Term
What is the chief complaint when a patient comes in for an arrhythmia? |
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Definition
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Term
T/F Bradycardia presentation is usually different from other arrhythmias. |
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Definition
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Term
How do bradycardias present? |
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Definition
chronic fatigue dyspnea on exertion syncope or near syncope |
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Term
How might you discover an arrhythmia in an asymptomatic patient? |
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Definition
checking vitals - pulses auscultation of the heart routine EKG |
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Term
What lab tests would you run on a patient with an arrhythmia? |
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Definition
chem panel - electrolytes and glucose CBC - anemia TSH EKG |
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Term
When should you absolutely not give amiodarone? |
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Definition
pregnancy and during lactation |
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Term
What anti-arrhythmic drugs should not be given during lactation? |
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Definition
amiodarone and acebutolol |
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Term
T/F During pregnancy there is an increase in arrhythmias. |
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Definition
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Term
T/F Pseudophedrine or other sympathomimetic drugs may cause an arrhythmia. |
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Definition
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Term
What are the potential cardiac causes of PACs? Other causes? |
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Definition
cardiac: mitral stenosis, CAD, hypertrophic cardiomyopathy
other: caffeine, theophylline, tobacco, alcohol, COPD, chronic renal |
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Term
What EKG changes are there to indicate PACs (premature atrial contraction)? |
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Definition
short or prolonged PR interval inverted or biphasic p waves aberrant or absent QRS |
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Term
How do you treat asymptomatic patients with PACs? |
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Definition
education, reassurance, possible dietary/med changes if causative agent |
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Term
How do you treat symptomatic patients with PACs? |
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Definition
beta blockers - variable results refer to cardiologist |
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Term
What medications should not be used to treat symptomatic patients with PACs? Why? |
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Definition
IA, IC, or III anti-arrhythmic agents (quinidine, procainamide, flecainide or those that inhibit ventricular repolarization or prolong refractoriness)
high risk for proarrhythmia and QT prolongation |
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Term
How are anti-arrhythmic drugs classified? |
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Definition
Vaughn-Williams Classification
classified by effect on ventricular contraction velocity, repolarization/refractoriness, and automaticity |
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Term
What are Class I anti-arrhythmics? |
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Definition
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Term
What are class II anti-arrhythmic agents? |
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Definition
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Term
What are class III anti-arrythmic agents? |
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Definition
drugs that inhibit ventricular repolarization or prolong refractoriness |
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Term
What are class IV anti-arrhythmic agents? |
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Definition
non-dihydropyridine CCBs: verapamil and diltiazem |
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Term
T/F Some drugs can have multiple anti-arrhythmic classifications based on it's effects. |
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Definition
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Term
What are the classifications of Ia, Ib, and Ic? |
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Definition
Ia - intermediate, intermediate potency Ib - fast on/off, lowest potency Ic - slow on/off, highest potency |
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Term
What do class I anti-arrhythmic agents do? |
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Definition
1. lengthen the refractory period 2. decrease excitability 3. decrease conduction 4. block K+ channels - mild 5. lengthen the action potential duration - wider QRS |
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Term
T/F The effect of class I anti-arrhythmic drugs is rate dependent. |
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Definition
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Term
When is slowed conduction apparent for class Ib drugs? |
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Definition
only apparent at fast rates |
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Term
When is slowed conduction apparent for Ic drugs? |
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Definition
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Term
T/F Normal tissues are affected by class Ib drugs. Ic drugs? |
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Definition
False True - Ic drugs affect all tissue |
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Term
T/F The effect of class I anti-arrhythmic drugs is pH dependent. |
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Definition
True - original compounds are bases and become active by adding an H+
acidosis will increase effects alkalosis will decrease effects |
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Term
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Definition
quinidine and procainamide |
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Term
What is quinidine syndrome? |
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Definition
recurrent light-headed-ness, fainting, and drug-induced Torsade de pointes caused by quinidine |
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Term
What are some problems associated with procainamide? |
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Definition
arthralgia similar to lupus in 33% icreased ANA titer pleuritis pericarditis |
