Atrial arrhythmias Flashcards
1
Q
three general classifications for AF
A
paroxysmal, persistent, and permanent
2
Q
paroxysmal AF
A
- AF terminates spontaneously within 7 days of onset
- most lasts less than 24 hours
- may recur with variable frequency
3
Q
persistent AF
A
- continuous AF that is sustained for > 7 days and does not terminate on its own
- electrical or pharmacological cardioversion does not change the classification
4
Q
permanent AF
A
does not terminate with attempts at pharmacologic or electrical cardioversion OR joint decision between patient and clinician to cease further attempts to restore/maintain sinus rhythm
5
Q
acute AF
A
onset within last 48 hours
6
Q
recurrent AF
A
when a patient has had 2 or more episodes (either paroxysmal or persistent can be recurrent)
7
Q
Lone AF
A
applies to younger individuals ( < 60 years of age) without evidence of underlying cardiopulmonary disease
8
Q
average rate of stroke in AF patients with no coagulation therapy
A
5% per year
9
Q
t/f AF is viewed as a cardio disease
A
false, but it causes poor clinical outcomes from other things (like strokes)
10
Q
_____% of all strokes are due to AF
A
15 percent
11
Q
risk of stroke is ______ greater than people without AF
A
five times
12
Q
cardiovascular conditions associated with AF
A
- heart failure
- valvular heart disease
- coronary artery disease
- hypertension
- diabetes
13
Q
secondary AF or acute causes of AF
A
- MI or cardiac surgery
- hyperthyroidism
- PE
- pericarditis
- alcohol intake
14
Q
t/f AF more common in Caucasians than AA
A
true
15
Q
definition of atrial fibrillation
A
supraventricular tachyarrhythmia characterized by uncoordinated atrial activation caused by re-entry arrhythmias with consequent deterioration of atrial mechanical function
16
Q
AF is characterized by what atrial rate
A
400-600 bpm
17
Q
in AF the atria usually displays
A
structural abnormalities beyond those caused by underlying diseases
18
Q
mechanism of a fib
A
multiple atrial re-entrant loops
19
Q
loss of atrial kick leads to
A
decreased CO and irregular ventricular response thus the rhythm becomes “irregularly irregular”
20
Q
symptoms of PSVT
A
- intermittent episodes of rapid HR/palpitations
- abruptly start and stop without provocation
- syncope, chest or neck pressure
21
Q
treating severe symptoms of PSVT
A
extremely rapid HR ( > 200 bpm)
- treatment of choice is DCC/shock
22
Q
treating mild-moderate symptoms
A
- patients usually don’t need DCC
- use non drug measures
23
Q
common symptoms in a fib patients
A
- palpitations
- rapid HR
- worsening HF
- fatigue
- chest pain
- syncope
24
Q
a fib EKG
A
- irregularly irregular supraventricular rhythm
- no P waves
- ventricular response usually 120 to 180 bpm
25
a flutter EKG
- regular supraventricular rhythm
- characteristic saw tooth flutter waves
- ventricular rate depends on how many atrial depolarizations are conducted
26
non drug measures to treat PSVT
- unilateral carotid massage
- Valsalva maneuvers
- induced retching
- ice water facial immersion
27
adenosine moa
prolong conduction time in slow antegrade pathway of the reentrant loop to terminate PSVT
28
verapamil and diltiazem moa
prolong conduction time in slow antegrade pathway of the reentrant loop to terminate PSVT
29
drug interactions for non dhp ccbs
3a4 inhibitors - careful with statins, hiv meds, and benzos
30
non dhp ccb clinical pearls
- 2nd line agent: SLOW IV push
| - can switch to po therapy if needed long term
31
first line treatment for automatic atrial tachycardia
verapamil and diltiazem
32
second line treatment for automatic atrial tachycardia
IV magnesium (high doses)
33
hemodynamic instability
AF with severe hypotension, pulmonary edema, or in setting of acute MI
34
if pt has normal LV function what drug do you put them on initially
1. IV b-blockers
| 2. IV diltiazem or IV verapamil
35
if pt has LV dysfunction what drug do you put them on initially
1. IV digoxin
| 2. IV amiodarone
36
affirm trial
- largest trial for rate v. rhythm control
- no statistical difference
- tendency towards increased mortality in rhythm control group
37
rate control is for
patients who are NOT symptomatic
38
rate control IV used in
acute setting, po can be used in non acute
39
drugs used in rate control
- metoprolol
- atenolol
- diltiazem
- verapamil
- digoxin
40
major side effects of metoprolol
hypotension, bradycardia, heart block, bronchospasm, heart failure
41
clinical use of metoprolol
1st line for adrenergic state; avoid in asthma/COPD
42
major side effects of atenolol
hypotension, bradycardia, heart block, bronchospasm, heart failure
43
clinical use of atenolol
1st line for adrenergic state; avoid in asthma/COPD
44
major side effects of diltiazem
hypotension, bradycardia, heart failure, heart block, constipation
45
clinical use of diltiazem
use in caution in HF; preferred in asthma/COPD
46
major side effects of verapamil
hypotension, bradycardia, heart failure, heart block, constipation
47
clinical use of verapamil
use in caution in HF; preferred in asthma/COPD
48
major side effects of digoxin
digitalis toxicity, heart block, bradycardia, use with caution in patients with renal failure
49
clinical use of digoxin
