Cardiovascular System Flashcards
Loop Diuretics
Furosemide, Bumetanide
Mechanism of Action
Act on ascending loop of Henle as Na/K/2Cl co-transporter inhibitors to reduce reabsorption of Na/K and therefore water
Loop Diuretics
Indications
Acutely - pulmonary oedema, hyperkalaemia
Long term - oedematous states such as CHF, renal failure, liver failure
Loop Diuretics
Contraindications
Hypovolaemia/dehydration
Hepatic encephalopathy, hypokalaemia, hyponatraemia, gout (may inhibit uric acid secretion), may exacerbate DM
Loop Diuretics
Side Effects
Hypotension
Low electrolytes, Hearing loss/tinnitus at high doses
Loop Diuretics
Interactions
Affects renal secretion, increased risk of digoxin toxicity due to hypokalaemia and ototoxicity/nephrotoxicity of other drugs increased
Thiazide-type diuretics
Names
Hydrochlorothiazide, Bendroflumethiazide, Indapamide, Chlortalidone
Thiazide-type diuretics
Mechanism of Action
Inhibit Na/Cl cotransporter in distal convoluted tubule to prevent absorption of water
Thiazide-type diuretics
Indications
Second line for hypertension treatment
Thiazide-type diuretics
Contraindications
Low K+/Na+, gout
Thiazide-type diuretics
Side effects
Hyponatraemia, risk of low potassium/increased glucose
Thiazide-type diuretics
Interactions
Other potassium lowering drugs
Thiazide-type diuretics
Prescription Advice
Give am to avoid nocturia, work wel with ACEi/AIIRB as work on opposing limbs of RAAS and K homeostasis
K+ Sparing Diuretics (Combo)
Names
Spironolactone, Amiloride (Co-amulifrose/co-amilozide)
K+ Sparing Diuretics
Mechanism of Action
Antagonist of aldosterone or act at ENaCs at DCT to reduce loss of K+
K+ Sparing Diuretics
Indications
Combination therapy if patient is hypokalaemic due to loop/thiazide therapy, ascitic, or hypertensive
K+ Sparing Diuretics
Contraindications
Renal imparment, hyperkalaemia, increasing hypokalaemia, rising volume depletion
K+ Sparing Diuretics
Side effects
hepatotoxicity, malaise, dizziness, gynaecomastia, breast pain, menstrual changes (spiro alters metabolism of testosterone in peripheral circulation)
K+ Sparing Diuretics
Interaction
Potassium supplements, renal clearance drugs (digoxin, lithium)
Beta-Blockers
Mechanism of Action
Anagonist of Beta-1 adrenoreceptors which gives negatively inotropic/chronotropic effect to reduce O2 demand and improve perfusion, reduces renin secretion, prolongs refractory period at AV node
Beta-Blockers
Indications
IHD, CHF, AF, SVT, HTN
Beta-Blockers
Contraindications
Asthma (bronchospasm), COPD (although not propranolol), haemodynamic instability, heart block, hepatic failure/heart failure require low dose
Beta-Blockers
Side effects
Fatigue, cold extremities, headache, GI change, sleep disturbance, impotence
Beta-Blockers
Interactions
Non-dihydro CCBs (verapamil/dilitiazem) - together can cause heart block, bradycardia, asystole
Calcium Channel Blockers
Mechanism of Action
Reduce Ca entry into vascular/cardio-myocytes to reduce contractility, reduce AV conduction to slow ventricular rate and decrease afterload - overall reduces O2 demand of heart
CCBs - Indications
Antihypertensives (dihydros)
Rhythm control drugs (SVT, AF, AFl, non-dihydros)
CCBs - contraindications
Poor LV function, AV nodal conduction delay, unstable angina and severe aortic stenosis (dihydros)
CCBs - Side effects
Dihydros - ankle oedema, flush, headache, palpitations
Verapamil - constipation, bradycardia, heart block, cardiac failure
Diltiazem - both
CCBs - interactions
Beta-blockers - negatively chronotopic and inotropic
CCBs - Dihydro vs non-dihydropytidine
Dihydro = -dipine (amlodipine, nifedipine) Non-D = Verapamil and Diltiazem (verapamil most cardioselective)
ACE-inhibitors
Names
Rampiril, Lisinopril, Perindopril
ACE-inhibitors
Mechanism of Action
