antianginal agents. coronary ischemia: supply and demand economics

Antianginal AgentsAntianginal Agents

Coronary Ischemia:Coronary Ischemia:

Supply and Demand Supply and Demand EconomicsEconomics

Coronary IschemiaCoronary Ischemia:: Supply and Demand Economics Supply and Demand Economics

The Grip of AnginaThe Grip of Angina

Supply-Demand Supply-Demand MismatchMismatch

Oxygen Supply -Blood Flow -O2 Carrying Capacity

Oxygen Demand -Heart rate -Contractility -Wall stress

Myocardial Oxygen Demand

Heart Rate

Contractility

Wall Stress

Adapted from Runge et al, Netter’s Cardiology

Determinants of Myocardial Determinants of Myocardial Oxygen SupplyOxygen Supply

Hgb

Oxygen Delivery

O2 Carrying Capacity

Coronary Blood Flow

Determinants of Myocardial Determinants of Myocardial Oxygen SupplyOxygen Supply

Perfusion Pressure

IInnttrriinnssiicc VVaassccuullaarr

RReessiissttaannccee

Extrinsic Compression

Coronary Blood Flow

O2 Carrying Capacity

Coronary Flow Coronary Flow ReserveReserve

Adapted from Maseri A, Ischemic Heart Disease, Churchill Livingstone, 1995

Angina Pectoris (Chest Angina Pectoris (Chest Pain)Pain) When the supply of oxygen and When the supply of oxygen and

nutrients in the blood is nutrients in the blood is insufficient to meet the demands insufficient to meet the demands of the heart, the heart muscle of the heart, the heart muscle achesaches..

The heart demands a large supply The heart demands a large supply of oxygen to meet the demands of oxygen to meet the demands placed on it.placed on it.

Types of AnginaTypes of Angina

Chronic stable angina Chronic stable angina (also called classic or effort angina)(also called classic or effort angina)

Unstable anginaUnstable angina(also called preinfarction or crescendo (also called preinfarction or crescendo angina)angina)

Vasospastic anginaVasospastic angina(also called Prinzmetal’s or variant (also called Prinzmetal’s or variant angina)angina)

Angina Drug TherapyAngina Drug Therapy

Antianginal AgentsAntianginal Agents

NitratesNitrates Beta blockersBeta blockers Calcium channel blockersCalcium channel blockers

Antianginal Agents:Antianginal Agents:

Therapeutic ObjectivesTherapeutic Objectives Increase blood flow to ischemic heart Increase blood flow to ischemic heart

musclemuscle

and/orand/or Decrease myocardial oxygen demandDecrease myocardial oxygen demand

Antianginal Agents:Antianginal Agents:

Therapeutic ObjectivesTherapeutic Objectives Minimize the frequency of attacks and Minimize the frequency of attacks and

decrease the duration and intensity of decrease the duration and intensity of anginal painanginal pain

Improve the patient’s functional Improve the patient’s functional capacity with as few side effects as capacity with as few side effects as possiblepossible

Prevent or delay the worst possible Prevent or delay the worst possible outcome, MIoutcome, MI

Nitric OxideNitric Oxide

Opie LH: Heart Physiology Lippincot Williams & Wilkins, 2004

Antianginal Agents: Antianginal Agents: NitratesNitrates

Available forms:Available forms:SublingualSublingual OintmentsOintments

BuccalBuccal Transdermal Transdermal patchespatches

Chewable tabletsChewable tablets Inhalable spraysInhalable sprays

CapsulesCapsules Intravenous Intravenous solutionssolutions

Antianginal Agents: Antianginal Agents: NitratesNitrates Cause vasodilation due to Cause vasodilation due to

relaxation of smooth musclesrelaxation of smooth muscles

Potent dilating effect on coronary Potent dilating effect on coronary arteriesarteries

Used for prophylaxis and treatment Used for prophylaxis and treatment

of anginaof angina

Antianginal Agents: Antianginal Agents: Nitrates Nitrates

NitroglycerinNitroglycerin Prototypical nitratePrototypical nitrate Large first-pass effect with PO formsLarge first-pass effect with PO forms Used for symptomatic treatment of Used for symptomatic treatment of

ischemic heart conditions (angina)ischemic heart conditions (angina) IV form used for BP control in IV form used for BP control in

perioperative hypertension, treatment perioperative hypertension, treatment of CHF, ischemic pain,of CHF, ischemic pain, and pulmonary and pulmonary edema associated with acute MIedema associated with acute MI

