Pharmacology Drugs that Affect the Cardiovascular System
Topics <ul><li>Electrophysiology </li></ul><ul><li>Vaughn-Williams classification </li></ul><ul><li>Antihypertensives </li...
Cardiac Function <ul><li>Dependent upon </li></ul><ul><ul><li>Adequate amounts of ATP </li></ul></ul><ul><ul><li>Adequate ...
Adequate Amounts of ATP <ul><li>Needed to: </li></ul><ul><ul><li>Maintain electrochemical gradients </li></ul></ul><ul><ul...
Adequate Amounts of Calcium <ul><li>Calcium is ‘glue’ that links electrical and mechanical events. </li></ul>
Coordinated Electrical Stimulation <ul><li>Heart capable of automaticity </li></ul><ul><li>Two types of myocardial tissue ...
A.P. SuperHighway <ul><li>Sinoatrial node </li></ul><ul><li>Atrioventricular node </li></ul><ul><li>Bundle of His </li></u...
Electrophysiology <ul><li>Two types of action potentials </li></ul><ul><ul><li>Fast potentials </li></ul></ul><ul><ul><ul>...
Fast Potential -80 -60 -40 -20 0 +20 RMP -80 to 90 mV Phase 1 Phase 2 Phase 3 Phase 4 controlled by Na + channels =  “fast...
Fast Potential <ul><li>Phase 0: Na +  influx “fast sodium channels” </li></ul><ul><li>Phase 1: K  +  efflux </li></ul><ul>...
Cardiac Conduction Cycle
Slow Potential -80 -60 -40 -20 0 Phase 4 Phase 3 dependent upon Ca ++  channels =  “slow channels”
Slow Potential <ul><li>Self-depolarizing </li></ul><ul><ul><li>Responsible for automaticity </li></ul></ul><ul><li>Phase 4...
Cardiac Pacemaker Dominance <ul><li>Intrinsic firing rates: </li></ul><ul><ul><li>SA = 60 – 100  </li></ul></ul><ul><ul><l...
Cardiac Pacemakers <ul><li>SA is primary </li></ul><ul><ul><li>Faster depolarization rate </li></ul></ul><ul><ul><ul><li>F...
Potential Terms APD ERP RRP relative  refractory period effective refractory period action potential duration
Dysrhythmia Generation <ul><li>Abnormal genesis </li></ul><ul><ul><li>Imbalance of ANS stimuli </li></ul></ul><ul><ul><li>...
Dysrhythmia Generation <ul><li>Abnormal conduction </li></ul><ul><li>Analogies: </li></ul><ul><ul><li>One way valve </li><...
Reentrant Circuits
Warning! <ul><li>All antidysrhythmics have arrythmogenic properties </li></ul><ul><li>In other words, they all can CAUSE d...
AHA Recommendation Classifications <ul><li>Describes weight of supporting evidence NOT mechanism </li></ul><ul><li>Class I...
Vaughn-Williams Classification <ul><li>Class 1 </li></ul><ul><ul><li>Ia </li></ul></ul><ul><ul><li>Ib </li></ul></ul><ul><...
Class I: Sodium Channel Blockers <ul><li>Decrease Na +  movement in phases 0 and 4 </li></ul><ul><li>Decreases rate of pro...
Class Ia Agents <ul><li>Slow conduction through ventricles </li></ul><ul><li>Decrease repolarization rate </li></ul><ul><u...
Class Ib Agents <ul><li>Slow conduction through ventricles </li></ul><ul><li>Increase rate of repolarization </li></ul><ul...
Class Ic Agents <ul><li>Slow conduction through ventricles, atria & conduction system </li></ul><ul><li>Decrease repolariz...
Class II: Beta Blockers <ul><li>Beta 1  receptors in heart attached to Ca ++  channels </li></ul><ul><ul><li>Gradual Ca ++...
Class II: Beta Blockers <ul><li>propranolol (Inderal ® ) </li></ul><ul><li>acebutolol (Sectral ® ) </li></ul><ul><li>esmol...
Class III: Potassium Channel Blockers <ul><li>Decreases K +  efflux during repolarization </li></ul><ul><li>Prolongs repol...
Class IV: Calcium Channel Blockers <ul><li>Similar effect as  ß  blockers </li></ul><ul><li>Decrease SA/AV automaticity </...
Misc. Agents <ul><li>adenosine (Adenocard ® ) </li></ul><ul><ul><li>Decreases Ca ++  influx & increases K +  efflux via 2 ...
Misc. Agents <ul><li>Cardiac Glycocides </li></ul><ul><li>digoxin (Lanoxin ® ) </li></ul><ul><ul><li>Inhibits NaKATP pump ...
