Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/74

Click to flip

74 Cards in this Set

  • Front
  • Back
What happens during depolarization?
Na+ rushes into the cell and increases membrane potential
What happens during the plateau phase?
Ca entry into the cell
Third dummy question
Third dummy answer
What is the definition of a proarrhythmic event?
• new type of arrhythmia • worsening of an arrhythmia • worsening due to starting an antiarrhythmic
What is defibrillation threshold?
energy requirement necessary for defibrillation of a ventricular arrhythmia into sinus rhythm
List 3 drugs that increase defibrillation threshold
• Amiodarone • Lidocaine • Mexiletine
Name a medication that lowers defibrillation threshold
Sotalol (a beta-blocker that is used for its antiarrhythmic effects, not its beta-blocking effects)
What is the goal for patients with A Fib?
• rate control is the goal • HR < 80 at rest & < 110 during activity
What are rate control meds used in A Fib?
• beta-blockers: which control HR at rest & during exercise • calcium channel bockers: preferred in COPD, avoid in CHF • Digoxin: controls HR at rest
What beta blockers should be avoid in treatment of A Fib?
• avoid pindolol & acetobutolol, due to their ISA activity
What happens if you a patient a calcium channel blocker & digoxin at the same time?
the patient can develop a "stone heart"
What can be done to control the rhythm in patients with A Fib?
• Direct current cardiversion (DCC) if duration of A Fib is less than 48 hrs. • Heparin should be initiated prior to DCC
What are complications of DCC?
• bradycardia • proarrhythmic events • skin burns • thrombus formation
How should you control A fib if onset is greater than 48 hours?
• Check TEE for thrombus, add heparin & perform DCC • if stable, initiate rate control and start warfarin (with a INR goal 2-3) for 3-4 weeks prior to DCC
What are the 3 classes of Na channel blockers?
I-A, I-B, I-C
What are the effects of Na channel blockers?
slows depolarization
List 3 Na channel blockers (Class I-A) drugs
• Disopyramide • Quinidine • Procainamide
Name Na channel blockers (class I-B) drugs
• Lidocaine • Mexiletene
Name Na channel blocker (class I-C) drugs
• Flecainide • Moricizine • Propafenone
What are EKG effects from Na Channel blockers (class I-A)?
increased QRS, increased QT (?)
What are EKG effects from Na Channel blockers (class I-B)?
increased QRS, decreased QT
What are EKG effects from Na Channel blockers (Class I-C)?
increase QRS interval
Describe the Class II antiarrhythmics
• beta blockers • metoprolol, esmolol, atenolol • increases PR interval • slows AV nodal conduction
Name the class III antiarrhythmics
• K channel blockers • Amiodarone, Dofetilide, Ibutilide, Sotalol
What are the effects of the class III antiarrhythmics (K channel blockers)?
• increases QT interval • slows repolarization
Name the class IV antiarrhythmics
• Ca channel blockers • Diltiazem & Verapamil
What are the effects of class IV antiarrhythmics (Ca Channel Blockers)?
• increased PR interval • slows AV nodal conduction
When do you use a class I-A antiarrhythmic?
for atrial & ventricular arrhythmias
What are adverse effects of Quinidine?
• nausea • vomiting • diarrhea • Cinchonism • Tinnitus (most common complaint)
What drug interacts with Quinidine?
warfarin
When should you avoid using Quinidine?
avoid using Quinidine for cardioversion because of GI effects
What is NAPA?
• NAPA is the active form of procainamide • Procainamide (inactive) is metabolized into its active form by the liver
What are adverse effects of Procainamide?
• decrease dose in renal and liver dysfunction because NAPA accumulates
What is the mechanism of action, adverse effects, and contraindications of Disopyramide (class I-A)?
• MOA: Na channel blocker, strong negative inotrope • AE: ACH side effects (Mad as a Hatter, Blind as a bat, Dry as a bone, Red as a Beet, Hot as a Pistol) • CI: Glaucoma
How do Class I-B antiarrhythmics work?
• slows conduction through ventricular tissue • decrease ICD (implantable cardioversion device) firing • weak antiarrhythmic
What is the mechanism of action and contraindications for Iidocaine?
• MOA: Na channel blocker • CI: 3rd degree heart block
What are adverse effects of Lidocaine?
• CNS symptoms • confusion • perioral numbness • seizures
When do you use Lidocaine?
• pulseless V-Tach/V-Fib • stable V-Tach
What is the mechanism of action, contraindications, and uses of Mexiletine?
• MOA: Na channel blocker • CI: 3rd degree heart block • Use: V-Tach maintenance & peripheral neuropathy
True/False: Class I-C antiarrhytmics increases ICD firing
The correct answer is: True
What the mechanism of action, adverse effects, contraindications and drug interactions of Propafenone?
