Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
78 Cards in this Set
- Front
- Back
|
What kind of tachycardia is AF?
|
supraventricular
|
|
|
Does AF occur more in men or women and what age group?
|
men and elderly
|
|
|
What is acute AF?
|
onset within 48 hours
|
|
|
What is paroxysmal AF?
|
terminates spontaneously in <7 days
|
|
|
What is recurrent AF?
|
2 or more episodes
|
|
|
What is persistent AF?
|
duration >7 days and doesn't terminate spontaneously
|
|
|
What is permanent AF?
|
does not terminate with pharmacologic and electrical cardioversion attempts
|
|
|
What are the characteristics of AF?
|
atrial rate 400-600bpm
disorganized atrial activation |
|
|
Why is ventricular response considerably slower than atrial rate?
|
AV junction will not conduct most supraventricular impulses
|
|
|
What are characteristics of atrial flutter?
|
atrial rate 300bpm
regular atrial activation |
|
|
What is type I flutter?
|
common classic form with atrial rate 300bpm and typical "sawtooth" pattern of atrial activation
|
|
|
What is type II flutter?
|
faster than type I, hyprid between flutter and AF
|
|
|
What is the predominant mechanism of AF and flutter?
|
reentry
|
|
|
What causes AF?
|
multiple reentrant loops
|
|
|
What causes atrial flutter?
|
single dominant reentrant substrate
|
|
|
Do AF pts typically have syncope?
|
no
|
|
|
What is a severe complication that can result for AF?
|
stroke
|
|
|
How much more of a risk for stroke is a person with AF and rheumatic heart disease compared to pt at sinus rhythm?
|
17x
|
|
|
What is a risk of restoring rhythm in AF pts?
|
thromboembolism
|
|
|
When is DCC first line to restore rhythm?
|
if pt is not hemodynapically stable (severy hypotension, angina, pulmonary edema)
|
|
|
What energy level is usually required in DCC for AF?
|
200 joules
|
|
|
What energy level is usually required in DCC for atrial flutter?
|
50 joules
|
|
|
If pt is hemodynamically stable, what should tx focus on?
|
restoring rate
|
|
|
What drugs are used for resoring rate?
|
drugs that slow conduction and increase refractoriness in the AV node
BB (II) nondihydropyridine (IV) digoxin |
|
|
What rate controlling drug is not used if pt has normal LV systolic function (LVEF >40%)?
|
digoxin
|
|
|
Why is digoxin not used if normal LV systolic function (LVEF>40%)?
|
slow onset and inability to control heart rate during exercise
full control is not achieved for 24-48hrs not good if increased sympathetic tone (surgery, thyrotoxicosis) because slows AV nodal conduction |
|
|
Why are BB and nondihydropyridine CCBs preffered?
|
quick onset and can control rate at rest and exercise
|
|
|
What drug is effective at controlling ventricular rate if increased sympathetic tone?
|
BB
|
|
|
What IV BB are used for AF?
|
propranolol, metoprolol, esmolol
|
|
|
How are the BB given?
|
propranolol and metoprolol are given in intermittent IV boluses
esmolol is given as a loading dose then continuous infusion because t1/2 5-10min |
|
|
How are nondihydropyridines CCB given IV?
|
bolus then continuous infusion
|
|
|
What is first line if pt is in HF and LVEF <40%?
|
diltiazem or amiodarone
|
|
|
Why are CCB avoided in HF?
|
potent negative inotropic effects
|
|
|
What is risk of using amiodarone for rate control?
|
may be rhythm control also and cause thromboembolic event
|
|
|
What should be present if slow ventricular response and going to do DCC?
|
pacemaker
|
|
|
What drugs should not be used if slow ventricular response?
|
BB, CCB, or digoxin
|
|
|
When should rhythm tx be considered?
|
after decrease in ventricular rate
|
|
|
What were the results of the AFFIRM trial?
|
mortality was not different between rate and rhythm control. Rate control is a viable alternative to rhythm control.
|
|
|
If on BB or CCB chronically for rate control, what can be added if not getting effect?
|
digoxin
|
|
|
If bb, CCB, and digoxin do not control rate at rest and exercise, what is an alternative tx?
|
amiodarone
|
|
|
What should be used to treat chronic pts if LVEF <40%?
|
BB or digoxin, BB over digoxin because survival benefits in pt with LV systolic dysfunction is greater
|
|
|
If pt is have decompensated HF, what is first line for rate control?
|
digoxin
|
|
|
What is it called when chronic tachycardia results in progressive decline in LV function?