Pharmacology Antihypertensives
Antihypertensive Classes <ul><li>diuretics </li></ul><ul><li>beta blockers </li></ul><ul><li>angiotensin-converting enzyme...
Blood Pressure = CO X PVR <ul><li>Cardiac Output = SV x HR </li></ul><ul><li>PVR = Afterload </li></ul>
BP = CO x PVR Key: CCB = calcium channel blockers CA Adrenergics = central-acting adrenergics ACEi’s = angiotensin-convert...
BP = CO x PVR Peripheral Sympathetic Receptors alpha   beta 1. alpha blockers  2.  beta blockers Local Acting 1. Periphera...
Alpha 1  Blockers <ul><li>Stimulate alpha 1  receptors -> hypertension </li></ul><ul><li>Block alpha 1  receptors -> hypot...
Central Acting Adrenergics <ul><li>Stimulate alpha 2  receptors  </li></ul><ul><ul><li>inhibit alpha 1  stimulation </li><...
Peripheral Acting Adrenergics <ul><li>reserpine (Serpalan ® ) </li></ul><ul><li>inhibits the release of NE </li></ul><ul><...
Adrenergic Side Effects <ul><li>Common </li></ul><ul><ul><li>dry mouth, drowsiness, sedation & constipation </li></ul></ul...
ACE Inhibitors  Angiotensin I ACE Angiotensin II 1. potent vasoconstrictor - increases BP 2. stimulates Aldosterone - Na +...
Renin-Angiotensin Aldosterone System <ul><li>Angiotensin II  = vasoconstrictor </li></ul><ul><li>Constricts blood vessels ...
ACE Inhibitors <ul><li>Aldosterone secreted from adrenal glands cause sodium & water reabsorption </li></ul><ul><li>Increa...
Angiotensin Converting Enzyme Inhibitors <ul><li>captopril (Capoten ® ) </li></ul><ul><li>enalapril (Vasotec ® ) </li></ul...
Calcium Channel Blockers <ul><li>Used for: </li></ul><ul><ul><li>Angina </li></ul></ul><ul><ul><li>Tachycardias </li></ul>...
CCB Site of Action diltiazem & verapamil nifedipine  (and other dihydropyridines )
CCB Action <ul><li>diltiazem & verapamil </li></ul><ul><ul><li>decrease automaticity & conduction in SA & AV nodes </li></...
Side Effects of CCBs <ul><li>Cardiovascular </li></ul><ul><ul><li>hypotension, palpitations & tachycardia </li></ul></ul><...
Calcium Channel Blockers <ul><li>diltiazem (Cardizem ® ) </li></ul><ul><li>verapamil (Calan ® , Isoptin ® ) </li></ul><ul>...
Diuretic Site of Action . loop of Henle proximal tubule Distal tubule Collecting duct
Mechanism <ul><li>Water follows Na + </li></ul><ul><li>20-25% of all  Na +  is reabsorbed into the blood stream in the loo...
Side Effects of Diuretics <ul><li>electrolyte losses [ Na +  &  K +  ] </li></ul><ul><li>fluid losses [dehydration] </li><...
Diuretics <ul><li>Thiazides: </li></ul><ul><ul><li>chlorothiazide (Diuril ® ) & hydrochlorothiazide (HCTZ ® , HydroDIURIL ...
Mechanism of Vasodilators <ul><li>Directly relaxes arteriole smooth muscle </li></ul><ul><li>Decrease SVR = decrease after...
Side Effects of Vasodilators <ul><li>hydralazine (Apresoline ® ) </li></ul><ul><ul><li>Reflex tachycardia </li></ul></ul><...
Vasodilators <ul><li>diazoxide [Hyperstat ® ] </li></ul><ul><li>hydralazine [Apresoline ® ] </li></ul><ul><li>minoxidil [L...
Pharmacology Drugs Affecting Hemostasis
Hemostasis <ul><li>Reproduce figure 11-9, page 359 Sherwood  </li></ul>
Platelet Adhesion
Coagulation Cascade <ul><li>Reproduce following components of cascade: </li></ul><ul><ul><li>Prothrombin -> thrombin  </li...
Platelet Inhibitors <ul><li>Inhibit the aggregation of platelets </li></ul><ul><li>Indicated in progressing MI, TIA/CVA </...
Aspirin <ul><ul><li>Inhibits COX </li></ul></ul><ul><ul><ul><li>Arachidonic acid (COX) -> TXA2 (   aggregation) </li></ul...