Antianginal Agents: Antianginal Agents: Nitrates Nitrates isosorbide dinitrate isosorbide dinitrate

(Isordil, Sorbitrate, Dilatrate SR)(Isordil, Sorbitrate, Dilatrate SR) isosorbide mononitrate isosorbide mononitrate

(Imdur, Monoket, ISMO)(Imdur, Monoket, ISMO)

Used for:Used for: Acute relief of anginaAcute relief of angina Prophylaxis in situations that may Prophylaxis in situations that may

provoke anginaprovoke angina Long-term prophylaxis of anginaLong-term prophylaxis of angina

Antianginal Agents: Antianginal Agents: Nitrates Nitrates

Side EffectsSide Effects HeadacheHeadache

– Usually diminish in intensity and Usually diminish in intensity and frequency frequency with continued usewith continued use

Tachycardia, postural hypotensionTachycardia, postural hypotension Tolerance may developTolerance may develop

Nitrate ToleranceNitrate Tolerance

Occurs with chronic administration Occurs with chronic administration of long acting nitrates.of long acting nitrates.

Efficacy of drug diminishes with Efficacy of drug diminishes with chronic exposure (tachyphylaxis).chronic exposure (tachyphylaxis).

Tolerance readily reverses with Tolerance readily reverses with nitrate free interval.nitrate free interval.

Antianginal Agents: Antianginal Agents: Beta BlockersBeta Blockers atenolol (Tenormin)atenolol (Tenormin) metoprolol (Lopressor)metoprolol (Lopressor) propranolol (Inderal)propranolol (Inderal) nadolol (Corgard)nadolol (Corgard)

Adrenergic ReceptorsAdrenergic ReceptorsBetaBeta11 SA node, AV node, His-Purkinje SA node, AV node, His-Purkinje

systemsystem MyocardiumMyocardium Juxtaglomerular apparatusJuxtaglomerular apparatus AdipocytesAdipocytes

BetaBeta22 Peripheral and coronary vasculaturePeripheral and coronary vasculature BronchiBronchi Peripheral MusclePeripheral Muscle Uterine MuscleUterine Muscle

AlphaAlpha Peripheral circulationPeripheral circulation

Adapted from Runge et al, Netter’s Cardiology

Beta-1

Beta-2

Alpha

Antianginal Agents: Antianginal Agents: Beta BlockersBeta Blockers

Mechanism of ActionMechanism of Action Decrease the HR, resulting in Decrease the HR, resulting in

decreased myocardial oxygen demand decreased myocardial oxygen demand and increased oxygen delivery to the and increased oxygen delivery to the heartheart

Decrease myocardial contractility, Decrease myocardial contractility, helping to conserve energy or helping to conserve energy or decrease demanddecrease demand


Therapeutic UsesTherapeutic Uses AntianginalAntianginal AntihypertensiveAntihypertensive Cardioprotective effects, especially Cardioprotective effects, especially

after MIafter MI


Side EffectsSide Effects

Body SystemBody System EffectsEffectsCardiovascularCardiovascular bradycardia, hypotensionbradycardia, hypotension

second- or third-degree second- or third-degree heart blockheart block

heart failureheart failure

MetabolicMetabolic Altered glucose and lipidAltered glucose and lipidmetabolismmetabolism


Side EffectsSide Effects

Body SystemBody System EffectsEffectsCNSCNS dizziness, fatigue, dizziness, fatigue, mental depression, lethargy,mental depression, lethargy,drowsiness, unusual dreamsdrowsiness, unusual dreams

OtherOther impotenceimpotencewheezing, dyspneawheezing, dyspnea

Antianginal Agents: Antianginal Agents: Calcium Channel Calcium Channel BlockersBlockers verapamil (Calan)verapamil (Calan) diltiazem (Cardizem)diltiazem (Cardizem) nifedipine (Procardia)nifedipine (Procardia)

Role of Calcium Channels in Role of Calcium Channels in Myocardial ContractionMyocardial Contraction

Opie LH, Heart Physiology, Williams Lippincott and Williams 2004

Role of Calcium Channel in Vascular Role of Calcium Channel in Vascular Smooth Muscle FunctionSmooth Muscle Function

