CV drugs Flashcards
What are the drug classes used in treatment of hypertension?
- Vasodilators (ACE Inhibitors, ARBs, Alpha-antagonists)
- Calcium channel blockers
- Diuretics
- Beta-blockers
How do ACE inhibitors work?
-block conversion of angiotensin I to angiotensin II
ACEI used?
Lisinopril
side effects: dry cough, hypotension (precipitated by diuretics)
Angiotensin Receptor Blockers’ mode of action?
Competitive antagonists of AT1 receptor. ARBs cause venous and arteriolar dialation
ARB prescribed?
Losartan
CCBs’ mode of action?
Antagonists of the L-type Ca channels. Reduced Ca entry into smooth muscle causes reduced contraction/constriction and TPR
CCBs prescribed?
Amplodipine (a dihydropyridine)
Verpamil and Diltiazem
CCB side effects?
ankle oedema
hypotension
dizziness
Amlodipine is more selective for vascular smooth muscle - less side effects on myocardium.
Do NOT use CCB with Beta-blockers.
How do Thiazide-like diuretics work?
Promote Na excretion by inhibiting its reabsorption from the loop of Henle.
Thiazide diuretic prescribed?
Bendroflumethiazide
side effects:
- hypokalaemia (tiredness, arrhythmias)
- hyperglycaemia (diabetes)
- hyperuricaemia (gout)
- impotence
Used in resistant hypertension?
Spironolactone
Side effect: hyperkalaemia
Classes of anti-thrombolytic drugs?
Antiplatelet
anticoaggluants
fibrinolytics
Antiplatelet drugs prescribed?
Aspirin
Clopidogrel
Tricagrelor
Prasugrel
use: angina, MI, TIA, stroke
Side effects: haemorrhage
Anticoagulats prescribed?
Prevent new thrombosis
Warfarin (blocks clotting factors)
Heparin
Rivaroxaban (inhibits clotting factor Xa)
Dabigatran (inhibits factor IIa - thrombin)
side effects: haemorrhage
Fibirnolytic prescribed?
Streptokinase
- (dissolves formed clots)
- use in STEMI, PE
Classes of anti-cholsterol drugs?
statins
fibrates
ezetimibe
bile binding resins
Statins used? Mode of action?
Simvastatin, Atorvastatin
Block the HMG CoA reductase, reducing LDL produciton in the liver.
Use in: hypercholesteraemia, angina/MI, TIA
Side effects of statins?
myopathy
rhabdomyolysis
renal failure
NOT in pregnancy
Fibrates used? Mode of action?
Bezafibrate, Gemifibrozil
Lower the trigylceride, LDL levels
Use for: hypertriglyceridaemia
low HDL cholesterol
How does Ezetimibe work?
Inhibits cholesterol absorption in the duodenum.
Used with statins.
Bile acid binding resins?
Colestyramine
Promote bile secretion, leading to increased conversion of cholsterol to bile components.
Anti-anginal drug classes?
- β Blockers
- Ca2+ Channel Blockers
- Nitrates
- K+ channel Openers
Examples of CCBs?
Mode of action?
Amlodipine,
Verapamil, Diltiazem
Inhibit calcium entry into vascular smooth muscle, causing peripheral arteriolar dilatation.
CCB side effects?
ankle oedema
hypotension
dizziness
β Blocker (cardioselective) prescribed?
Atenolol
Recuces heart rate and force, reducing the Oxygen requirement of the myocardium.
β Blockers’ (Atenolol) side effects?
cold peripheries
bradycardia
fatigue
Long term - heart failure
Do NOT use in asthma.
Nitrates used in angina?
How do they work?
GTN (glycerylnitrate)
Releases NO, which relaxes smooth muscle.
Dilates collateral arterioles in angina, directing blood to ischaemic zones.
Side effects: postural hypotension, tolerance
Potassium Channel Opener used in angina?
Nicorandil
Promotes K+ efflux, causing hyperpolarisation, leading to muscle relaxation and coronary vasodilation.
Side effects: hypovolaemia (low BP).
What are the antiarrhythmic drug classes?
Class I (IA, IB, IC)
Class II
Class III
Class IV
How do Class I antiarrhytmic drugs work?
Examples?
Block voltage-activated Na+ channels
Disopyramide (IA)
Lignocaine (IB)
Flecanide (IC)
How do Class II antiarrhytmic drugs work?
Example?
Antagonists of β-adrenoreceptors, slow down depolarisation in the SA and AV nodes.
Metaprolol
How do Class III antiarrhytmic drugs work?
Example?
Block voltage-activated K+ channels, increasing the duration of the action potential.
Amiodarone
How do Class IV antiarrhytmic drugs work?
Example?
Block voltage-activated Ca2+ channels, decreasing the force of contraction.
Verapamil
Side effects of antiarrhythmic drugs?
phototoxicity
pulmonary fibrosis
thyroid abnormalities
How do Inotropic drugs work?
Examples?
Modify the force or speed of contraction:
- Digoxin
- β-Adrenoceptor Agonists
- Cakcium-sensitizers
How does Digoxin work?
Side effects?
Blocks atrial-ventricular conduction, causing an AV delay.
Side effects: It increases ventricular irritability, causing ventricular arrhythmias.
Nausea, vomiting, bradycardia.
What is the mode of action of β-adrenoceptor agonists?
Example? When is it used?
Increase force and rate of contraction.
Adrenaline (use in anaphylactic shock and cardiac arrest)
side effect: arrhythmias
Example of Calcium-sensitizers?
When is it used?
Levosimedan
Binds to troponin C, sensitizing it to Calcium ions.
Use in: acute decompensated heart failure
What is Atropine’s mode of action?
When is it used?
A non-selective muscarinic Ach receptor antagonist.
Increases HR at >600mg doses
Use for: first line in severe Bradycardia