GP IIB/IIIA Inhibitors GP  II b/ III a Inhibitors Fibrinogen GP  II b/ III a Receptor
GP IIB/IIIA Inhibitors <ul><li>abciximab (ReoPro ® ) </li></ul><ul><li>eptifibitide (Integrilin ® ) </li></ul><ul><li>tiro...
Anticoagulants <ul><li>Interrupt clotting cascade at various points </li></ul><ul><ul><li>No effect on platelets </li></ul...
Heparin <ul><li>Endogenous </li></ul><ul><ul><li>Released from mast cells/basophils </li></ul></ul><ul><li>Binds with  ant...
Heparin <ul><li>Measured in Units, not milligrams </li></ul><ul><li>Indications: </li></ul><ul><ul><li>MI, PE, DVT, ischem...
warfarin (Coumadin ® ) <ul><li>Factors II, VII, IX and X all vitamin K dependent enzymes </li></ul><ul><li>Warfarin compet...
Thrombolytics <ul><li>Directly break up clots </li></ul><ul><ul><li>Promote natural thrombolysis </li></ul></ul><ul><li>En...
Occlusion Mechanism
tPA Mechanism
Cholesterol Metabolism <ul><li>Cholesterol important component in membranes and as hormone precursor </li></ul><ul><li>Syn...
Lipoproteins <ul><li>Lipids are surrounded by protein coat to ‘hide’ hydrophobic fatty core. </li></ul><ul><li>Lipoprotein...
Why We Fear Cholesterol <ul><li>Risk of CAD linked to LDL levels </li></ul><ul><li>LDLs are deposited under endothelial su...
Why We Fear Cholesterol <ul><li>Plaque cap can rupture </li></ul><ul><li>Collagen exposed </li></ul><ul><li>Clotting casca...
Lipid Deposition
Thrombus Formation
Platelet Adhesion
Embolus Formation
Occlusion Causes Infarction
Antihyperlipidemic Agents <ul><li>Goal: Decrease LDL </li></ul><ul><ul><li>Inhibition of LDL synthesis </li></ul></ul><ul>...
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Cardiac drugs

  1. 1. Pharmacology Drugs that Affect the Cardiovascular System
  2. 2. Topics <ul><li>Electrophysiology </li></ul><ul><li>Vaughn-Williams classification </li></ul><ul><li>Antihypertensives </li></ul><ul><li>Hemostatic agents </li></ul>
  3. 3. Cardiac Function <ul><li>Dependent upon </li></ul><ul><ul><li>Adequate amounts of ATP </li></ul></ul><ul><ul><li>Adequate amounts of Ca ++ </li></ul></ul><ul><ul><li>Coordinated electrical stimulus </li></ul></ul>
  4. 4. Adequate Amounts of ATP <ul><li>Needed to: </li></ul><ul><ul><li>Maintain electrochemical gradients </li></ul></ul><ul><ul><li>Propagate action potentials </li></ul></ul><ul><ul><li>Power muscle contraction </li></ul></ul>
  5. 5. Adequate Amounts of Calcium <ul><li>Calcium is ‘glue’ that links electrical and mechanical events. </li></ul>
  6. 6. Coordinated Electrical Stimulation <ul><li>Heart capable of automaticity </li></ul><ul><li>Two types of myocardial tissue </li></ul><ul><ul><li>Contractile </li></ul></ul><ul><ul><li>Conductive </li></ul></ul><ul><li>Impulses travel through ‘action potential superhighway’. </li></ul>
  7. 7. A.P. SuperHighway <ul><li>Sinoatrial node </li></ul><ul><li>Atrioventricular node </li></ul><ul><li>Bundle of His </li></ul><ul><li>Bundle Branches </li></ul><ul><ul><li>Fascicles </li></ul></ul><ul><li>Purkinje Network </li></ul>
  8. 8. Electrophysiology <ul><li>Two types of action potentials </li></ul><ul><ul><li>Fast potentials </li></ul></ul><ul><ul><ul><li>Found in contractile tissue </li></ul></ul></ul><ul><ul><li>Slow potentials </li></ul></ul><ul><ul><ul><li>Found in SA, AV node tissues </li></ul></ul></ul>
  9. 9. Fast Potential -80 -60 -40 -20 0 +20 RMP -80 to 90 mV Phase 1 Phase 2 Phase 3 Phase 4 controlled by Na + channels = “fast channels”