Opie LH, Heart Physiology, Williams Lippincott and Williams 2004

Antianginal Agents: Antianginal Agents: Calcium Channel Calcium Channel BlockersBlockersMechanism of ActionMechanism of Action Cause peripheral arterial vasodilationCause peripheral arterial vasodilation Reduce myocardial contractility Reduce myocardial contractility

(negative inotropic action)(negative inotropic action) Result: decreased myocardial oxygen Result: decreased myocardial oxygen

demanddemand

Antianginal Agents: Antianginal Agents: Calcium Channel Calcium Channel BlockersBlockersTherapeutic UsesTherapeutic Uses First-line agents for treatment of First-line agents for treatment of

angina, hypertension, and angina, hypertension, and supraventricular tachycardiasupraventricular tachycardia

Short-term management of atrial Short-term management of atrial fibrillation and flutterfibrillation and flutter

Several other usesSeveral other uses

Antianginal Agents: Antianginal Agents: Calcium Channel Calcium Channel BlockersBlockersSide EffectsSide Effects Very acceptable side effect and safety Very acceptable side effect and safety

profileprofile May cause hypotension, palpitations, May cause hypotension, palpitations,

tachycardia tachycardia or bradycardia, constipation, nausea, or bradycardia, constipation, nausea, dyspneadyspnea

Treatment of Ischemic Treatment of Ischemic Heart DiseaseHeart Disease

Antianginal Agents: Antianginal Agents: Nursing ImplicationsNursing Implications Before administering, perform a Before administering, perform a

complete health history to determine complete health history to determine presence of conditions that may be presence of conditions that may be contraindications contraindications for use or call for cautious use.for use or call for cautious use.

Obtain baseline VS, including Obtain baseline VS, including respiratory patterns and rate.respiratory patterns and rate.

Assess for drug interactions.Assess for drug interactions.

Antianginal Agents: Antianginal Agents: Nursing ImplicationsNursing Implications Patients should not take any Patients should not take any

medications, including OTC medications, medications, including OTC medications, without checking with the physician.without checking with the physician.

Patients should report blurred vision, Patients should report blurred vision, persistent headache, dry mouth, persistent headache, dry mouth, dizziness, edema, fainting episodes, dizziness, edema, fainting episodes, weight gain of 2 pounds in 1 day or 5 or weight gain of 2 pounds in 1 day or 5 or more pounds in 1 week, pulse rates more pounds in 1 week, pulse rates under 60, and any dyspnea.under 60, and any dyspnea.

Antianginal Agents: Antianginal Agents: Nursing ImplicationsNursing Implications Alcohol consumption and hot baths or Alcohol consumption and hot baths or

spendingspending time in jacuzzis, hot tubs, or time in jacuzzis, hot tubs, or saunas will result in vasodilation, saunas will result in vasodilation, hypotension, and the possibility of fainting.hypotension, and the possibility of fainting.

Teach patients to change positions slowly Teach patients to change positions slowly to avoid postural BP changes.to avoid postural BP changes.

Encourage patients to keep a record of Encourage patients to keep a record of their anginal attacks, including their anginal attacks, including precipitating factors, number of pills taken, precipitating factors, number of pills taken, and therapeutic effects.and therapeutic effects.

Antianginal Agents: Antianginal Agents: NitroglycerinNitroglycerin

Nursing ImplicationsNursing Implications Instruct patients in proper technique and Instruct patients in proper technique and

guidelines for taking sublingual NTG for anginal guidelines for taking sublingual NTG for anginal pain.pain.

Instruct patients never to chew or swallow the SL Instruct patients never to chew or swallow the SL form.form.

Instruct patients that a burning sensation felt with Instruct patients that a burning sensation felt with SL forms indicates that the drug is still potent.SL forms indicates that the drug is still potent.

Antianginal Agents: Antianginal Agents:

NitroglycerinNitroglycerin Nursing ImplicationsNursing Implications Patients are taught to take up to three tablets every 5 Patients are taught to take up to three tablets every 5

minutes. If no relief from chest pain is obtained after minutes. If no relief from chest pain is obtained after three tablets, they should seek medical assistance.three tablets, they should seek medical assistance.