Prevent conversion of AT1–>AT2. AT2 is a vasoconstrictor and stimulates aldosterone/ADH therefore afterload is reduced with ACEi and efferent glomerular arteriole dilates which promotes excretion of Na/H20 to reduce preload alongside systemic vasodilatation
ACE-inhibitors
Indications
HTN, CHF, IHD, diabetic nephropathy/CKD with proteinuria
ACE-inhibitors
Contraindications
RAS, AKI, pregnancy/breastfeeding
ACE-inhibitors
Side effects
Hypotension, dry cough, hyperkalaemia, angioedema
ACE-inhibitors
Interactions
K supplements/K sparing diuretics, NSAIDs
Angiontensin II Receptor Blockers
Names
Losartan, Candesartan, Irbesartan
Angiotensin II Receptor Blockers
Mechanism of Action
Block action of angiotensin II on AT1 receptor with similar effect to ACEi
Angiotensin II Receptor Blockers
Inidcations
Replace ACEi if cough not tolerated
Angiotensin II Receptor Blockers
Contraindications
RAS, AKI, pregnancy/breast feeding
Angiotensin II Receptor Blockers
Side Effects
Hypotension, hyperkalaemia, renal failure (short term)
Long term - cardiometabolic protective, renal protective
Angiotensin II Receptor Blockers
Interactions
Potassium supplements/K+ sparing diuretics, NSAIDs
Angiotensin II Receptor Blockers
Prescription Advice
No effect on bradykinin, less likely to cause angioedema, useful in Afro-Caribbean origin
Nitrates
Names
Isosorbide mononitrate (ISMN) glyceryl trinitrate (GTN)
Nitrates
Mechanism of Action
Nitrates are converted to NO which incerases cGMP and reduces Ca in smooth muscle cells (mostly venous) causing dilatation, reducing preload and LV filling, reduce workload and relieve angina
Nitrates
Indications
GTN - acute angina, ACS
ISMN - long acting prophylaxis of angina where CCB/BB are insufficient or given IV in pulmonary oedema treatment
Nitrates
Contraindications
Severe aortic stenosis, haemodynamic instability (esp hypotensive)
Nitrates
Side effects
Flushing, headaches, light-headedness, hypotension
Nitrates
Interactions
Phosphodiesterase inhibitor (sildenafil) - prolongs the effect can lead to severe hypotension
Digoxin
Cardiac Glycoside
Mechanism of Action
Inhibits Na/K-ATPase pumps to increase intracellular Ca (positively inotropic), also stimulates vagus nerve tone to reduce AV conduction rate (negatively chronotropic)
Digoxin
Indications
AF/AFl (if CCB/BB ineffective), severe heart failure
Digoxin
Contraindications
2nd degree heart block, intermittent complete heart block, ventricular arrhythmia, renal failure
Digoxin
Side Effects
Bradycardia, anorexia, rash, dizziness, visual disturbance (yellow-green vision), gynaecomastia
Digoxin
interactions
Diuretics, amiodarone, CCB, sprionolactone, quinine (all increase plasma concentration)
Can be precipitated by hypokalaemia
Amiodarone Class III (I) antiarrhythmic Mechanism of Action
Inhibits K+ channels to slow repolarisation, blocks Na channels to prevent depolarisation, slows conduction velocity, reduces ventricular rate can break arrhythmic circuit
Amiodarone
Indications
Tachyarrhythmias (AF, AFL, SVT, VT, refractoy VF) when other drugs are ineffective
Amiodarone
Contraindications
Severe hypotension, heart block, active thyroid disease
Amiodarone
Side effects
Hypotension Pneumonitis/Hepatitis Bradycardia Photosensitivity Skin becomes grey Thyroid change Corneal deposits Peripheral Neuropathy
Amiodarone
Interactions
Digoxin, dilitazem/verapamil
Aspirin
Anti-platelet
Mechanism of Action
Irreversible COX-inhibitor reduces thromboxane in arachidonic pathway to reduce platelet aggregation, wears off as new platelets are synthesised
Aspirin
Indications
ACS/Ischaemic stroke, long term preventative therapy, reduce risk of intracardiac thrombus in AF (if others contraindicated), control of moderate pain/fever
Aspirin
Contraindications
Children, post viral <16 (Reye’s syndrome of liver/brain), aspirin hypersensitivity, 3rd trimester (may close DA early), PUD, gout
Aspirin
Side Effects
GI irritation, ulceration/haemorrhage, bronchospasm, tinnitus, OD (leads to hyperventilation, metabolic acidosis, arrest)
