Atrial Fibrillation Flashcards
Atrial Fibrillation
Disorganized, rapid, and irregular atrial activation with loss of atrial contraction and with an irregular ventricular rate that is determined by AV nodal conduction
MC sustained arrhythmia
Atrial Fibrillation
AF in px <60 years old with the absence of clinical findings of other cardiovascular disease, related pulmonary disease or cardiac abnormalities
Lone AF
Defined by episodes that START SPONTANEOUSLY and STOP WITHIN 7 DAYS of onset
Paroxysmal AF
Often initiated by SMALL REENTRANT or rapidly firing foci in sleeves of atrial muscle that extend into the pulmonary veins (PV)
Paroxysmal AF
Present when AF episode either lasts > 7 days or requires termination by cardioversion
Persistent AF
Facilitated by STRUCTURAL AND ELECTROPHYSIOLOGIC ATRIAL ABNORMALITIES, particularly FIBROSIS that uncouples atrial fibers, promoting reentry and focal automaticity
Persistent AF
Lasted for ≥ 1 year when it is decided to adopt a rhythm control strategy
Long-standing Persistent AF
SIGNIFICANT FIBROSIS is usually present and it is difficult to restore and maintain sinus rhythm
Long-standing Persistent AF
Major Source of Thromboembolism and Stroke in AF
thrombus in the left atrial appendage
Arrhythmia induced by alcohol intoxication
Holiday Heart
Hallmark of AF
IRREGULARLY IRREGULAR PULSE
Management when the DURATION OF AF IS UNCLEAR or is known to be >48 h
anticoagulation must be commenced BEFORE cardioversion
Common practice in px who have NOT BEEN ANTICOAGULATED provided that they are NOT AT HIGH RISK FOR STROKE d.t. prior hx of embolic events, rheumatic mitral stenosis, or hypertrophic cardiomyopathy with marked left atrial enlargement
cardioversion within 48 h of the onset of AF
Drugs for Rate Control
B-blockers: metoprolol, bisoprolol, atenolol, esmolol, propranolol, carvedilol (Class II)
Non-dihydropyridine CCB: verapamil, diltiazem (Class IV)
Digoxin
Amiodarone
Dronedarone
Goal of acute rate control
Reduce the ventricular rate to <100/min –
If adequate rate control in AF is DIFFICULT TO ACHIEVE, further consideration should be given to restoring sinus rhythm
catheter ablation of the AV junction
right ventricular apical pacing
biventricular pacing or direct pacing of the His bundle
ANTICOAGULATION is warranted for px with
MS
HCOM
prior history of stroke
Anticoagulant required for patients with RHEUMATIC MITRAL STENOSIS or MECHANICAL HEART VALVES
Warfarin
Reversal agents of warfarin
fresh frozen plasma and vitamin K
Reversal agent of dabigatran
Idarucuzimab
Options for subjects WITH significant structural heart disease
Amiodarone (Class III)
Options for subjects WITHOUT significant structural heart disease
Class I sodium channel–blocking agents (e.g., FLECAINIDE, PROPAFENONE, DISOPYRAMIDE)
Can be administered to patients with CORONARY ARTERY DISEASE OR STRUCTURAL HEART DISEASE but have ~3% risk of inducing excessive QT PROLONGATION and TORSADES DES POINTES
Class III agents SOTALOL and DOFETILIDE
More effective in maintaining SINUS RHYTHM and can be administered to patients with HF and CAD
Amiodarone
CHA2DS2-VASc Score
determine the risk of having a stroke in the presence of AF
CHA2DS2-VASc Score
estimates risk of ischemic stroke in patients w/ non-rheumatic/non-valvular AF
CHA2DS2-VASc Score
C - CHF/LVD - 1 H - HPN (>140/90 mmHg) - 1 A2 - age >75 years - 2 D - DM - 1 S2 - prior stroke/TIA/thromboembolism - 2 V - vascular disease (prior MI, PAD, aortic plaque) A - 65-74 - 1 Sc - Female sex
Non-Valvular AF
Males
CHA2DS2-VASc Score - 0 - no antiplatelet/anticoagulant
CHA2DS2-VASc Score - 1 - anticoagulant (Class IIa)
CHA2DS2-VASc Score - 2 - anticoagulant (Class I)
CHA2DS2-VASc Score - 3 - anticoagulant (Class I)
Non-Valvular AF
Females
CHA2DS2-VASc Score - 0 - N/A
CHA2DS2-VASc Score - 1 - no antiplatelet/anticoagulant
CHA2DS2-VASc Score - 2 - anticoagulant (Class IIa)
CHA2DS2-VASc Score - 3 - anticoagulant (Class I)
Valvular AF (mechanical heart valves, moderate to severe MS)
Warfarin
Used for px with RECENT ONSET AF (<48 h) and with hemodynamic instability
Electrical cardioversion
