CVS Flashcards
First line antihypertensive drugs: What does ABCD stand for
ACE inhibitor, Beta Blocker, Calcium Channel Blocker, Diuretics
ACE inhibitors: class, suffix, MOA, ADR, contraindications
Antihypertensive "-pril"s Short-acting: Enalapril, Captopril Long-acting: Benazepril Decrease Na, H2o retention by decreasing aldosterone Block bradykinin breakdown (by AGII), bradykinins cause the release of NO for vasodilation ADR: Angioedema and dry cough Contraindicated in pregnancy
Ag II T1 blockers: class, suffix, MOA, ADR, contraindications
Antihypertensive
“-sartan”s
Direct blockage of AT1 receptors
Contraindicated in pregnancy
B-Blockers: class, suffix, MOA, ADR, contraindications
Antihypertensive, ischemic HD, anti-arrythmia
Cardioselective B1 blockers (MANBABE)
HTN, Ischemia: Block cAMP, decrease Myocin-LC activation, decrease Ca2+ influx to decrease contractility
Arrythmia: Negative inotropic effect (prolongs AV conduction)
Bradycardia, bronchoconstriction, cardiac depression
Contraindicated in diabetics, asthmatics
CCB: class, name, MOA, ADR, contraindications
Antihypertensives, ischemic heart disease
Inhibit channel to decrease Ca influx and calmodulin signalling, decreases Myosin LC activation
Nifedipine- DHP more vascular selective
Decrease vascular smooth muscle tone, vasodilation decrease oxygen requirement and BP
Verapamil- NDHP more cardiac muscle selective
Decrease SA, AV nodal conduction, decrease contractility
Used for supraventricular tachycardia, arrythmia because of negative chronotropic effect
Cannot use on HF patients because cardiac depression. Only for angina and hypertension
Loop diuretics: class, suffix, MOA, ADR, contraindications
Antihypertensives, HF
Sulfonamide derivatives (furosemide)
Act at ascending limb, selectively inhibit Na/K/Cl cotransporter at luminal side to prevent Na reabsorption
Increase renal blood flow to increase GFR
Hypokalemic alkalosis because of more K+, H+ excretion
Ionic imbalance of Mg, Ca because less driving force
Ototoxicity, cannot take with aminoglycosides
DCT diuretics: class, suffix, MOA, ADR, contraindications
Antihypertensives, HF
Thiazides
Act at DCT. Blocks Na/Cl cotransport but enhance Ca2+ reabsorption
Hypokalemic alkalosis, more K+, H+ secretion
Potassium-sparing diuretics: class, suffix, MOA, ADR, contraindications
HF
SEAT: Spironolactone, Eplerenone, Amilioride, Triamterene
Target K+ secretion at collecting duct. To decrease Na+ reabsorption and K+ secretion.
S and E inhibit aldosterone receptor and T and A inhibit Na+ channel protein.
Hyperkalemia, metabolic acidosis, gynaecomastia
Type I hyperlipoproteinemia
Familial hyperchylomicronemia, raised CM levels
Due to LPL deficiency
Type II hyperlipoproteinemia + tx
IIa: f. hypercholesterolemia, raised LDL.
IIb: mixed hyperlipidemia, raised VLDL and LDL.
tx: Statin
Type IV hyperlipoproteinemia + tx
Familial hypertriglyceridemia, raised VLDL tx: niacin, vit B3
First line drug for Type II (TG<4.5mmol/L)
Statins
First line drug for Type II (TG>4.5mmol/L)
Fibrates to lower risk of pancreatitis, niacin if severe
Niacin: class, MOA, ADR, contraindications
Lipid-lowering by inhibiting HSL
Inhibiting HSL to prevent lipolysis in tissues. Hence, lower amount of VLDLs needed to transport TGs out of liver
Most potent in increasing HDL
Flushing (first few days), hyperuricemia and GOUT
Cholestyramine, Cholestipol: class, MOA, ADR, contraindications
Lipid-lowering by lowering bile acid concentration (+ve bind to -ve salts), liver uses more cholesterol to produce bile acids
Useful in isolated LDL increase only, causes HMG-CoA reductase to be upregulated so often used with statin
Cause bloating and abdominal discomfort
May cause impaired vitamin ADEK absorption
Contraindicated in pregnancy
Ezetimibe: class, MOA, ADR, contraindications
Lipid-lowering by impairing cholesterol absorption
Selectively inhibits cholesterol transport protein NPC1L1
Often combined with statin
Contraindicated in pregnancy
Gemfibrozil: class, MOA, ADR, contraindications
Lipid-lowering by increasing LPL activity
Fibrates
Peripheral clearance effect because act as ligands for PPAR-a, increasing FFA uptake and decreasing liver TG levels, less VLDL needed
Upregulate Apo-A proteins (on HDL)
Contraindicated in pregnancy
DDI: Displace warfarin in albumin-binding, interferes with clearance of statins
Statins: class, MOA, ADR, contraindications
Lipid-lowering by inhibiting HMG-CoA reductase
Competitive inhibitor at rate-limiting step of cholesterol synthesis
Peripheral clearance effect as LDL receptors upregulated to take in more cholesterol
**Fibrinolytic, helps with atherosclerosis
Take in evening, cholesterol levels highest in fasting state
Contraindicated in pregnancy
Hepatotoxicity, myotoxicity, nausea, cataracts, rash, headache
Metabolised by CYP450
Mode of administration: Lipid-lowering drugs
Oral, except PCSK9 antibodies (subq)
Only lipid-lowering drug that is not contraindicated in pregnancy
Omega 3 FA
What are the factors affecting cardiac oxygen requirement?