• MOA: Na & Ca channel blocker, with some beta blockage • AE: metallic taste, dizziness • CI: CHF, hepatic & valvular disease • DI: Digoxin and Warfarin
What is the mechanism of action, adverse effects, contraindications and drug interactions of Flecainide?
• MOA: Na channel blocker, anticholinergic effects, and negative inotropic effects • AE: CHF exacerbations, dizziness • CI: CHF, valvular heart disease • DI: Digoxin
Which class I drugs can be monitored by blood levels?
Lidocaine, Procainamide (NAPA levels), and Mexiletine
What is the mechanism of action of Amiodarone?
Na+, K+, Ca++, Beta blocker effects
What are adverse effects of Amiodarone?
• blue-gray skin • hypothyroidism* • neurologic toxicities • pulmonary fibrosis* • torsades
What labs should be done prior to administering Amiodarone?
• pulmonary function tests and thyroid panel (TSH, T4, T3) • Amiodarone can cause life-long hypothyroidism
What are contraindications of Amiodarone?
• iodine hypersensitivity • hyperthyroidism • heart block (2° or 3°)
What are drug interactions of Amiodarone?
• digoxin • dilantin • warfarin • CYP 450 (2C9, 2D6, 3A4)
What adjustments need to be made on a patient on either warfarin or digoxin and given amiodarone?
• Amiodarone can increase INR (warfarin needs to be decreased by at least 25%) • monitor Dig level and possible decrease Digoxin level
When is Amiodarone used?
• Afib conversion • maintanence • Pulseless V-tach or V-fib • Stable V-tach
What is the dosing when giving Amiodarone to convert Afib?
• 150 mg IV bolus over 10 min. THEN • hang a drip: 450 mg/250 cc @ 13 cc/hr
What is the mechanism of action and contraindications of Sotalol?
• MOA: Beta 1, Beta 2, K+ channel blocker • CI: QTC greater than 440
What are adverse effects of Sotalol?
• bradycardia • CHF exacerbation • Torsades de Pointe (Sotalol increases QR interval) • wheezing
What are uses of Sotalol?
• Afib and V-tach maintenance • not effective for Afib conversion
What is the mechanism of action, adverse effects, and uses of Dofetilide?
• MOA: K+ channel blocker • AE: Torsades de Pointe if not adjusted renally • Uses: Afib conversion and maintenance
What are contraindications of Dofetiline?
• Baseline QTc > 440 • CrCl < 20 ml/min
What are drug interactions with Dofetilide?
• Cimetidine • Ketoconazole • Megestrol • Trimethoprim (Bactrim) • Verapamil
What is the dosing of Dofetilide?
• 20 < CrCl < 30, 125 mcg PO Q12 hrs • 30 < CrCl < 60, 250 mcg PO Q12 hrs • CrCl > 60, 500 mcg PO Q12hrs
What information and labs are needed before administering Dolfetilide?
height, weight, serum creatinine, and baseline EKG
True/False: Dofetilide is available in PO and IV formulations
Dofetilide is only PO The correct answer is: False
What is the mechanism of action, adverse effects, contraindications, drug interactions, and uses of Ibutilide?
• MOA: Strong K+ channel blocker with Na+ and beta-blocking effects • AE: Torsades de Pointe (requires EKG monitoring) • CI: Baseline QTc greater than 440 • DI: any drug that prolongs QT interval • Uses: Afib conversion
What antiarrhythmics can be used if Afib duration is less than 48 hours?
• Dofetilide • Flecainide • Ibutilide • Propafenone
Which antiarrhythmic would be used with left ventricular dysfunction (CHF)?
Amiodarone and Dofetilide
What antiarrhythmics can be used with normal left ventricular function with CAD?
• Amiodarone • Dofetilide • Sotalol
What antiarrhythmics should be used with a normal left ventricular function without CAD?
• Disopyramide • Flecainide • Propafenone • Sotalol
What anticoagulation therapy is recommended for a patient with low risk Afib?
• Aspirin 325 mg daily • low risk patient have no stroke risk factors
What anticoagulation therapy is recommended for a moderate risk patient with AF
What anticoagulation therapy is recommended for a patient with high risk AFib?
• Warfarin (INR 2-3) • Aspirin 325 mg dailiy (if warfarin is contraindicated or refused) • risk factors: > 75 y/o, HTN, CHF, prosthetic heart valve, TIA, thromboembolism
What drugs are used to treat PVCs?
• beta blockers • avoid class I and II
What drugs are used to treat asymptomatic NSVT w/o structural disease?
no treatment is needed
What drugs are used to symptomatic NSVT w/o structural disease?
beta blockers (drug of choice)
What is the treatment of NSVT with structural disease?
• if EF > 40 » no treatment • if EF < 40 » evaluate for ICD
What is the treatment for sustained VT (with QTc not prolonged)?
• if EF > 40 » procainamide, lidocaine, or amiodarone • if EF < 40 » amiodarone or lidocaine
What is the treatment for polymorphic ventricular tachycardia (ie Torsades de Pointe)?
IV Magnesium, Isoproterenol, Transvenous Pacemaker