Aspirin
Interactions
Synergistic with other anti-platelets/anti-coagulants
Clopidogrel
Antiplatelet
Mechanism of Action
Irreversibly binds ADP receptors on platelets to prevent coagulation
Clopidogrel
Indications
As aspirin:ACS/Ischaemic stroke, long term preventative therapy, reduce risk of intracardiac thrombus in AF (if others contraindicated)
Clopidogrel
Contraindications
Active bleeding, elective surgery (7-10 days as this is average lifespan of platelet)
Clopidogrel
Side effects
bleeding, thrombocytopenia, GI upset
Clopidogrel
Interactions
Pro-drug of CYP450 therefore inhibitors reduce efficacy (omeprazole, cipro, erythromycin, antifungals, some SSRIs), caution with other antiplatelets/coags
Tissue Plasminogen Activator (Fibrinolytics)
Names
Alteplase, Streptokinase
TPa
Mechanism of Action
Catalyse conversion of plasminogen to plasmin to dissolve fibrinous clots and recanalise occlude vessels to reperfuse affected tissue, very short half-life
TPa
Indications
Acute ischaemic stroke, acute STEMI, massive PE
TPa
Contraindications
Predisposition to bleeding, intracranial haemorrhage, previous streptokinase (risk of Abs if repeat dosing)
TPa
Side effects
N&V, bruising, hypotension, bleeding, allergic reaction, cardiogenic shock/arrest, reperfusion injury
TPa
Interactions
ACE-i increase risk of anaphylaxis
Risk of haemorrhage if also taking antiplatelet/coag
TPa
prescription advice
Injection only, dose based on weight
Heparin
Names
Enoxaparin, Dalteparin, Fondaparinux, Unfractioned heparin
Heparin
Mechanism of Action
UFH - activates antithrombin
LMWH - preferentially inhibit Xa to give predictable effect
Fondaparinux - only inhibits Xa, no monitoring needed, used in ACS
Heparin
Indications
VTE prophylaxis/treatment
ACS
Heparin
Contraindications
Bleeding, clotting disorders, severe uncontrolled hypertension, invasive procedures, renal impairment, falls risk
Heparin
Side effects
Bleeding, injection site reaction, heparin-induced-thrombocytopenia
Heparin
Interactions
Anthrombotics, can be reversed by protamine (excl fondaparinux)
Warfarin
Anticoagulant
Mechanism of Action
Inhibits vitamin K epoxide reductase to prevent coagulation factor synthesis of FX, IX, VII, II
Warfarin
Indications
Prevent VTE or embolism in AF/valve replacement, arterial events prevented by antiplatelets (not anticoagulant)
Warfarin
Contraindications
haemorrhage, liver disease, pregnancy
Warfarin
Side effects
Bleeding (epistaxis, retroperitoneal haemorrhage)
Warfarin
Interactions
Low TPI, metabolised by CYP450, also abx can reduce gut flora that synth vK so potentiate the effect
NOACs
Name
Rivaroxaban, Dabigatran, Apixaban
NOAC
Mechanism of action
Selectively inhibit FXa, and prothrombinase to to reduce thrombin
NOAC Indications
Thromboprophylaxis, warfarin substitute
NOAC
Contraindications
bleeding, artificial heart valve, clotting disorders, renal/hepatic impairment
NOAC
Side effects
Allergy, anaemia, tachycardia, hypotension
NOAC
Interactions
Other antiplatelets/anticoagulants
Statin
Name
Simvastatin
Atorvastatin
Pravastatin
Rosuvastatin
Statin
Mechanism of action
Inhibits HMG-CoA reductase, reducing LDL and increasing clearance and increases HDL to slow/reverse atherosclerotic process
Statin
Indications
Hyperlipidaemia, control of risk factors in CAD
Statin
Contraindications
Hepatic impairment, pregnant/breast feeding
Statin
Side effects
headache, muscle aches, rhabdomyolysis, increases liver enzymes
Statin
Interactions
Grapefruit juice, alcohol, CYP450 inhibitors (amiodarone, itraconazole, protease inhibitors)
Nicorandil
Indication/side effects
Second line anti-anginal
Causes serious mucosal ulceration, headache, flushing
Flecainide
Class 1c anti-arrhythmic
Pre-dose test
Contraindications
Potent sodium channel blocker
Echo to rule out structural ischaemic damage
Previous MI - electrical conduction already hindered