Absorption nitroglycerin ointments best over a nonfatty Absorption nitroglycerin ointments best over a nonfatty and nonhairy portion of skin. The upper torso is the and nonhairy portion of skin. The upper torso is the preferred site of application. The nurse should wear preferred site of application. The nurse should wear gloves when applying to prevent transdermal absorption gloves when applying to prevent transdermal absorption by the applier. The ointment is measured as one straight by the applier. The ointment is measured as one straight line on the nitroglycerin patch and is gently spread over line on the nitroglycerin patch and is gently spread over paper and applied, but not rubbed, into the skin. paper and applied, but not rubbed, into the skin.

Antianginal Agents: Antianginal Agents: Nitroglycerin Nitroglycerin

Nursing ImplicationsNursing Implications Instruct patients to keep a fresh supply Instruct patients to keep a fresh supply

of NTG on hand; potency is lost in of NTG on hand; potency is lost in about 3 months after the bottle has about 3 months after the bottle has been opened.been opened.

Medications should be stored in an Medications should be stored in an airtight, dark glass bottle with a metal airtight, dark glass bottle with a metal cap and no cotton filler to preserve cap and no cotton filler to preserve potency.potency.


Nursing ImplicationsNursing Implications Instruct patients in the proper application Instruct patients in the proper application

of nitrate topical ointments and of nitrate topical ointments and transdermal forms, including site rotation transdermal forms, including site rotation and removal of old medication.and removal of old medication.

To reduce tolerance, the patient may be To reduce tolerance, the patient may be instructed to remove topical forms at instructed to remove topical forms at bedtime, and apply new doses in the bedtime, and apply new doses in the morning, allowing for a nitrate-free period.morning, allowing for a nitrate-free period.

Antianginal Agents: Antianginal Agents: NitroglycerinNitroglycerin

Nursing ImplicationsNursing Implications Instruct patients to take prn nitrates at the Instruct patients to take prn nitrates at the

first hint of anginal pain.first hint of anginal pain. If experiencing chest pain, the patient If experiencing chest pain, the patient

taking SL NTG should be lying down to taking SL NTG should be lying down to prevent or decrease dizziness and fainting prevent or decrease dizziness and fainting that may occur due to hypotension.that may occur due to hypotension.

Monitor VS frequently during acuteMonitor VS frequently during acute exacerbations of angina and during IV exacerbations of angina and during IV administration.administration.


Nursing ImplicationsNursing Implications IV forms of NTG must be contained in glass IV IV forms of NTG must be contained in glass IV

bottles and must be given with infusion bottles and must be given with infusion pumps.pumps.

Discard parenteral solution that is blue, green, Discard parenteral solution that is blue, green, or dark red.or dark red.

Follow specific manufacturer’s instructions for Follow specific manufacturer’s instructions for IV administration. Use special IV tubing IV administration. Use special IV tubing provided or non-PVC tubing.provided or non-PVC tubing.

Antianginal Agents: Antianginal Agents: Calcium Channel Calcium Channel Blockers Blockers Nursing ImplicationsNursing Implications Blood levels should be monitored to Blood levels should be monitored to

ensure they ensure they are therapeutic.are therapeutic.

Oral CCBs should be taken before Oral CCBs should be taken before meals and meals and as ordered.as ordered.

Patients should be encouraged to limit Patients should be encouraged to limit caffeine intake.caffeine intake.

Antianginal Agents: Antianginal Agents: Beta Blockers Beta Blockers

Nursing ImplicationsNursing Implications Patients taking beta blockers should Patients taking beta blockers should

monitor pulse rate daily and report any monitor pulse rate daily and report any rate lower than 60 beats per minute.rate lower than 60 beats per minute.

Dizziness or fainting should also be Dizziness or fainting should also be reported.reported.

Constipation is a common problem. Constipation is a common problem. Instruct patients to take in adequate Instruct patients to take in adequate fluids and eat high-fiber foods.fluids and eat high-fiber foods.

Antianginal Agents: Antianginal Agents: Beta Blockers Beta Blockers

Nursing ImplicationsNursing Implications These medications should never be These medications should never be

abruptly discontinued due to risk of abruptly discontinued due to risk of rebound hypertensive crisis.rebound hypertensive crisis.

Inform patients that these medications Inform patients that these medications are for are for long-term prevention of angina, not for long-term prevention of angina, not for

immediate relief.immediate relief.