  10. 10. Fast Potential <ul><li>Phase 0: Na + influx “fast sodium channels” </li></ul><ul><li>Phase 1: K + efflux </li></ul><ul><li>Phase 2: (Plateau) K + efflux </li></ul><ul><ul><li>AND Ca + + influx </li></ul></ul><ul><li>Phase 3: K + efflux </li></ul><ul><li>Phase 4: Resting Membrane Potential </li></ul>
  11. 11. Cardiac Conduction Cycle
  12. 12. Slow Potential -80 -60 -40 -20 0 Phase 4 Phase 3 dependent upon Ca ++ channels = “slow channels”
  13. 13. Slow Potential <ul><li>Self-depolarizing </li></ul><ul><ul><li>Responsible for automaticity </li></ul></ul><ul><li>Phase 4 depolarization </li></ul><ul><ul><li>‘ slow sodium-calcium channels’ </li></ul></ul><ul><ul><li>‘ leaky’ to sodium </li></ul></ul><ul><li>Phase 3 repolarization </li></ul><ul><ul><li>K + efflux </li></ul></ul>
  14. 14. Cardiac Pacemaker Dominance <ul><li>Intrinsic firing rates: </li></ul><ul><ul><li>SA = 60 – 100 </li></ul></ul><ul><ul><li>AV = 45 – 60 </li></ul></ul><ul><ul><li>Purkinje = 15 - 45 </li></ul></ul>
  15. 15. Cardiac Pacemakers <ul><li>SA is primary </li></ul><ul><ul><li>Faster depolarization rate </li></ul></ul><ul><ul><ul><li>Faster Ca ++ ‘leak’ </li></ul></ul></ul><ul><li>Others are ‘backups’ </li></ul><ul><ul><li>Graduated depolarization rate </li></ul></ul><ul><ul><ul><li>Graduated Ca ++ leak rate </li></ul></ul></ul>
  16. 16. Potential Terms APD ERP RRP relative refractory period effective refractory period action potential duration
  17. 17. Dysrhythmia Generation <ul><li>Abnormal genesis </li></ul><ul><ul><li>Imbalance of ANS stimuli </li></ul></ul><ul><ul><li>Pathologic phase 4 depolarization </li></ul></ul><ul><ul><ul><li>Ectopic foci </li></ul></ul></ul>
  18. 18. Dysrhythmia Generation <ul><li>Abnormal conduction </li></ul><ul><li>Analogies: </li></ul><ul><ul><li>One way valve </li></ul></ul><ul><ul><li>Buggies stuck in muddy roads </li></ul></ul>
  19. 19. Reentrant Circuits
  20. 20. Warning! <ul><li>All antidysrhythmics have arrythmogenic properties </li></ul><ul><li>In other words, they all can CAUSE dysrhythmias too! </li></ul>
  21. 21. AHA Recommendation Classifications <ul><li>Describes weight of supporting evidence NOT mechanism </li></ul><ul><li>Class I </li></ul><ul><li>Class IIa </li></ul><ul><li>Class IIb </li></ul><ul><li>Indeterminant </li></ul><ul><li>Class III </li></ul><ul><li>View AHA definitions </li></ul>
  22. 22. Vaughn-Williams Classification <ul><li>Class 1 </li></ul><ul><ul><li>Ia </li></ul></ul><ul><ul><li>Ib </li></ul></ul><ul><ul><li>Ic </li></ul></ul><ul><li>Class II </li></ul><ul><li>Class III </li></ul><ul><li>Class IV </li></ul><ul><li>Misc </li></ul><ul><li>Description of mechanism NOT evidence </li></ul>
  23. 23. Class I: Sodium Channel Blockers <ul><li>Decrease Na + movement in phases 0 and 4 </li></ul><ul><li>Decreases rate of propagation (conduction) via tissue with fast potential (Purkinje) </li></ul><ul><ul><li>Ignores those with slow potential (SA/AV) </li></ul></ul><ul><li>Indications: ventricular dysrhythmias </li></ul>
  24. 24. Class Ia Agents <ul><li>Slow conduction through ventricles </li></ul><ul><li>Decrease repolarization rate </li></ul><ul><ul><li>Widen QRS and QT intervals </li></ul></ul><ul><ul><ul><li>May promote Torsades des Pointes! </li></ul></ul></ul><ul><li>PDQ : </li></ul><ul><ul><li>procainamide (Pronestyl ® ) </li></ul></ul><ul><ul><li>disopyramide (Norpace ® ) </li></ul></ul><ul><ul><li>qunidine </li></ul></ul><ul><ul><li>(Quinidex ® ) </li></ul></ul>