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Term
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Definition
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Term
What are 2 potential problems with using lidocaine? |
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Definition
must be injected properly or it can cause cardiac effects
can cause hypotension by depressing myocardial contractility |
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Term
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Definition
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Term
Which drug would you use the lowest dose on and has the longest lasting effect - Ia, Ib, or Ic? |
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Definition
Ic because it is the highest potency |
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Term
What EKG changes typify PVCs? |
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Definition
wide, bizarre QRS QRS > .12 sec inverted T wave compensatory pause following QRS |
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Term
What % of middle aged people have PVCs on a 2 minute EKG? |
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Definition
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Term
T/F Post MI, more than 10 PVCs per hour is associated with a worse prognosis. |
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Definition
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Term
What % of HF or cardiomyopathy patients have PVCs? Are they of prognostic value? |
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Definition
70-95%
No prognostic value |
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Term
T/F Patients with LVH have an increased incidence of PVCs and it correlates to a higher risk of sudden death. |
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Definition
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Term
How do you treat a patient with PVCs who has no heart disease? |
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Definition
You don't!
anti-arrhythmic therapy increases the risk of death |
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Term
How do you treat the patient with PVCs and structural heart disease (CAD, cardiomyopathy, CHF)? |
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Definition
radiofrequency ablation and referral for Class I anti-arrhythmic drugs and perhaps amiodarone |
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Term
How do you treat the symptomatic patients with PVCs in the outpatient setting? |
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Definition
First line - class II - beta blockers - sotalol - class II and III
amiodarone may be used if Beta blockers are counterindicated |
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Term
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Definition
class II and class III anti-arrhythmic drug
Do not use in asymptomatic patients due to proarrhythmia affects
treat with O2 to avoid proarrhythmic affects of beta blockers |
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Term
Who should not be treated with beta blockers? |
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Definition
asymptomatic patients with PVCs - possible proarrhythmia effects |
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Term
Name 4 possible causes of bradycardia. |
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Definition
1. Sick sinus syndrome 2. exaggerated vagal activity 3. acute MI 4. obstructive sleep apnea |
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Term
How do you treat the asymptomatic patient with bradycardia? |
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Definition
You don't!
increase O2, have pt lie supine with raised legs, increase fluids if no JVP distension |
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Term
How do you treat the symptomatic patient with bradycardia? |
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Definition
may require pacing adrenaline isoprenaline |
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Term
What is the heart rate in PSVT? |
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Definition
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Term
What is the heart rate in atrial flutter? |
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Definition
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Term
What is the heart rate in atrial fibrillation? |
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Definition
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Term
Describe the EKG of PSVT. |
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Definition
narrow complex tachycardia with a regular rate |
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Term
What % of cases of PSVT are AV nodal re-entrant? AV re-entrant? atrial tachycardia or sinoatrial tachycardia? |
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Definition
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Term
What disorder is AV re-entrant tachycardia associated with? |
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Definition
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Term
T/F PSVT is benign and self-limited. |
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Definition
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Term
What are some types of non-pharmacologic treatment fro PSVT? |
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Definition
vagal maneuvers avoid: caffeine, alcohol, tobacco, stress, pseudophedrine ice-cold wet cloth to the face stimulate gag reflex bend over and touch floor exhale followed by deep inspiration with mouth closed and nose pinched |
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Term
What is the most common symptomatic pediatric arrhythmia? |
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Definition
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Term
T/F PSVT that is sustained with instability requires immediate cardioversion. |
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Definition
True
instability may be: angina, SOB, decreased level of consciousness, hyptension, or CHF |
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Term
When is adenosine cardioversion counterindicated? |
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Definition
wide complex tachycardia and in WPW (delta waves) |
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Term
What drug is used to cardiovert narrow complex PSVT? |
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Definition
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Term
After cardioversion with adenosine, what is used for maintenance? |
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Definition
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Term
What is the mechanism of action of adenosine? |
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Definition
enhanced K conductance suppression of calcium dependent action potentials