Antianginal Agents: Antianginal Agents: Nursing ImplicationsNursing Implications Monitor for adverse reactionsMonitor for adverse reactions

– Allergic reactions, headache, light-Allergic reactions, headache, light-headedness, hypotension, dizzinessheadedness, hypotension, dizziness

Monitor for therapeutic effectsMonitor for therapeutic effects– Relief of angina, decreased BP, or Relief of angina, decreased BP, or

bothboth

Antidysrhythmic Antidysrhythmic AgentsAgents

AntidysrhythmicsAntidysrhythmics

DysrhythmiaDysrhythmia Any deviation from the normal rhythm Any deviation from the normal rhythm

of the heartof the heart

AntidysrhythmicsAntidysrhythmics Drugs used for the treatment and Drugs used for the treatment and

prevention of disturbances in cardiac prevention of disturbances in cardiac rhythmrhythm

Cardiac CellCardiac Cell

Inside the cardiac cell, there Inside the cardiac cell, there exists a net negative charge exists a net negative charge relative to the outside of relative to the outside of the cell.the cell.

Resting Membrane Resting Membrane Potential: RMPPotential: RMP This difference in the electronegative This difference in the electronegative

charge.charge. Results from an uneven distribution of Results from an uneven distribution of

ions (sodium, potassium, calcium) ions (sodium, potassium, calcium) across the cell membrane.across the cell membrane.

An energy-requiring pump is needed to An energy-requiring pump is needed to maintain this uneven distribution of maintain this uneven distribution of ions.ions.

Sodium-potassium ATPase pumpSodium-potassium ATPase pump

Heart and Conduction SystemHeart and Conduction System

Resting Membrane Resting Membrane Potential Potential

of a Cardiac Cellof a Cardiac Cell

Abnormal Heart Abnormal Heart RhythmsRhythms

Arrhythmia BPM

tachycardia 150-250

bradycardia <60

atrial flutter 200-350

atrial fibrilation >350

prem. atrial cont. variable

prem. vent. cont. variable

vent. fibrilation variable

Premature Premature Ventricular Ventricular ContractioContractionn

Action PotentialAction Potential A change in the distribution of ions A change in the distribution of ions

causes cardiac cells to become excited.causes cardiac cells to become excited.

The movement of ions across the The movement of ions across the cardiac cell’s membrane results in the cardiac cell’s membrane results in the propagation propagation of an electrical impulse.of an electrical impulse.

This electrical impulse leads to This electrical impulse leads to contraction contraction of the myocardial muscle.of the myocardial muscle.

Action PotentialAction Potential

Four PhasesFour Phases The SA node and the Purkinje cells The SA node and the Purkinje cells

each have separate action potentials.each have separate action potentials.

Action Potentials: Phases Action Potentials: Phases (SA Node)(SA Node)

Action Potentials: Action Potentials: Purkinje FiberPurkinje Fiber

Action Potentials: IntervalsAction Potentials: Intervals

Abnormal Heart Abnormal Heart RhythmsRhythms Caused by:Caused by:

– ischemia, infarction, alteration of ischemia, infarction, alteration of body chemicalsbody chemicals

Symptoms:Symptoms:– palpitations, syncope, palpitations, syncope,

lightheadedness, visual lightheadedness, visual disturbances, pallor, cyanosis, disturbances, pallor, cyanosis, weakness, sweating, chest pain, weakness, sweating, chest pain, hypotensionhypotension

Pharmaceutical Pharmaceutical TreatmentTreatment Aimed at preventing life-Aimed at preventing life-

threatening conditions by threatening conditions by restoring normal rhythmrestoring normal rhythm

Acts on the myocardium where Acts on the myocardium where the impulses are conductedthe impulses are conducted

Some drugs influence heart rate, Some drugs influence heart rate, others influence movement of others influence movement of ions (Na and Ca)ions (Na and Ca)

Vaughan Williams Vaughan Williams ClassificationClassification System commonly used to System commonly used to

classify antidysrhythmic drugsclassify antidysrhythmic drugs

Vaughan Williams Vaughan Williams ClassificationClassification Class 1Class 1

– Class IaClass Ia– Class IbClass Ib– Class IcClass Ic

Class IIClass II Class IIIClass III Class IVClass IV OtherOther

Vaughan Williams Vaughan Williams ClassificationClassification

Class IClass I Membrane-stabilizing agentsMembrane-stabilizing agents Fast sodium channel blockersFast sodium channel blockers Divided into Ia, Ib, and Ic agents, Divided into Ia, Ib, and Ic agents,

