Antianginal Agents. Antidysrythmic Agents. Coronary Ischemia: Supply and Demand Economics.
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Transcript of Antianginal Agents. Antidysrythmic Agents. Coronary Ischemia: Supply and Demand Economics.
Antianginal Antianginal AgentsAgents..
Antidysrythmic Antidysrythmic AgentsAgents
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.
Antianginal AgentsAntianginal Agents
NitratesNitrates Beta blockersBeta blockers Calcium channel blockersCalcium channel blockers
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: 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.
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
Antianginal Agents: Antianginal Agents: Beta BlockersBeta Blockers
Therapeutic UsesTherapeutic Uses AntianginalAntianginal AntihypertensiveAntihypertensive Cardioprotective effects, especially Cardioprotective effects, especially
after MIafter MI
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 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.
Antianginal Agents: Antianginal Agents: Nitroglycerin Nitroglycerin
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.
Antianginal Agents: Antianginal Agents: Nitroglycerin Nitroglycerin
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.
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
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 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