|
tachycardia-induced cardiomyopathy
|
|
|
What is tx for tachycardia induced cardiomyopathy?
|
transvenous catheter delivering radiofrequency current
|
|
|
When does pt become at increased risk of thrombotic event when in AF?
|
AF longer than 48 hours
|
|
|
When should pt receive antithrombotic before cardioversion?
|
if AF longer than 48hrs or unsure how long
|
|
|
How long, what drug, what goal for antithrombotic tx?
|
warfarin for atleast 3 weeks before cardioversion, INR goal 2-3, continue 4 weeks after cardioversion
|
|
|
After cardioversion, how long before rhythm returns to normal?
|
3-4 weeks
|
|
|
If thrombus present, can you do cardioversion?
|
not until thrombus is gone, anticoagulate indefinately
|
|
|
How do you prepare for cardioversion if AF <48 hrs?
|
don't need anticoagulant for 3 weeks because there wasn't time for thrombi to form.
Pt should receive unfractionated heparin or LMW heparin prior to cardioversion |
|
|
What are disadvantages of pharmacologic cardioversion?
|
risk of significant SE (TdP), DDI, less effective than DCC
|
|
|
What are the advantages of DCC (direct current cardioversion)?
|
quick and more often successful
|
|
|
What are disadvantages of DCC (direct current cardioversion)?
|
sedation, serious complication such as sinus arrest or ventricular arrhythmias
|
|
|
When is pharmacologic cardioversion most effective?
|
if initiated within 7 days of AF
|
|
|
What pharmacologic agents are used most often?
|
type III pure Ik blockers (ibutilide, dofetilide), type Ic, and amiodarone
|
|
|
What is "pill-in-the-pocket" method?
|
outpatient single loading dose of flecainide or propafenone
only use if this worked inpatient before |
|
|
What is tx for cardioversion of pt has AF for longer than 7 days?
|
dofetilide, amiodarone, and ibutilide (type III)
|
|
|
What can be used for cardioversion if no heart disease present?
|
loading dose of propafenone or flecainide (type Ic)
ibutilide can be used also but inpatient only because IV |
|
|
If underlying heart disease what agents should be used?
|
amiodarone or dofetilide
the others increase risk of proarrhythmia amiodarone can be done outpatient dofetilide is inpatient only because low proarrhythmic potential |
|
|
What antiarrhythmics can actually increast ventricular response?
|
Ia and Ic
|
|
|
What are the risk factors that require long term anticoagulation with warfarin?
|
rheumatic mitral valve disease
previous ischemic stroke TIA any other embolic event >75 years old moderate or severe LV systolic dysfunction congestive HF HTN prosthetic heart valve |
|
|
Who is at intermediate risk? What should they be treated with?
|
65-75 years old with no risk factors
warfarin or aspirin 325mg/day |
|
|
Who is at low risk? What tx?
|
<65 years old
aspirin 325mg/day |
|
|
When are type Ia agents considered?
|
last line in pt without HD, with HTN, without LV dysfunction, without CAD
|
|
|
What pts should avoid Ic?
|
pt with structural heart disease because proarrhythmic
|
|
|
What is the most effective antiarrhythmic?
|
amiodarone
|
|
|
Can sotolol be used for rhythm control?
|
not effective for conversion but effective for maintaining sinus rhythm
|
|
|
Can dofetilide be used for rhythm control?
|
yes, also shown efficacy if pt with LV dysfunction
|
|
|
Which antiarrhythmic drugs have the most long-term safety profile?
|
flecainide, propafenone, sotalol
if no structural heart disease |
|
|
What can alternative be if pt fails or does not tolerate one of the above?
|
amiodarone or dofetilide
|
|
|
Which drugs should be avoided in heart disease?
|
flecainide, propafenone, proarrhythmic
|
|
|
What is used if LV dysfunction present?
|
amiodarone
dofetilide if alternative needed |
|
|
What is used if pt has CAD?
|
sotalol
amiodarone or dofetilide for alternative |
|
|
What is highly effective nondrug for pure type I atrial flutter?
|
ablation with radiofrequency current (can be considered 1st line)
|
|
|
What surgery can be done for AF?
|
maze operation, highly complex and invasive
only use for highly drug refractory pts |
|
|
What nondrug is recommended for AF?
|
catheter ablation
|
|
|
When is catheter ablation considered?
|
pt with symptomatic episodes of recurrent AF who fail or do not tolerate at least one antiarrhythmic drug
|
|
|
what is first line if pt is HTN with LVH?
|
amiodarone
|