according according to effectsto effects


Class IClass I

moricizinemoricizine General Class I agentGeneral Class I agent Has characteristics of all three Has characteristics of all three

subclassessubclasses Used for symptomatic ventricular and Used for symptomatic ventricular and

life-threatening dysrhythmiaslife-threatening dysrhythmias


Class IaClass Ia

quinidine, procainamide, disopyramidequinidine, procainamide, disopyramide Block sodium channelsBlock sodium channels Delay repolarizationDelay repolarization Increase the APDIncrease the APD Used for atrial fibrillation, premature atrial Used for atrial fibrillation, premature atrial

contractions, premature ventricular contractions, premature ventricular contractions, ventricular tachycardia, Wolff-contractions, ventricular tachycardia, Wolff-Parkinson-White syndromeParkinson-White syndrome


Class IbClass Ib

tocainide, mexiletine, phenytoin, lidocainetocainide, mexiletine, phenytoin, lidocaine Block sodium channelsBlock sodium channels Accelerate repolarizationAccelerate repolarization Decrease the APDDecrease the APD Used for ventricular dysrhythmias only Used for ventricular dysrhythmias only

(premature ventricular contractions, (premature ventricular contractions, ventricular tachycardia, ventricular fibrillation)ventricular tachycardia, ventricular fibrillation)


Class IcClass Ic

encainide, flecainide, propafenone encainide, flecainide, propafenone Block sodium channels (more Block sodium channels (more

pronounced effect)pronounced effect) Little effect on APD or repolarizationLittle effect on APD or repolarization Used for severe ventricular dysrhythmiasUsed for severe ventricular dysrhythmias May be used in atrial fibrillation/flutterMay be used in atrial fibrillation/flutter


Class IIClass II

Beta blockers: atenolol, esmolol, Beta blockers: atenolol, esmolol, petaprolol, propranolol petaprolol, propranolol

Reduce or block sympathetic nervous system Reduce or block sympathetic nervous system stimulation, thus reducing transmission of stimulation, thus reducing transmission of impulses in the heart’s conduction systemimpulses in the heart’s conduction system

Depress phase 4 depolarizationDepress phase 4 depolarization General myocardial depressants for both General myocardial depressants for both

supraventricular and ventricular supraventricular and ventricular dysrhythmiasdysrhythmias

Vaughan Williams ClassificationVaughan Williams Classification

Class IIIClass III amiodarone, bretylium, sotalol, ibutilide amiodarone, bretylium, sotalol, ibutilide Increase APDIncrease APD Prolong repolarization in phase 3Prolong repolarization in phase 3 Used for dysrhythmias that are difficult to treatUsed for dysrhythmias that are difficult to treat Life-threatening ventricular tachycardia or Life-threatening ventricular tachycardia or

fibrillation, atrial fibrillation or flutter—resistant to fibrillation, atrial fibrillation or flutter—resistant to other drugsother drugs

Sustained ventricular tachycardiaSustained ventricular tachycardia Ibutilide is specifically indicated only for treatment of recent-onset atrial Ibutilide is specifically indicated only for treatment of recent-onset atrial

fibrillation and flutter.fibrillation and flutter.

Patients taking amiodarone must have baseline and serial Patients taking amiodarone must have baseline and serial pulmonary function tests in order to monitor for potential pulmonary function tests in order to monitor for potential pulmonary toxicity.pulmonary toxicity.


Class IVClass IV

verapamil, diltiazem verapamil, diltiazem Calcium channel blockersCalcium channel blockers Depress phase 4 depolarizationDepress phase 4 depolarization Used for paroxysmal supraventricular Used for paroxysmal supraventricular

tachycardia; rate control for atrial tachycardia; rate control for atrial fibrillation and flutterfibrillation and flutter


Other AntidysrhythmicsOther Antidysrhythmics

digoxin, adenosine digoxin, adenosine Have properties of several classes and Have properties of several classes and

are not placed into one particular classare not placed into one particular class

AntidysrhythmicsAntidysrhythmicsDigoxinDigoxin Cardiac glycosideCardiac glycoside

Inhibits the sodium-potassium ATPase pumpInhibits the sodium-potassium ATPase pump

Positive inotrope—improves the strength of Positive inotrope—improves the strength of cardiac contractioncardiac contraction

Allows more calcium to be available for Allows more calcium to be available for contractioncontraction