  25. 25. Class Ib Agents <ul><li>Slow conduction through ventricles </li></ul><ul><li>Increase rate of repolarization </li></ul><ul><li>Reduce automaticity </li></ul><ul><ul><li>Effective for ectopic foci </li></ul></ul><ul><li>May have other uses </li></ul><ul><li>LTMD : </li></ul><ul><ul><li>l idocaine (Xylocaine ® ) </li></ul></ul><ul><ul><li>t ocainide (Tonocard ® ) </li></ul></ul><ul><ul><li>m exiletine (Mexitil ® ) </li></ul></ul><ul><ul><li>phenytoin ( D ilantin ® ) </li></ul></ul>
  26. 26. Class Ic Agents <ul><li>Slow conduction through ventricles, atria & conduction system </li></ul><ul><li>Decrease repolarization rate </li></ul><ul><li>Decrease contractility </li></ul><ul><li>Rare last chance drug </li></ul><ul><li>flecainide (Tambocor ® ) </li></ul><ul><li>propafenone (Rythmol ® ) </li></ul>
  27. 27. Class II: Beta Blockers <ul><li>Beta 1 receptors in heart attached to Ca ++ channels </li></ul><ul><ul><li>Gradual Ca ++ influx responsible for automaticity </li></ul></ul><ul><li>Beta 1 blockade decreases Ca ++ influx </li></ul><ul><ul><li>Effects similar to Class IV (Ca ++ channel blockers) </li></ul></ul><ul><li>Limited # approved for tachycardias </li></ul>
  28. 28. Class II: Beta Blockers <ul><li>propranolol (Inderal ® ) </li></ul><ul><li>acebutolol (Sectral ® ) </li></ul><ul><li>esmolol (Brevibloc ® ) </li></ul>
  29. 29. Class III: Potassium Channel Blockers <ul><li>Decreases K + efflux during repolarization </li></ul><ul><li>Prolongs repolarization </li></ul><ul><li>Extends effective refractory period </li></ul><ul><li>Prototype: bretyllium tosylate (Bretylol ® ) </li></ul><ul><ul><li>Initial norepi discharge may cause temporary hypertension/tachycardia </li></ul></ul><ul><ul><li>Subsequent norepi depletion may cause hypotension </li></ul></ul>
  30. 30. Class IV: Calcium Channel Blockers <ul><li>Similar effect as ß blockers </li></ul><ul><li>Decrease SA/AV automaticity </li></ul><ul><li>Decrease AV conductivity </li></ul><ul><li>Useful in breaking reentrant circuit </li></ul><ul><li>Prime side effect: hypotension & bradycardia </li></ul><ul><li>verapamil (Calan ® ) </li></ul><ul><li>diltiazem (Cardizem ® ) </li></ul><ul><li>Note: nifedipine doesn’t work on heart </li></ul>
  31. 31. Misc. Agents <ul><li>adenosine (Adenocard ® ) </li></ul><ul><ul><li>Decreases Ca ++ influx & increases K + efflux via 2 nd messenger pathway </li></ul></ul><ul><ul><ul><li>Hyperpolarization of membrane </li></ul></ul></ul><ul><ul><ul><li>Decreased conduction velocity via slow potentials </li></ul></ul></ul><ul><ul><ul><li>No effect on fast potentials </li></ul></ul></ul><ul><li>Profound side effects possible (but short-lived) </li></ul>
  32. 32. Misc. Agents <ul><li>Cardiac Glycocides </li></ul><ul><li>digoxin (Lanoxin ® ) </li></ul><ul><ul><li>Inhibits NaKATP pump </li></ul></ul><ul><ul><li>Increases intracellular Ca ++ </li></ul></ul><ul><ul><ul><li>via Na + -Ca ++ exchange pump </li></ul></ul></ul><ul><ul><li>Increases contractility </li></ul></ul><ul><ul><li>Decreases AV conduction velocity </li></ul></ul>
  33. 33. Pharmacology Antihypertensives
  34. 34. Antihypertensive Classes <ul><li>diuretics </li></ul><ul><li>beta blockers </li></ul><ul><li>angiotensin-converting enzyme (ACE) inhibitors </li></ul><ul><li>calcium channel blockers </li></ul><ul><li>vasodilators </li></ul>
  35. 35. Blood Pressure = CO X PVR <ul><li>Cardiac Output = SV x HR </li></ul><ul><li>PVR = Afterload </li></ul>
  36. 36. BP = CO x PVR Key: CCB = calcium channel blockers CA Adrenergics = central-acting adrenergics ACEi’s = angiotensin-converting enzyme inhibitors cardiac factors circulating volume heart rate contractility 1. Beta Blockers 2. CCB’s 3. C.A. Adrenergics salt aldosterone ACEi’s Diuretics
