Cardio pharma Flashcards
Vaughn Williams 1a
Quinidine - delays
Ventricular dysrhythmias, AF
Vaughn Williams 1b
Lidocaine - aborts premature beats
VT and VF
Vaughn Williams 1c
Flecainide
(Not specific to damage cells;
suppresses re-entrant rhythms)
Paroxysmal AF; recurrent tachy’s (WPW)
Vaughn Williams 2
Beta blocker
Mi, Tachycardia
Vaughn Williams 3
K+ Channel Blockers
e.g. Amiodarone
(Prolong repolarisation)
SVT (WPW)
Vaughn Williams 4
Calcium Channel Blockers
e.g. Verapamil; Diltiazem
SVT; reduce rate in
AF (SA & AV node)
Beta blockers example
Bisoprolol; Atenolol; Propanolol.
Beta blockers mechanism
Negatively inotrophic & chronotrophic.
Beta blockers indication
hypertension; angina pectoris; following
MI; cardiac dysrhythmias (e.g. AF).
Beta blockers side effect
GI disturbances; bradycardia; fatigue;
cold peripheries; heart failure; hypotension; dizziness;
sexual dysfunction; peripheral vasoconstriction;
bronchospasm.
Beta blockers CI
asthma; marked bradycardia;
heart block; uncontrolled heart failure; PVD;
Prinzmetal’s angina; hypotension; cardiogenic shock.
Note: β - Blockers should not be used in conjunction with verapamil
and diltiazem (non-dihydropyridines) in HF because of their additive
effects (↓HR, contractility, CO).
Non-dihydropyridines
Verapamil & Diltiazem Negatively inotrophic / chronotrophic but DO NOT USE IN HEART FAILURE • Indications: o Verapamil: fast AF, SVT, hypertension.
Dihydropyridines
Amlodipine, Felodipine, Nifedipine
Dilates peripheral arteries, ↓ after-load, dilates
coronary vessels, act on vessels > myocardium
CCB Indications:
o Verapamil: fast AF, SVT, hypertension.
o Dihydropyridines: hypertension; to prevent
angina.
CCB ADRs
• Side effects:
o Verapamil & Diltiazem: constipation; N&V;
flushing, headache, dizziness; fatigue.
o Dihydropyridines: abdominal pain; nausea;
palpitations, flushing, oedema; headache;
dizziness; sleep disturbances; fatigue.
CCB CIs
• Contraindications:
o Verapamil & Diltiazem: HF, 2nd or 3rd degree
heart block, cardiogenic shock.
o Dihydropyridines: Unstable angina, significant
AS.
Nitrates
Examples: Isosorbide Mononitrate (PO); GTN infusion
(IV); GTN spray (S/L).
• Indications: stable angina (prevention + treatment);
unstable angina (IV); acute heart failure (IV); chronic
HF.
Nitrate CIs
Contraindications: hypersensitivity to nitrates;
hypotensive conditions; hypovolaemia; hypertrophic
obstructive cardiomyopathy; AS; MS; cardiac
tamponade; constrictive pericarditis; marked anaemia.
Nitrate ADRs
Side effects: postural hypotension; tachycardia;
throbbing headache; dizziness.
o TOLERANCE
Ace inhibitors examples
ACE inhibitors
• Examples: Ramipril; Lisinopril; Enalapril.
ACE inhibitors mechansism
Inhibits conversion of angiotensin 1 into
angiotensin 2, therefore inhibiting angiotensin 2 having
its effects:
o Increasing sympathetic activity.
o Fluid retention by kidney – via Increase in
aldosterone and direct action.
o Arteriolar vasoconstriction.
o Stimulating ADH secretion causing increased
fluid retention.
ACE inhibitors also cause:
o Reversal of left ventricular hypertrophy.
o Reversal of endothelial dysfunction.
ACEi indications
Indications: hypertension; HF; following MI
(especially ventricular dysfunction); IHD risk; diabetic
nephropathy; progressive renal insufficiency.
ACEi ADRs
Side effects: renal impairment; persistent dry cough;
angioedema; rash; hypotension; pancreatitis;
hyperkalaemia; GI effects.
ACEi CIs
Contraindications: hypersensitivity to ACEi
(angioedema); renal artery stenosis; pregnancy; aortic
stenosis; toxicity.
Loop diuretics
Loop diuretics
• Examples: Furosemide, Bumetanide.
• Action: Blocks Na+/K+/Cl- co-transporter in the apical
membrane of the thick ascending limb of loop of
Henle.
Loop indications
• Indications: hypertension; water overload: pulmonary
oedema in LVF, chronic HF, nephrotic syndrome, renal
failure.
Loop ADRs
Side effects: hypokalaemia; metabolic alkalosis;
sodium & magnesium depletion; hypovolaemia &
hypotension; deafness; nausea; allergies.
Thiazides
Examples: Bendroflumethiazide.
• Action: Inhibits Na+ reabsorption at the beginning of
the distal convoluted tubule. Blocks Na+/Cl- symporter
that is associated with the luminal membrane.