preferred in HFrEF patients for acute VR control; long term may switch to BB for HFrEF therapy
50
adequate maintenance rate control
resting heart rate of < 80 bpm and < 100 bpm during exercise
51
advantages to cardioversion
- relief of symptoms (palpitations fatigue, dyspnea)
- prevention of thromboembolism
- prevention of tachycardia induced myocardial remodeling and cardiomyopathy
52
disadvantages to cardioversion
- antiarrhythmic agents generally have more side effects and are not as safe as agents used to control heart rate
- increases risk of thromboembolism
53
AF duration > 48 hours and anticoagulants
- increased risk of formation
- anticoagulation > 3 weeks prior to conversion
- continue anticoags for 4 weeks after cardioversion (possible lifelong treatment if stroke risk factors)
54
AF duration < 48 hours and anticoagulants
anticoags prior to cardioversion not needed
55
electrical cardioversion
- most effective method
| - disadvantage is that it requires anesthesia and sedation
56
pharmacological cardioversion
less effective than DCC; tends to be more effective if AF onset < 7 days prior to cardioversion
57
drugs for cardioversion
- flecainide
- propafenone
- dofetilide
- ibutilide
- amiodarone
58
flecainide clinical pearls
pt needs to be on av node blocker (BB or NonDHP ccb) to start; contraindicated in patients w CAD and HF
59
propafenone clinical pearls
pt needs to be on av node blocker (BB or NonDHP ccb) to start; contraindicated in patients w CAD and HF
60
dofetilide ae
qt prolongation; torsades de pointes
| adjust doses based on renal function
61
dofetilide contraindicated with
- cimetidine
- ketoconazole
- prochlorperazine
- trimethoprim
- megesterol
- verapamil
- diltiazem
62
ibutilide ae
qt prolongation, torsades de pointes
63
ibutilide clinical pearls
contraindicated in pts w HF
64
amiodarone loading therapy ae
hypotension, bradycardia, QT prolongation, GI upset
65
rhythm maintenance drugs
- amiodarone
- dofetilide
- flecainide
- propafenone
- sotalol
- dronedarone
66
sotalol ae
torsades de pointes, heart failure, exacerbation of bronchospastic disease, bradycardia
67
dronedarone ae
torsades de pointes, heart failure, GI upset, liver failure, avoid 3A4 inhibitors
68
highest risk factors for stroke in a fib patients
- mitral valve stenosis
- prosthetic heart valve
- prior stroke or tia
69
medium risk factors for stroke in a fib pts
- age >75
- hypertension
- diabetes
- CHF/LV dysfunction
70
vascular disease =
prior MI, PAD, or aortic plaque
71
chadsvasc score of 0 in men/ 1 in women
no anti-thrombotic therapy
72
chadsvasc score of 1 in men/ 2 in women
oral anticoag can be considered. NOACs preferred
73
chadsvasc score of 2 or more in men / 3 or more in women
treatment with NOAC preferred over warfarin
74
pts with valvular a fib
warfarin is only recommendation
75
dabigatran moa
direct oral thrombin inhibitor
76
dabigatran dosing
normal: 150 bid
CrCl < 30 = 75 bid
CrCl < 15 = do not use
77
drug interactions with dabigatran
- avoid use with rifampin and carbamazepine
| - use 75 mg in pts taking verapamil, ketoconazole, amiodarone, or dronedarone
78
missed doses of dabigatran
if > 6 hours to next dose, take missed dose; if not, skip dose
79
dabigatran clinical pearls
- very sensitive to moisture
| - gastritis common
80
RE-LY trial
- dabigatran 150 bid non inferior to unblinded warfarin, less number of strokes with more major bleeding
- dabigatran 110 bid non inferior to warfarin with same number of strokes and less major bleeding
81
rivaroxaban moa
factor 10a inhibitor
82
rivaroxaban dosing
normal: 20 mg with dinner
CrCl < 15-50: 15 mg daily
do not use if crcl lower than 15
83
drug interactions with xarelto
- avoid in cyp3a4 inducers; phenytoin, carbamazepine, and rifampin
- cyp3a4 inhibitors: ketoconazole, itraconazole, ritanovir, clarithromycin
84
Xarelto missed doses
take missed dose ASAP on same day, resume next day on normal schedule
85
Xarelto clinical pearls
any dose greater or equal to 15 = take with food
| not recommended in lactose intolerant pts
86
ROCKET AF trial
rivaroxaban non inferior to warfarin in stroke prevention with no significant difference in clinically major bleeding. ICH and fatal bleeding lower in xarelto
87
apixaban moa
factor 10a inhibitor
88
apixaban dosing
```
normal : 5 mg bid
if:
- < 60 kg
- age > 80
- SCr > 1.5
dosing is 2.5 mg bid
```
89
apixaban drug interactions
- use 2.5 mg bid when taking clarithromycin, ketoconazole, itraconazole, or ritanovir
- avoid use w rifampin, carbamazepine, phenytoin, st. johns wort
90
missed doses of apixaban
take asap and resume bid dosing, do not double up
91
clinical pearls of eliquis
grapefruit juice may increase effects
92
ARISTOTLE trial
apixaban non inferior and superior to warfarin for prevention of stroke with lower major clinical bleeding
93
edoxaban moa
10a inhibitor
94
edoxaban dosing
crcl >95 do not use
normal: 60 mg daily
crcl 15-50: 30 mg daily
crcl < 15 do not use
95
edoxaban drug interactions
- rifampin, carbamazepine
| - 30 mg daily if pt taking verapamil, dronedarone, or quinidine
96
edoxaban missed dose
take asap; resume next day schedule
97
edoxaban clinical pearls
crcl > 95 with AF bad bc of increased risk of stroke as compared to warfarin