This inhibits AV nodal conduction and increases the AV nodal refractory period |
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Term
What are the signs and symptoms of adenosine toxicity? |
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Definition
flushing - 20% SOB or chest burning - 10% headache hypotension nausea |
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Term
How do you treat PSVT in outpatient? |
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Definition
cautious use of beta-blocker verapamil |
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Term
How do you treat PSVT in ED? |
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Definition
emolol selective radiofrequency ablation cardioversion - start at 50J |
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Term
Describe atrial fibrillation. |
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Definition
Irregularly irregular wavy baseline with no P waves 350-600 bpm Ventricular response 120-180 bpm |
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Term
What classifies acute atrial fibrillation? |
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Definition
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Term
What classifies paroxysmal atrial fibrillation? |
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Definition
terminates spontaneously in 7 days |
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Term
What classifies persistent atrial fibrillation? |
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Definition
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Term
T/F Permanent atrial fibrillation is not pharmacologically or electrically convertible. |
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Definition
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Term
T/F In atrial fibrillation there are multiple re-entrant pathways. |
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Definition
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Term
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Definition
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Term
What is the drug of choice to treat atrial fibrillation and atrial flutter? Name 2 other drugs that may be used. |
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Definition
Digoxin
Beta blockers and CCBs - used to control the rate; may not be beneficial; unmask heart failure |
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Term
T/F Anticoagulate with atrial fibrillation and atrial flutter. |
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Definition
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Term
What do you use to anticoagulate a patient with atrial fib or atrial flutter? |
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Definition
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Term
Which clotting factors are destroyed by Protein C? |
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Definition
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Term
Which factors are inactivated by heparin? |
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Definition
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Term
How does heparin inactivate clotting factors? |
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Definition
by activating anti-clotting factors such as antithrombin III which inactivates 7a, 9a, 10a, and 2a |
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Term
Which clotting factors' synthesis is inhibited by warfarin? |
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Definition
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Term
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Definition
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Term
Where does Warfarin sodium act? |
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Definition
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Term
How long do the effects of warfarin take to show up? Why does it take so long? |
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Definition
1-3 days
1. some clotting factors have long half lives, so it takes time for their synthesis inhibition to be seen 2. It takes time to get to the peak drug concentration |
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Term
What is the bioavailability of Warfarin? |
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Definition
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Term
What is the half-life of coumadin? |
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Definition
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Term
What is a warfarin diet? Why might it be followed? |
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Definition
avoiding green leafy veggies because they are a source of vitamin K
Vitamin K is used to make clotting factors and therefore reduces the efficacy of the warfarin |
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Term
T/F Patients on coumadin may need higher dosing in the winter. |
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Definition
False - they may need higher dosing in the summer |
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Term
What meds should be avoided while on coumadin therapy? |
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Definition
NSAIDs and aspirin (reduce to 81 mg daily at least) |
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Term
What pregnancy category is warfarin? |
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Definition
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Term
How do you dose coumadin? |
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Definition
Increase dose at 1 week intervals based on INR
INR of 2-3 for anticoagulation INR of 2.5-3.5 for mechanical heart valve patients INR of 1.5-2.0 to prevent VTE after first six months of therapy |
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Term
T/F Drug interactions with warfarin are numerous |
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Definition
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Term
What drugs increase the INR of a patient on coumadin? |
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Definition
amiodarone antibiotics antifungals omeprazole cimetidine |
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Term
How do you treat overcoagulation with warfarin? |
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Definition
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Term
Why should you limit OTC remedies with a patient on coumadin therapy? |
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Definition
herbal interactions also exist |
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Term
What is the success rate for direct-current cardioversion in a fib and atrial flutter? |
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Definition
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Term
What drug is given 3-4 weeks before attempting cardioversion of a fib and atrial flutter? |
