Pharmacology and Drugs for Cardiovascular Disease Flashcards
What end organ damage can hypertension cause?
Brain: thrombotic, thromboembolic, hemorrhagic stroke
Heart: LVH, LV failure, coronary artery disease
Kidney: renal failure
Eyes: hypertensive retinopathy
Major risk factors for cerebrovascular atherosclerosis?
Hypertension Smoking Diabetes Hyperlipidemia Obesity
What does the prognosis of hypertension depend on?
Level of systolic and diastolic BP
Age, sex, diabetes
Worse if evidence of end-organ damage
Improved with antihypertensive therapy
Non-pharmacological treatment of hypertension?
Weight reduction
Reduce salt, alcohol and fat intake
Exercise
Smoking cessation
List the common antihypertensive drugs?
Thiazide diuretics ACE inhibitors Angiotensin II receptor antagonists Beta blockers Ca channel blockers Alpha blockers
How to thiazide diuretics work?
Inhibit reabsorption of NaCl in proximal and early distal tubules of nephron
What is the most common thiazide?
Which one is used for severe congestive heart failure?
Bendroflumethiazide
Metolazone in combo with loop diuretics
Side effects of thiazide diuretics?
Electrolyte disturbance
Rash
Postural hypotension
What is the renin angiotensin system?
Angiotensinogen - angiotensin 1 - ACE - angiotensin II - Aldosterone from adrenal gland = decrease ECF, BP or Na = Renin released from juxtaglomerular cells
What do ACE inhibitors do?
Inhibit the conversion of angiotensin I to angiotensin II
Side effects of ACE inhibitors?
Dry cough, hypotension, rash, hyperkalaemia, renal failure, angioedema
What do angiotensin II receptor antagonists (ARBs) do?
Similar effects to ACE inhibitors but do NOT inhibit bradykinin metabolism = do not cause dry cough
e.g. Losartan, valsartan
What do beta blockers (beta-adrenoceptor antagonists) do?
Reduce HR, BP and CO
Contraindications of beta blockers?
Asthma, uncontrolled heart failure, bradycardia
Side effects of beta blockers?
Fatigue, hypotension, cold peripheries, bronchospasm
What do calcium channel antagonists do?
Vasodilators - reduce systemic vascular tone
Types of calcium channel antagonists?
Verapamil and diltiazem - cause bradycardia, inhibit AV node conduction
Amlodipine, lercanidipine - may cause a reflex tachycaradia
Side effects of calcium channel antagonists?
Oedema Flushing Headache Dizziness Hypotension
Name the vasodilators used to treat hypertension
Alpha blockers: doxazosin Hydralazine Methyldopa (can be used in pregnancy)
Side effects of vasodilators treating hypertension?
Hypotension
Headache
Tachycardia
Oedema
What is ischaemic heart disease?
Atherosclerosis of coronary arteries that may lead to stenosis and arterial thrombosis
How does atherosclerosis progress?
Fatty streak - fibrous plaque - atherosclerotic plaque = angina, transient ischaemic attack = plaque rupture/fissure and thrombosis = MI, ischaemic stroke, critical leg ischaemia, CV death
List anti-anginal drugs
Beta blockers
Nitrates
Ca channel blockers
Potassium channel activators
What to beta blockers do?
Lower myocardial oxygen demand by reducing HR, BP and myocardial contractility
May exacerbate cardiac failure and peripheral vascular disease and cause bronchospasm
What may beta blockers exacerbate?
May exacerbate cardiac failure and peripheral vascular disease and cause bronchospasm
What can abrupt withdrawal of beta blockers do?
Arrhythmia, worsening angina or MI
How can nitrates be taken?
Oral, sublingual, buccal, transdermal, intravenous
What do nitrates provide? How?
Symptomatic relief of angina
Produce nitric oxide at the endothelial surface leading to vascular smooth muscle relaxation and arteriolar and venous dilation
Reduce myocardial oxygen demand and increase myocardial oxygen supply
Side effects of nitrates?
Headache, flushing, postural hypotension
What do calcium antagonists do?
Lower myocardial oxygen demand by reducing blood pressure and myocardial contractility and increase myocardial oxygen supply by dilating coronary arteries
What calcium antagonists should be avoided in heart failure?
Verapamil and Diltiazem
How do potassium channel activators work?
They have arterial and venous dilating properties
What can potassium channel activators cause?
Mucocutaneous ulceration
How do antiplatelet drugs work?
Inhibit platelet aggregation and arterial thrombus formation = prevent heart attack, stroke and CV death
Give examples of antiplatelet drugs and how do they work?
Aspirin - blocks COX11 and production of thromboxane A2 (platelet activating substance)
Clopidogrel, prasugrel, ticagrelor - platelet P2Y12 receptor inhibitors, used in combo with aspirin or alone
Dipyridamole - in combo with aspirin to prevent stroke
What are statins? What do they do?
HMG CoA reductase inhibitors
Lower LDL cholesterol and may increase HDL cholesterol
Reduce risk of MI, stroke and CV death
Examples of statins?
Simvastatin, pravastatin, atorvastatin
What is heart failure?
The state that develops when the heart cannot maintain an adequate cardiac output or can do so only at the expense of an elevated filling pressure
How to treat chronic heart failure?
Diuretics, ACE inhibitors, Beta blockers, Aldosterone antagonists
How do diuretics work on the kidney?
Thiazides - inhibit Cl-Na active exchange in the ascending loop of Henle
K-sparing = inhibit reab of Na in the collecting tubule
Loop diuretics = acts on medulla, inhibit Cl-Na-K exchange in the thick segment of the ascending loop of Henle
What are Tachyarrhythmias? Types?
Abnormal heart rhythm
Atrial fibrillation or atrial flutter with rapid ventricular rate response (AF)
Supraventricular tachycardia (SVT)
Ventricular tachycardia (VT)
What does digoxin (digitalis) do?
Blocks Na/K ATPase => Ca
Increase vagal tone - slows conduction in atrial fibrillation
Classification of oral antiarrhythmics?
Class Ia,b,c – disopyramide, flecainide, procainamide
Class II – beta blockers
Class III – amiodarone, dronedarone, sotalol
Class IV – calcium antagonists (verapamil, diltiazem)