• Side effects: postural hypotension; hypokalaemia;
hypomagnesaemia; hyponatraemia; hypercalcaemia;
metabolic alkalosis; hyperuricaemia; impotence;
hyperglycaemia.
Thiazide indications
• Indications: hypertension; severe resistant oedema;
HF.
Thiazide side effects
• Side effects: postural hypotension; hypokalaemia;
hypomagnesaemia; hyponatraemia; hypercalcaemia;
metabolic alkalosis; hyperuricaemia; impotence;
hyperglycaemia.
Thiazide CIs
• Contraindications: refractory hypokalaemia;
hyponatraemia; hypercalcaemia; symptomatic
hyperuricaemia; Addison’s disease.
Potassium sparing
K+ Sparing Diuretics
• Examples: Spironolactone; Amiloride.
• Action: Act on collecting tubules. Spironolactone is
an aldosterone antagonist. Other potassium sparing
diuretics act by directly inhibiting sodium channels e.g.
Amiloride.
• Indications: co-use with K+ losing diuretics; CCF;
cirrhosis; oedema.
Potassium sparing ADRs
• Side effects: GI disturbances; impotence;
gynaecomastia; menstrual irregularities; lethargy;
headache; confusion; hyperkalaemia; hyponatraemia;
hepatotoxicity.
Lipid lowering drugs
Main indications: o Secondary prevention of MI and stroke. o Primary prevention arterial disease (raised serum Cholesterol). o Dyslipidaemias. • Main drug classes: o Statins o Fibrates o Ezetimibe
Statins
• Examples: Atorvastatin; Simvastatin.
• Action: Lowers cholesterol levels in blood by:
o Blocking liver enzyme hydroxy-methylglutarylcoenzyme
A reductase (HMG-CoA reductase),
thereby inhibiting liver synthesis of cholesterol.
o This leads to upregulation of expression of LDL
receptors on liver cells causing ↑ absorption of
LDL from the circulation.
Statin CIs and ADRS
Side effects: myositis; rhabdomyolysis; headache;
altered LFTs; paraesthesia; GI effects.
• Contraindications: active liver disease; pregnancy;
breast-feeding.
Other lipid lowering drugs
Fibrates
• Lower triglycerides more than LDL.
Ezetimibe
• ↓ Cholesterol absorption in the intestine.
Note: Risks of rhabdomyolysis increases with combination lipid lowering treatment. NEVER co-prescribe GEMFIBROZIL (a fibrate) and a STATIN.
Antiplatelet indications
Main indications relate to arterial thrombosis:
acute MI; CABG; unstable angina; coronary artery
angioplasty / stenting; cerebrovascular disease; AF.
Aspirin
• Suppresses production of prostaglandins and
thromboxane by irreversibly inactivating the
cyclooxygenase (COX) enzyme.
• Irreversibly blocks the formation of thromboxane A2 in
platelets, inhibiting platelet aggregation.
Clopidogrel
Inhibits ADP-induced aggregation through an active
metabolite.
• STEMI / NSTEMI given with aspirin.
Dipyrimadole
• Phosphodiesterase inhibitor. May be given in addition
to aspirin in those with a history of recurrent
cerebrovascular disease.
Glycoprotein IIA/ IIIB receptor antagonists
• Example: Abciximab.
Heparin mechanisms
• UHF:
o Binds to Antithrombin III (ATIII).
o ATIII is an endogenous inhibitor of coagulation.
o Increases ATIII ability to inhibit factors IXa, Xa,
XIa, XIIa (serine proteases) and thrombin
(unfractionated).
o UHF fully reversible with Protamine.
• LMWH:
o Inhibits factor Xa but not thrombin.
o LMWH not fully reversible with Protamine.
Heparin indications
• Main indications: acutely for short-term anticoagulation: DVT; PE; AF; prosthetic heart valves; cardiac events (unstable).
Heparin side effects and CIs
• Side effects: haemorrhage.
• Contraindications: uncontrolled bleeding / risk of
bleeding e.g. peptic ulcer, recent cerebral
haemorrhage; endocarditis.
Warfarin
• A coumarin
• Action: Inhibits vitamin K dependent clotting factors
(II, VII, IX, X, protein C & S). Does this through
inhibiting the reductase enzyme responsible for the
regeneration of the active form of vitamin K.
Warfarin indications
• Indications: long-term anticoagulation: DVT; PE; AF;
prosthetic heart valves; cardiac events (unstable).
Warfarin ADRs and CIs
• Side effects: haemorrhage.
• Contraindications: peptic ulcer; severe
hypertension; bacterial endocarditis; pregnancy.
Warfarin OD
• Overdose: INR <6: Decrease / omit Warfarin INR 6-8: Stop Warfarin. Restart when INR<5 INR >8: If no bleeding stop Warfarin & give 0.5- 2.5mg vitamin K if risk of bleeding.
Managing a major bleed on warfarin
• Major bleed: Stop Warfarin. Give prothrombin
complex concentrate (Beriplex) contains factors II, VII,
IX, X or FFP. Give 5mg vitamin K. Get HELP!