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Definition
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Term
What test should be done before conversion? |
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Definition
transesophageal ECHO to find atrial thrombi that would require anticoagulation before conversion |
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Term
What 2 drugs do you use to maintain rhythm after cardioversion? |
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Definition
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Term
Which drug is used to pharmacologically convert a fib or a flutter? What is the success rate? |
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Definition
high dose amiodarone
86% if a fib has existed less than 2 years |
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Term
What is the action of amiodarone? |
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Definition
1. slows the sinus rate 2. slows AV conduction - prolongs QT interval and QRS complex 3. increases refractory periods |
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Term
T/F Amiodarone is prorhythmic. |
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Definition
True - it is unlikely that an arrhythmia will develop or worsen while on this med. |
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Term
What is the mechanism of action of amiodarone? |
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Definition
1. Fast Na+ channel blocker 2. K+ channel blocker 3. noncompetative alpha and beta blocker 4. weak Ca2+ channel blocker |
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Term
How is amiodarone classified as an anti-arrhthmic? |
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Definition
could be classified as Class I, II, III, or IV |
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Term
What are the 2 effects of amiodarone? |
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Definition
antianginal and peripheral vascular dilation |
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Term
T/F The number and severity of toxic effects increases with the dosage of amiodarone. |
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Definition
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Term
Name 3 cardiac side effects of amiodarone. |
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Definition
bradycardia heart block heart failure |
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Term
What % of patients on amiodarone develop pulmonary fibrosis? |
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Definition
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Term
What are some of the extra-cardiac side effects of amiodarone? |
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Definition
pulmonary fibrosis, skin deposits - photodermatits or blue discoloration, CNS paresthesia, tremor, ataxia, headache, thyroid dysfunction - hyper or hypo, and liver necrosis |
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Term
What % of patients on amiodarone develop photodermatitis? Smurf discoloration? thyroid dysfunction? |
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Definition
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Term
When do the effects of interaction between amiodarone and concomittant therapy peak? |
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Definition
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Term
How often should liver and thyroid function tests be done on amiodarone pts? |
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Definition
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Term
At which dose of amiodarone is there a low incidence of lung or thyroid effects? |
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Definition
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Term
What is the half life of amiodarone? |
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Definition
highly variable and unusually long - averaging about 58 days |
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Term
When might Torsade de pointes be seen? |
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Definition
When a pacemaker is past the end of its life and needs to be replaced |
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Term
What typifies a ventricular tachycardia? |
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Definition
wide QRS compex - VT until proven otherwise
other: evidence of AV dissociation, independent p waves, capture of fusion beats, beat to beat variability in QRS morphology, QRS complexes > .14 secs |
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Term
T/F History of ischemic heart disease makes VT more likely. |
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Definition
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Term
How high is the mortality rate for VT after 2 years? |
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Definition
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Term
What is the best treatment for VT? |
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Definition
auto cardioverter-defibrillator implantation |
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Term
How do you treat hemodynamically unstable VT patients? |
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Definition
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Term
How do you treat stable VT patients? |
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Definition
amiodarone until implant can be put in |
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Term
T/F Athletes tend to have low HRs. |
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Definition
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Term
How long can an asymptomatic sinus pause be and still be benign in an athlete? |
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Definition
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Term
What is responsible for some cardiac related deaths in athletes? |
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Definition
idiopathic hypertrophic cardiomyopathy |
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Term
How do you diagnose idiopathic hypertrophic cardiomyopathy? what is the treatment? |
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Definition
aortic murmur that increases with Valsalva's maneuver
stop playing sport |
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Term
Supraventricular tachycardias in children are usually associated with what disorder? How do you treat? |
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Definition
WPW
adenosine or radiofrequency ablation |
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Term
What drug might you consider to control the heart rate in children (when there are extra beats)? |
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Definition
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