltiazem /verapamil: increased risk of bradycardia, AV block and myocardial depression
Digoxin and phenytoin: increased risk of toxicity
Warfarin: inhibits warfarin metabolism, increased risk of bleeding
74
What drug class is aspirin ?
Anti platelet/salicylate
75
Mechanism of action of aspirin ?
```
Inhibits cyclooxygenase (COX) enzymes;
Anti platelet actions due to irreversible acetylation of COX1 in platelet preventing their activation
```
76
Indications of aspirin
Acute MI & primary/secondary prophylaxis
Secondary prophylaxis of cerebrovascular events
Analgesic, antipyretic, anti inflammatory
77
Contraindications of aspirin
Active peptic ulcer
Bleeding disorders
NSAID/aspirin hypersensitivity
Breast feeding (Reyes syndrome)
Caution with:asthma, third trimester of pregnancy
*not to be given <16yrs unless for anti-platelet*
78
Elimination of aspirin hepatic or renal ?
Renal
79
Side effects of aspirin ?
Dyspepsia
Urticaria
Bronchospasm
GI bleeding/ulceration
80
What drug class is clopidogrel ?
Anti platelet: adenosine diphosphate (ADP) receptor blocker
81
Mechanism of action of clopidogrel ?
Inhibits platelet activation by blocking the actions of ADP on P2Y12 (subtype of ADP receptor) which inhibits eventual cross linking by fibrin (aggregation)
82
Indications for clopidogrel
Prevention of atherosclerotic events in PAD + STEMI
| Post MI/Ischaemic stroke
83
Contraindications of clopidogrel
Active bleeding
Severe hepatic impairment (bleeding risk)
Pregnancy and breastfeeding
84
Side effects of clopidogrel ?
Diarrhoea, dyspepsia, abdo pain
Rash
Haemorrhage
85
Possible interactions of clopidogrel ?
NSAIDS and aspirin increase risk of bleeding
86
What class of drug is streptokinase ?
Thrombolytic
87
How do Thrombolytic drugs work ?
Promote conversion of plasminogen to plasmin. Plasmin is a proteolytic enzyme which dissolves the clots
88
Indications for streptokinase ?
- Acute MI (within 12hrs, preferably within 1) - biggest benefit in this with STEMI (anterior infarct) and bundle branch block
- DVT
- PE
- acute arterial thromboembolism
- central retinal venous or arterial thrombosis
89
Contraindications of streptokinase
Recent haemorrhage, trauma, surgery
Coagulation defects, bleeding conditions, aortic dissection, aneurysm
*anything that will increase risk of bleeding*
90
Side effects of streptokinase
```
Nausea/vomiting
Bleeding
Reperfusion arrhythmias, recurrent Ischaemia, angina (MI), cerebral oedema
Hypotension
Fever
```
91
Interactions of streptokinase
Activated by liver enzyme cytochrome p450:
| Decreased warfarin metabolism, more in blood, increased risk of bleeding
92
What drug class is enoxaparin
Heparin (LMWH)
93
Why are low molecular weight heparins usual,y preferred over unfractionated heparin in the prevention of venous thromboembolism ?
As LMWHs are equally as effective with less risk if heparin induced thrombocytopenia
Also don't require monitoring and have longer duration if action so can use once daily for convenience
94
Indications for enoxaparin
```
PE
DVT
Prophylaxis of thromboembolic disorders
Unstable angina
STEMI and non-Q-wave MI
```
95
Contraindications of enoxaparin
```
Active bleeding
Neonates
Severe liver disease
Peptic ulcer
Bacterial endocarditis
```
96
Side effects of enoxaparin ?
Haemorrhage
Thrombocytopenia
Elevated liver aminotransferases
97
Possible interactions of enoxaparin
Aspirin increased risk of bleeding
98
What is the main route of elimination of enoxaparin ?
Renal
99
What drug class is warfarin ?
Vitamin k antagonist (anticoagulant)
100
Mechanism of action of warfarin ?
Prevents activation of vitamin k, a key cofactors in the coagulation cascade, therefore inhibiting coagulation
Clotting factors 2,7,9&10 dependent on vit k
101
Indications of warfarin ?
Prophylaxis of embolisation in rheumatic heart disease and AF
Prophylaxis after prosthetic heart valves
Prophylaxis after treatment of PE and venous thrombosis
TIA
102
Contraindications of warfarin
Peptic ulcer
Severe hypotension
Pregnancy (1st and 3rd trimester) & avoid breastfeeding
Severe Renal or kidney disease
103
Main route of elimination for warfarin ?
Liver
104
Side effects of warfarin
Haemorrhage
Headache
Nausea/vomiting/diarrhoea
Purple toe syndrome
105
Possible interactions of warfarin
Amiodarone : increases effect of warfarin by inhibiting metabolism (cyt P450)
Cranberry juice: increased anticoagulant effect
106
How do statins work ?
Competitively inhibit HMG CoA-Reductase, the key enzyme in cholesterol synthesis, therefore reducing cholesterol production
107
Indications for simvastatin
Hypercholesterolaemia/hyperlipidaemia
| Prophylaxis of CV events in those with atherosclerotic disease/diabetes
108
Contraindications of simvastatin
Active liver disease
| Pregnancy/breast feeding
109
Side effects of simvastatin
Myositis -> rhabdomyolysis (rare but significant)
GI disturbances
Rarely pancreatitis, anaemia
110
Possible interactions of warfarin
Cyclosporins and fibrates: increased risk of myositis
| Warfarin: increased effects of warfarin
111
Elimination of warfarin
Liver