  37. 37. BP = CO x PVR Peripheral Sympathetic Receptors alpha beta 1. alpha blockers 2. beta blockers Local Acting 1. Peripheral-Acting Adrenergics Hormones 1. vasodilators 2. ACEI’s 3. CCB’s Central Nervous System 1. CA Adrenergics
  38. 38. Alpha 1 Blockers <ul><li>Stimulate alpha 1 receptors -> hypertension </li></ul><ul><li>Block alpha 1 receptors -> hypotension </li></ul><ul><li>doxazosin (Cardura ® ) </li></ul><ul><li>prazosin (Minipress ® ) </li></ul><ul><li>terazosin (Hytrin ® ) </li></ul>
  39. 39. Central Acting Adrenergics <ul><li>Stimulate alpha 2 receptors </li></ul><ul><ul><li>inhibit alpha 1 stimulation </li></ul></ul><ul><ul><ul><li>hypotension </li></ul></ul></ul><ul><li>clonidine (Catapress ® ) </li></ul><ul><li>methyldopa (Aldomet ® ) </li></ul>
  40. 40. Peripheral Acting Adrenergics <ul><li>reserpine (Serpalan ® ) </li></ul><ul><li>inhibits the release of NE </li></ul><ul><li>diminishes NE stores </li></ul><ul><li>leads to hypotension </li></ul><ul><li>Prominent side effect of depression </li></ul><ul><ul><li>also diminishes seratonin </li></ul></ul>
  41. 41. Adrenergic Side Effects <ul><li>Common </li></ul><ul><ul><li>dry mouth, drowsiness, sedation & constipation </li></ul></ul><ul><ul><li>orthostatic hypotension </li></ul></ul><ul><li>Less common </li></ul><ul><ul><li>headache, sleep disturbances, nausea, rash & palpitations </li></ul></ul>
  42. 42. ACE Inhibitors Angiotensin I ACE Angiotensin II 1. potent vasoconstrictor - increases BP 2. stimulates Aldosterone - Na + & H 2 O reabsorbtion . RAAS
  43. 43. Renin-Angiotensin Aldosterone System <ul><li>Angiotensin II = vasoconstrictor </li></ul><ul><li>Constricts blood vessels & increases BP </li></ul><ul><li>Increases SVR or afterload </li></ul><ul><li>ACE-I blocks these effects decreasing SVR & afterload </li></ul>
  44. 44. ACE Inhibitors <ul><li>Aldosterone secreted from adrenal glands cause sodium & water reabsorption </li></ul><ul><li>Increase blood volume </li></ul><ul><li>Increase preload </li></ul><ul><li>ACE-I blocks this and decreases preload </li></ul>
  45. 45. Angiotensin Converting Enzyme Inhibitors <ul><li>captopril (Capoten ® ) </li></ul><ul><li>enalapril (Vasotec ® ) </li></ul><ul><li>lisinopril (Prinivil ® & Zestril ® ) </li></ul><ul><li>quinapril (Accupril ® ) </li></ul><ul><li>ramipril (Altace ® ) </li></ul><ul><li>benazepril (Lotensin ® ) </li></ul><ul><li>fosinopril (Monopril ® ) </li></ul>
  46. 46. Calcium Channel Blockers <ul><li>Used for: </li></ul><ul><ul><li>Angina </li></ul></ul><ul><ul><li>Tachycardias </li></ul></ul><ul><ul><li>Hypertension </li></ul></ul>
  47. 47. CCB Site of Action diltiazem & verapamil nifedipine (and other dihydropyridines )
  48. 48. CCB Action <ul><li>diltiazem & verapamil </li></ul><ul><ul><li>decrease automaticity & conduction in SA & AV nodes </li></ul></ul><ul><ul><li>decrease myocardial contractility </li></ul></ul><ul><ul><li>decreased smooth muscle tone </li></ul></ul><ul><ul><li>decreased PVR </li></ul></ul><ul><li>nifedipine </li></ul><ul><ul><li>decreased smooth muscle tone </li></ul></ul><ul><ul><li>decreased PVR </li></ul></ul>
  49. 49. Side Effects of CCBs <ul><li>Cardiovascular </li></ul><ul><ul><li>hypotension, palpitations & tachycardia </li></ul></ul><ul><li>Gastrointestinal </li></ul><ul><ul><li>constipation & nausea </li></ul></ul><ul><li>Other </li></ul><ul><ul><li>rash, flushing & peripheral edema </li></ul></ul>
  50. 50. Calcium Channel Blockers <ul><li>diltiazem (Cardizem ® ) </li></ul><ul><li>verapamil (Calan ® , Isoptin ® ) </li></ul><ul><li>nifedipine (Procardia ® , Adalat ® ) </li></ul>
