drugs affecting the cardiovascular system. cardiovascular system z muscular organ with 4 chambers z...
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Drugs Affecting the Drugs Affecting the Cardiovascular SystemCardiovascular System
Cardiovascular System Cardiovascular System
Muscular organ with 4 chambersMuscular organ with 4 chambersPumps 5-6 liters blood/minutePumps 5-6 liters blood/minute
Chambers of the HeartChambers of the Heart
Left SideLeft SideOxygenatedOxygenated Pulmonary Pulmonary
veinsveinsAtriumAtriumMitral valveMitral valveVentricleVentricle
Right SideRight Side Unoxygenated Unoxygenated AtriumAtriumTricuspid valveTricuspid valveVentricleVentriclePulmonary Pulmonary
arteriesarteries
Systole and DiastoleSystole and Diastole
Systole: Heart is contractingSystole: Heart is contracting Diastole: Heart is relaxedDiastole: Heart is relaxed
Renin-Angiotensin-AldosteroneRenin-Angiotensin-Aldosterone
Renal blood flow decreasedRenal blood flow decreasedSympathetic stimulation causes Sympathetic stimulation causes
release of reninrelease of reninRenin + plasma angiotensin Renin + plasma angiotensin
forms angiotensin Iforms angiotensin IAngiotensin I converted in lungs Angiotensin I converted in lungs
to angiotensin IIto angiotensin II
Renin-Angiotensin-AldosteroneRenin-Angiotensin-AldosteroneContinuedContinued
Agniotensin II: Agniotensin II: Produces vasoconstriction Produces vasoconstriction Acts directly on kidney to retain Acts directly on kidney to retain sodium & water sodium & water Stimulates adrenal cortex to Stimulates adrenal cortex to secrete aldosteronesecrete aldosterone
Cardiotonic-Inotropic EffectsCardiotonic-Inotropic Effects
Increase force of myocardial Increase force of myocardial contractioncontraction
Causes improved heart’s Causes improved heart’s pumping abilitypumping ability
Cardiotonic-Inotropic DrugsCardiotonic-Inotropic Drugs
AdrenergicAdrenergic Digitalis glycosidesDigitalis glycosides AmrinoneAmrinone MilrinoneMilrinone
Inotropic DefinitionInotropic Definition
Force of myocardial contractionForce of myocardial contractionPositive inotropic drug: Positive inotropic drug:
increases force of contractionsincreases force of contractionsNegative inotropic drug: Negative inotropic drug:
decreases force of contractiondecreases force of contraction
Digitalis GlycosidesDigitalis Glycosides
Increase myocardial contractility Increase myocardial contractility causing more complete causing more complete emptyingemptying
Digitalis GlycosidesDigitalis Glycosides
DigitoxinDigitoxin
Absorption:Absorption:
90-100% Oral90-100% Oral
DigoxinDigoxin
Absorption:Absorption:
60-80% Tablet60-80% Tablet
90-100% Capsule90-100% Capsule
70-85% Elixir70-85% Elixir
Digitalis Glycosides Digitalis Glycosides ContinuedContinued
DigitoxinDigitoxin
Distribution:Distribution:
To most body To most body tissuestissues
90% bound to 90% bound to albuminalbumin
DigoxinDigoxin
Distribution:Distribution:
Throughout the Throughout the bodybody
Binds to skeletal Binds to skeletal muscle/20-30% muscle/20-30% to albuminto albumin
Digitalis Glycosides Digitalis Glycosides ContinuedContinued
DigitoxinDigitoxin
Metabolism:Metabolism:
Liver - 8% Liver - 8% converted to converted to digoxindigoxin
Excretion:Excretion:
KidneysKidneys
DigoxinDigoxin
Metabolism:Metabolism:
Small amount in Small amount in liver & GI floraliver & GI flora
Excretion:Excretion:
Unchanged drug Unchanged drug from kidneysfrom kidneys
Antianginal DrugsAntianginal Drugs
Organic nitrates: produce Organic nitrates: produce vasodilationvasodilation
Beta-adrenergic blocking drugs: Beta-adrenergic blocking drugs: Inhibits sympathetic stimulationInhibits sympathetic stimulation
Calcium-channel blockers: Calcium-channel blockers: Prevents Ca moving into cellsPrevents Ca moving into cells
Antihypertensive DrugsAntihypertensive Drugs
DiureticsDiureticsAntiadrenergicsAntiadrenergicsACE inhibitors ACE inhibitors Calcium-channel blockersCalcium-channel blockers
Hypotension and ShockHypotension and Shock
Alpha-adrenergic drugs: Alpha-adrenergic drugs: increase peripheral vascular increase peripheral vascular resistanceresistance
Beta-adrenergic drugs: increase Beta-adrenergic drugs: increase myocardial contractility & heart myocardial contractility & heart raterate