Used for CHF and atrial dysrhythmiasUsed for CHF and atrial dysrhythmias

Monitor potassium levels, drug levels, and Monitor potassium levels, drug levels, and for toxicityfor toxicity

AntidysrhythmicsAntidysrhythmics

adenosine (Adenocard)adenosine (Adenocard) Slows conduction through the AV nodeSlows conduction through the AV node Used to convert paroxysmal Used to convert paroxysmal

supraventricular tachycardia to sinus supraventricular tachycardia to sinus rhythmrhythm

Very short half-lifeVery short half-life Only administered as fast IV pushOnly administered as fast IV push May cause asystole for a few secondsMay cause asystole for a few seconds Other side effects minimalOther side effects minimal

Antidysrhythmics: Antidysrhythmics: Side EffectsSide Effects

ALL antidysrhythmics can cause ALL antidysrhythmics can cause dysrhythmias!!dysrhythmias!!

Hypersensitivity reactionsHypersensitivity reactions– NauseaNausea– VomitingVomiting– DiarrheaDiarrhea– DizzinessDizziness– Blurred visionBlurred vision– HeadacheHeadache

Antidysrhythmics: Antidysrhythmics: Nursing ImplicationsNursing Implications Obtain a thorough drug and Obtain a thorough drug and

medical history.medical history. Measure baseline BP, P, and Measure baseline BP, P, and

cardiac rhythm.cardiac rhythm. Measure serum potassium levels Measure serum potassium levels

before initiating therapy.before initiating therapy.

Antidysrhythmics: Antidysrhythmics: Nursing ImplicationsNursing Implications Assess for conditions that may be Assess for conditions that may be

contraindications for use of contraindications for use of specific agents.specific agents.

Assess for potential drug Assess for potential drug interactions.interactions.

Instruct patients regarding dosing Instruct patients regarding dosing schedules and side effects to schedules and side effects to report to physician.report to physician.

Antidysrhythmics: Antidysrhythmics: Nursing ImplicationsNursing Implications During therapy, monitor cardiac During therapy, monitor cardiac

rhythm, heart rate, BP, general rhythm, heart rate, BP, general well-being, skin color, well-being, skin color, temperature, heart and breath temperature, heart and breath sounds.sounds.

Assess plasma drug levels as Assess plasma drug levels as indicated.indicated.

Monitor for toxic effects.Monitor for toxic effects.

Antidysrhythmics: Antidysrhythmics: Nursing ImplicationsNursing Implications Instruct patients to take medications Instruct patients to take medications

as scheduled and not to skip doses or as scheduled and not to skip doses or double up for missed doses.double up for missed doses.

Patients who miss a dose should Patients who miss a dose should contact their physician for instructions contact their physician for instructions if a dose is missed.if a dose is missed.

Instruct patients not to crush or chew Instruct patients not to crush or chew any oral sustained-release any oral sustained-release preparations.preparations.

Antidysrhythmics: Antidysrhythmics: Nursing ImplicationsNursing Implications For class I agents, monitor ECG For class I agents, monitor ECG

for QT intervals prolonged more for QT intervals prolonged more than 50%.than 50%.

IV infusions should be IV infusions should be administered with administered with an IV pump.an IV pump.

Antidysrhythmics: Antidysrhythmics: Nursing ImplicationsNursing Implications Patients taking propranolol, Patients taking propranolol,

digoxin, and other agents should digoxin, and other agents should be taught how to take their own be taught how to take their own radial pulse for 1 full minute, and radial pulse for 1 full minute, and to notify their physician if the to notify their physician if the pulse is less than 60 beats/minute pulse is less than 60 beats/minute before taking the next dose of before taking the next dose of medication.medication.

Antidysrhythmics: Antidysrhythmics: Nursing ImplicationsNursing Implications Monitor for therapeutic response:Monitor for therapeutic response:

– Decreased BP in hypertensive Decreased BP in hypertensive patientspatients

– Decreased edemaDecreased edema– Regular pulse rate orRegular pulse rate or– Pulse rate without major Pulse rate without major

irregularities, orirregularities, or– Improved regularity of rhythmImproved regularity of rhythm

antianginal agents. coronary ischemia: supply and demand economics

Documents

ischemic heart disease

large supply of oxygen

acute miantianginal

heart muscle aches

ischemic pain

runge et

treatment of chf

effort anginaunstable