  51. 51. Diuretic Site of Action . loop of Henle proximal tubule Distal tubule Collecting duct
  52. 52. Mechanism <ul><li>Water follows Na + </li></ul><ul><li>20-25% of all Na + is reabsorbed into the blood stream in the loop of Henle </li></ul><ul><li>5-10% in distal tubule & 3% in collecting ducts </li></ul><ul><li>If it can not be absorbed it is excreted with the urine </li></ul><ul><li> Blood volume =  preload ! </li></ul>
  53. 53. Side Effects of Diuretics <ul><li>electrolyte losses [ Na + & K + ] </li></ul><ul><li>fluid losses [dehydration] </li></ul><ul><li>myalgia </li></ul><ul><li>N/V/D </li></ul><ul><li>dizziness </li></ul><ul><li>hyperglycemia </li></ul>
  54. 54. Diuretics <ul><li>Thiazides: </li></ul><ul><ul><li>chlorothiazide (Diuril ® ) & hydrochlorothiazide (HCTZ ® , HydroDIURIL ® ) </li></ul></ul><ul><li>Loop Diuretics </li></ul><ul><ul><li>furosemide (Lasix ® ), bumetanide (Bumex ® ) </li></ul></ul><ul><li>Potassium Sparing Diuretics </li></ul><ul><ul><li>spironolactone (Aldactone ® ) </li></ul></ul>
  55. 55. Mechanism of Vasodilators <ul><li>Directly relaxes arteriole smooth muscle </li></ul><ul><li>Decrease SVR = decrease afterload </li></ul>
  56. 56. Side Effects of Vasodilators <ul><li>hydralazine (Apresoline ® ) </li></ul><ul><ul><li>Reflex tachycardia </li></ul></ul><ul><li>sodium nitroprusside (Nipride ® ) </li></ul><ul><ul><li>Cyanide toxicity in renal failure </li></ul></ul><ul><ul><li>CNS toxicity = agitation, hallucinations, etc. </li></ul></ul>
  57. 57. Vasodilators <ul><li>diazoxide [Hyperstat ® ] </li></ul><ul><li>hydralazine [Apresoline ® ] </li></ul><ul><li>minoxidil [Loniten ® ] </li></ul><ul><li>sodium Nitroprusside [Nipride ® ] </li></ul>
  58. 58. Pharmacology Drugs Affecting Hemostasis
  59. 59. Hemostasis <ul><li>Reproduce figure 11-9, page 359 Sherwood </li></ul>
  60. 60. Platelet Adhesion
  61. 61. Coagulation Cascade <ul><li>Reproduce following components of cascade: </li></ul><ul><ul><li>Prothrombin -> thrombin </li></ul></ul><ul><ul><ul><li>Fibrinogen -> fibrin </li></ul></ul></ul><ul><ul><li>Plasminogen -> plasmin </li></ul></ul>
  62. 62. Platelet Inhibitors <ul><li>Inhibit the aggregation of platelets </li></ul><ul><li>Indicated in progressing MI, TIA/CVA </li></ul><ul><li>Side Effects: uncontrolled bleeding </li></ul><ul><li>No effect on existing thrombi </li></ul>
  63. 63. Aspirin <ul><ul><li>Inhibits COX </li></ul></ul><ul><ul><ul><li>Arachidonic acid (COX) -> TXA2 (  aggregation) </li></ul></ul></ul>
  64. 64. GP IIB/IIIA Inhibitors GP II b/ III a Inhibitors Fibrinogen GP II b/ III a Receptor
  65. 65. GP IIB/IIIA Inhibitors <ul><li>abciximab (ReoPro ® ) </li></ul><ul><li>eptifibitide (Integrilin ® ) </li></ul><ul><li>tirofiban (Aggrastat ® ) </li></ul>
  66. 66. Anticoagulants <ul><li>Interrupt clotting cascade at various points </li></ul><ul><ul><li>No effect on platelets </li></ul></ul><ul><li>Heparin & LMW Heparin (Lovenox ® ) </li></ul><ul><li>warfarin (Coumadin ® ) </li></ul>
  67. 67. Heparin <ul><li>Endogenous </li></ul><ul><ul><li>Released from mast cells/basophils </li></ul></ul><ul><li>Binds with antithrombin III </li></ul><ul><li>Antithrombin III binds with and inactivates excess thrombin to regionalize clotting activity. </li></ul><ul><ul><li>Most thrombin (80-95%) captured in fibrin mesh. </li></ul></ul><ul><li>Antithrombin-heparin complex 1000X as effective as antithrombin III alone </li></ul>