Preload (which depends on blood volume and venous tone), afterload (which depends on arterial BP), heart rate, contractility
Nitrates: class, name, MOA, ADR, contraindications
Ischemic heart disease
Nitroglycerin, nitroprusside (SNP)
Donates nitrite which is converted to NO needed for guanylyl cyclase pathway, cGMP needed to dephosphorylate myosin LC.
Smooth muscle relaxation causes vasodilation to decrease preload and afterload. Vein dilation reduces preload and arterial dilation reduces TPR (afterload). Coronary artery dilation also increases oxygenation.
Tachycardia baroreflex (temporary), hypotension, headache (meningeal artery dilation)
Long term: Tolerance (tissue thiols depleted)
SNP produces cyanide as by-product, risk of poisoning
NSAIDs: class, name, MOA, ADR, contraindications
Antiplatelet
Aspirin
Irreversible COX inhibitor, prevent TXA2 synthesis by platelets when they want to aggregate
Bleeding and peptic ulcers because inhibitory towards PG synthesis
GPIIb/IIIa fibrinogen receptor antagonists: class, name, MOA, ADR, contraindications
Antiplatelet
Abciximab
mAb against receptor found on platelet membrane
For high risk angioplasty patients, given with aspirin and heparin
Bleeding, thrombocytopenia
aPTT vs PT
aPTT: activated partial thromboplastin time, intrinsic pathway (damage to endothelium). Used to monitor heparin
PT: prothrombin time, extrinsic pathway (external trauma causing tissue factor release). Used to monitor warfarin
Vit K dependent factors
2, 7, 9, 10
Heparin: class, MOA, ADR, contraindications
Anticoagulant
AT3 potentiator, enhances binding to clotting factors 2a, 9a, 10a by 1000x
Given with GP11b/IIIa blockers for angioplasty
Short term: allergy
Long term: osteoporosis, transient reversible hair loss
Warfarin: class, MOA, ADR, contraindications
Anticoagulant
Inhibit Vit K reductase, factor 2, 7, 9, 10 cannot be activated as reduced bit K is used as a cofactor for gamma carboxylation for these factors
Contraindication: PREGNANCY
Narrow TI, albumin-bound (risk of bleeding)
Metabolised by CYP450
Teratogen, risk of cutaneous necrosis
Difference in use of heparin and warfarin (hint: difference in onset time, mode of administration and side effects)
Heparin used to induce anticoagulation especially in DVT and PE (immediate onset, administer via subq), warfarin to maintain in the long run.
When can reduced and oxidised vit K be administered?
Reduced vit k needed for clotting (activate factors 2, 7, 9, 10), can be used to treat bleeding caused by warfarin. Oxidised vit k given to “overwork” vit K reductase to slow down carboxylation of glutamate residues of the clotting factors.
Tissue plasminogen activators: class, names, MOA, ADR, contraindications
Thrombolytic agents
t-PA, Urokinase, streptokinase
Essentially all are t-PA, converts plasminogen to plasmin which degrades fibrin. For emergency use to lyse clots
Diuretics in edematous patient with CHF
Thiazide if not severe, furosemide if severe. Need to manage hypokalemia by using potassium-sparing diuretic or potassium supplement
First line drug in non-edematous patient with CHF
ACE Inhibitors decrease preload and afterload.
Pathophysiology of CHF
Causes of LHF: IHD, aortic stenosis, CoA, pericardial effusion
As heart becomes less effective, preload increases as more blood remains in heart after each cycle. Heart becomes overstretches because it cannot fully compensate
Classes of anti-arrhythmics
Class 1: SCB Class 2: BB Class 3: PCB Class 4: NHDPCCB Adenosine
Which class of anti-arrhythmics is used for supraventricular tachycardia?
Class 4 NHDPCCB- Verapamil, Diltiazem are more myocardial selective
Reduces AV conductivity, prolongs phase 4 depolarisation
Adenosine also used, but half like only 10s and for emergency use
Which class of anti-arrythmics is used for atrial fibrillation?
On top of Beta Blockers,
Class 3 PCB- Amiodarone
Prolongs phase 3 repolarisation, no phase 0 effect (phase 0 only sodium channels open)
Increases ERP and APD
3 sodium channel blockers
Class 1A: Procainamide
Class 1B: Lidocaine
Class 1C: Flecainide (last resort, may increase mortality)
GTN vs SNP: Mode of administration
GTN : Oral
SNP: IV
