Atrial Fibrillation Flashcards
What is the most common SUSTAINED arrhythmia?
Atrial Fibrillation
What are the characteristics of Atrial Fibrillation?
- Disorganized
- Rapid
- Irregular atrial activation
With irregular ventricular rate that is determined by?
AV Nodal conduction
In AF, prevalence increases with age with?
95% over the age of 60 years old
Prevalence by age of 80?
10%
Lifetime risknof developing AF among MEN at the age of 40 years?
25%
Prevalence of AF by Sex
Men > Women
Prevalence of AF by race
Whites > Blacks
AF accounts in ______% of strokes
25%
AF increases risk of _________ and _______ detected by MRI
Dementia and Silent Stroke
AF episodes that SELF-TERMINATE or cardiovert in < 7 days
Paroxysmal AF
AF episodes that DO NOT self terminate in less than 7 days?
Persistent AF
Persistent AF of >1 year
Long Standing AF
Efficacy of Anti-arrhythmic drugs is often effective at what kind of AF?
Paroxysmal AF
Clinical presentation and manifestation of AF results from?
- Irregular and often rapid ventricular rates
- Hemodynamic changes with altered cardiac function
- Effects of cardioembolic phenomena
General pathophysiologies of AF
- Loss of atrial contribution to ventricular filling
- Rapid Ventricular rates
In AF, Loss of atrial contribution to ventricular filling and Rapid Ventricular rates will result to?
Predisposition to thrombus formation at the LEFT ATRIAL APPENDAGE with risk of EMBOLIZATION
If patient with AF has impaired cardiac function (E.g HOCM, HF with preserved EF) this will lead to?
- Rapid ventricular rate
- Heart Failure
AF terminating to sinus rhythm can cause pauses that can lead to?
Dizziness or syncope
Seeb in ventricular rate of >100bpm among asymptomatix patients (no palpitations)
Tachycardia related - CMP
Tachycardia related CMP is reversible if we control the?
Ventricular rate
AF treatment aims to
- Control symptoms through rate control and/or rhythm control
- Mitigation of thromboembolic risk
- Addressing modifiable risk factors for progression of AF
What are the option if patient had unstable acute onset AF (Severe hypotension, pulmonary edema)
- Electrical cardioversion of 200J
- Pharmacologic cardioversion of IV ibutilide
IV Ibutilide is avoided in patients with ___________ or _________given the risk of torsades de pointes
- Baseline prolonged QT interval
- Severe LV dysfunction
In stable AF what would be the interventions?
- Rate control
- Anticoagulation to decrease stroke risk
AF duration is unclear or > 48 hours what whould be the management?
Anticoagulation before cardioversion
In AF what is the major source of thromboembolism and stroke?
Left atrial appendage thrombus
Despite successful cardioversion of prolonged AF, thrombi can still form as _______________ can be delayed for weeks
Atrial Mechanical Function
Cardioversion in the absence of anticoagulation may be done if low risk for thromboembolism (No prior embolic episodes, not rheumatic MS or HCMP with marked LAE) in AF of?
<48hrs
2 approaches to mitigate risk related to cardioversion
- Anticoagulate continuesly for 3 weeks and a minimum of 4 weeks after cardioversion
- Start anticoagulation and do TEE to check thrombus in LA appendage
If TEE was done and no thrombus was seen in the LA appendage what would be the management
Cardiovert then anticoagulate in >=4 weeks to allow recovery of atrial function
Choice of rate control in Acute AF
- BB and/or Non DHP CCB (IV or Oral)
- May add digoxin if with heart failure
Goal: <100bpm
Choice of rate control in Chronic AF
Beta blockers and/or Non-DHP may add Digoxin if with HF
Goal of controlling HR in Atrial Fibrillation
- Resting HR of <80bpm that increases to <100bpm with LIGHT EXCERSION (e.g walking)
- Resting HR of <110bpm if no symptoms + normal ventricular function
In Chronic AF, if adequate control is not achieved what would be the next step?
May consider restoring to sinus rhythm by catheter ablation + placement of permanent pacemaker
Stroke Prevention in AF
Anticoagulation