  68. 68. Heparin <ul><li>Measured in Units, not milligrams </li></ul><ul><li>Indications: </li></ul><ul><ul><li>MI, PE, DVT, ischemic CVA </li></ul></ul><ul><li>Antidote for heparin OD: protamine. </li></ul><ul><ul><li>MOA: heparin is strongly negatively charged. Protamine is strongly positively charged. </li></ul></ul>
  69. 69. warfarin (Coumadin ® ) <ul><li>Factors II, VII, IX and X all vitamin K dependent enzymes </li></ul><ul><li>Warfarin competes with vitamin K in the synthesis of these enzymes. </li></ul><ul><li>Depletes the reserves of clotting factors. </li></ul><ul><li>Delayed onset (~12 hours) due to existing factors </li></ul>
  70. 70. Thrombolytics <ul><li>Directly break up clots </li></ul><ul><ul><li>Promote natural thrombolysis </li></ul></ul><ul><li>Enhance activation of plasminogen </li></ul><ul><li>‘ Time is Muscle’ </li></ul><ul><li>streptokinase (Streptase ® ) </li></ul><ul><li>alteplase (tPA ® , Activase ® ) </li></ul><ul><li>anistreplase (Eminase ® ) </li></ul><ul><li>reteplase (Retevase ® ) </li></ul><ul><li>tenecteplase (TNKase ® ) </li></ul>
  71. 71. Occlusion Mechanism
  72. 72. tPA Mechanism
  73. 73. Cholesterol Metabolism <ul><li>Cholesterol important component in membranes and as hormone precursor </li></ul><ul><li>Synthesized in liver </li></ul><ul><ul><li>Hydroxymethylglutaryl coenzyme A reductase </li></ul></ul><ul><ul><li>( HMG CoA reductase ) dependant </li></ul></ul><ul><li>Stored in tissues for latter use </li></ul><ul><li>Insoluble in plasma (a type of lipid) </li></ul><ul><ul><li>Must have transport mechanism </li></ul></ul>
  74. 74. Lipoproteins <ul><li>Lipids are surrounded by protein coat to ‘hide’ hydrophobic fatty core. </li></ul><ul><li>Lipoproteins described by density </li></ul><ul><ul><li>VLDL, LDL, IDL, HDL, VHDL </li></ul></ul><ul><li>LDL contain most cholesterol in body </li></ul><ul><ul><li>Transport cholesterol from liver to tissues for use (“Bad”) </li></ul></ul><ul><li>HDL move cholesterol back to liver </li></ul><ul><ul><li>“ Good” b/c remove cholesterol from circulation </li></ul></ul>
  75. 75. Why We Fear Cholesterol <ul><li>Risk of CAD linked to LDL levels </li></ul><ul><li>LDLs are deposited under endothelial surface and oxidized where they: </li></ul><ul><ul><li>Attracts monocytes -> macrophages </li></ul></ul><ul><ul><li>Macrophages engulf oxidized LDL </li></ul></ul><ul><ul><ul><li>Vacuolation into ‘foam cells’ </li></ul></ul></ul><ul><ul><li>Foam cells protrude against intimal lining </li></ul></ul><ul><ul><ul><li>Eventually a tough cap is formed </li></ul></ul></ul><ul><ul><li>Vascular diameter & blood flow decreased </li></ul></ul>
  76. 76. Why We Fear Cholesterol <ul><li>Plaque cap can rupture </li></ul><ul><li>Collagen exposed </li></ul><ul><li>Clotting cascade activated </li></ul><ul><li>Platelet adhesion </li></ul><ul><li>Thrombus formation </li></ul><ul><li>Embolus formation possible </li></ul><ul><li>Occlusion causes ischemia </li></ul>
  77. 77. Lipid Deposition
  78. 78. Thrombus Formation
  79. 79. Platelet Adhesion
  80. 80. Embolus Formation
  81. 81. Occlusion Causes Infarction
  82. 82. Antihyperlipidemic Agents <ul><li>Goal: Decrease LDL </li></ul><ul><ul><li>Inhibition of LDL synthesis </li></ul></ul><ul><ul><li>Increase LDL receptors in liver </li></ul></ul><ul><li>Target: < 200 mg/dl </li></ul><ul><li>Statins are HMG CoA reductase inhibitors </li></ul><ul><li>lovastatin (Mevacor ® ) </li></ul><ul><li>pravastatin (Pravachol ® ) </li></ul><ul><li>simvastatin (Zocor ® ) </li></ul><ul><li>atorvastatin (Lipitor ® ) </li></ul>

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