E.4 Atrial Fibrillation Flashcards
____ is the most common arrythmia.
Atrial Fibrillation
Atrial Fibrillation is most common in those above _____
80 years old.
What are the primary two causes of atrial fibrillation.
1) Scarring or Fibrotic Tissue
2) Changes to cardiac action potential (electrolyte abnormalities, drugs)
Genetic Diseases are also a factor
Atrial fibrillation is often described as disorganized and irregular atrial electrical activity. This presents as a “quivering” on an ECG. In this case there is no distinguishable atrial depolarization/contraction corresponding to ____ waves.
P-waves.
Atrial fibrillation occurs when atrial tissue is ____
modified due to abnormalities in structure or function.
Atrial rate in Afib
600-800 bpm
Ventricular Rate in Afib
100-180 bpm.
Afib is triggered by rapidly firing ____ in the atria.
Ectopic Beats
Atrial fibrillation which terminates within 7 days of onset.
Paroxysmal
Atrial fibrillation which lasts longer than 7 days.
Persistent
Atrial fibrillation lasting longer than 12 months.
Longstanding, persistent.
Atrial fibrillation where the patient and clinician have decided that there will be no more effort to restore or maintain sinus rhythm.
Permanent
List some of the clinical manifestations of Afib.
- Fatigue
- Palpitations
- Shortness of Breath
- Hypotension
- Dizziness, Light-headedness
- Syncope
T or F: Many Afib patients are asymptomatic.
True.
What is AFib with Rapid Ventricular Rate (RVR)
An acute presentation of Afib where the patient has a higher HR due to more conduction through the AV node. This leads to ventricular tachycardia.
Afib increases the risk of stroke by ____
5 Fold
Afib increases the risk of heart failure by ____
3 fold
Afib increases the risk of dementia by ____
2 fold
Afib increases the risk of hospitalization by ____
2 fold
Afib increases the risk of mortality by ____
2 fold
What are the 3 forms of treatment for Atrial Fibrillation.
- Anticoagulation
- Rate Control
- Rhythm Control.
T or F: Strokes which occur in patients with Afib are less detrimental to QOL than patients who do not have Afib.
F
In atrial fibrillation, clots are able to form in the ____ due to pooling of blood.
Left Atrial Appendage
What scoring tool is used to estimate stroke risk in Afib patients.
CHA2DS2VASc Score
What scoring tool is used to estimate bleed risk in Afib patients on anticoagulants?
HASBLED Score
What does CHA(2)DS(2)VASC Score Stand For.
C: Congestive Heart Failure
H: Hypertension
A: Age >75
D: Diabetes Mellitus
S: Stroke
V: Vascular Disease
A: Age 65-74
Sc: Sex Category
Which Components of the CHADSVASc score are worth two points.
1) Age >75
2) Stroke History
What CHADSVASC score indicates anticoagulant treatment in atrial fibrillation.
2+ (men)
3+ (females)T
The HASBLED score is only validated for _____
Warfarin.
If patients have a CHADSVASc score greater than 2 (men) or 3 (females), _____ is recommended.
Oral Anticoagulation
______ are recommended over warfarin in patients with Afib.
DOACs.
When would warfarin be preferred over DOACs?
1) Moderate-Severe Mitral Stenosis
2) Mechanical Heart Valves.
Patients with an elevated CHADSVASc score and ESRD or dialysis should reasonably be initiated on ____ or ____
1) Warfarin
2) Apixaban
_____ is allowing patients to remain in atrial fibrillation but control the rate to control symptoms.
Rate Control
_____ rate control should be used for patients who are
asymptomatic AND have an ejection fraction >40%.
Lenient (<110 bpm)
____ rate control should be used for patients who are symptomatic or patients with EF <40%.
Strict rate Control (<80 BPM)
What rate control agents are generally first line?
Beta Blockers, Diltiazem, Verapamil.
What rate control agents are used first line for HFrEF?
1) Beta-blocker
2) Digoxin
What rate control agent should be used second line?
Amiodarone
Non-DHP CCB are ____ inhibitors. (think metabolism)
CYP3A4
Digoxin is a _____ substrate.
P-glycoprotein
What drugs increase digoxin concentrations.
Amiodarone, Dronedarone, Verapamil.
What patients require conversion to sinus rhythm?
- Hemodynamically unstable
- Symptomatic Despite Rate Control
- Inability to achieve rate control.
Two methods of cardioversion
- Chemical Cardioversion
- Direct Current Cardioversion. (DCCV)
Flecainide Drug Class
Class 1C Antiarrhythmic
Propafenone Drug Class
Class 1 C Antiarrhythmic.
Sotalol Drug Class
Class III Antiarrhythmic
What are the class II antiarrhythmics
Beta-Blockers
Dofetilide Drug Class
Class III Antiarrythmic
Amiodarone Drug Class
Class III Antiarrhythmic
Dronedarone Drug Class
Class III Antiarrhythmic
Ibutilide Drug Class
Class III Antiarrhythmic
What are the class IV antiarrhythmics?
Non-DHP CCB. (Verapamil and Diltiazem)
________ are membrane stabilizers.
Sodium Channel Blockers (Class I Antiarrhythmics.)
_____ extend the refractory period.
Potassium Channel Blockers (Class III) Antiarrhythmic
These antiarrhythmics effect depolarization _____.
Sodium Channel Blockers Class 1
These antiarrhythmics widen the QRS complex.
Class I Antiarrhythmics
These antiarrhythmics widen the QT interval.
Class III Antiarrhythmics
Which Antiarrhythmics are preferred for an EF <40%
Amiodarone
Dofetilide
Ibutilide
Flecainide Dose
50 mg BID (MDD=300 mg)
Propafenone Dosing
IR = 150 mg Q8H
ER = 225 mg BID.
Class IC Antiarrhythmics under go ____ metabolism.
CYP2D6
At what CrCl is dofetilide contraindicated?
20
Dofetilide dosing
500 mcg PO twice daily.
Sotalol is contraindicated at a CrCl below _____
40
Which antiarrhythmics require a 3 day hospital stay to monitor QT prolongation.
Sotalol and Dofetilide.
Which Class III Antiarrhythmic is contraindicated in HF and permanent AF.
Dronedarone.
Which Antiarrhythmics are first line in CAD?
- Dofetilide
- Dronedarone
- Sotalol.
Which Antiarrhythmic is first line in heart failure?
- Amiodarone
- Dofetilide.
