Atrial Fibrillation TReatment Flashcards
What is it?
What is it?
Disorganized and irregular atrial electrical activity
“quivering”
occurs when atrial tissue is modified due to abnormalities in structure or function
Atrial Rate: 600-800 bpm
Ventricular rate: 100-180 bpm
or pt could have a somewhat normal heart rate
Arrythmia etiologies
Arrythmia etiologies
- causes of scarring or fibrotic tissue like..
a. Ischemic heart disease
b. cardiomyopathy
c. fibrotic diseases - changes to cardiac action potential like…
a. electrolyte abnormalities
b. drugs - other..
a. genetic diseases
Pathogenesis
Pathogenesis
Triggered by rapidly firing ectopic beats in the atria. ectopic beats can occur due to previously discussed etiologies of arryhtmias
Types of A fib
Types of A fib
Paraoxysmal: Terminates within 7 days of onset
Persistent: Last >7 days
Long standing: Last greater than 12 months
Permanent: pt and clinician have decided that there will be no more effort to restore or maintain sinus rhythm
Clinical Manifestations
Clinical Manifestations
Fatigue SOB palpitations hypotension Dizziness, lightheadedness syncope
many pts are asymptomatic and may not know they have A fib.
At increased risk for ..
At increased risk for ..
- stroke (5 fold increase)
- heart failure: 3 fold increase
- dementia: 2-fold increase
- hospitalization: 2 fold increase
- mortality: 2 fold increase in risk
- cost
a. pts have an increased cost of $87,000/ year
b. costs health care system $27 B annually
3 categories of treatment for Afib
- anticoagulation
- rate control
- rhythm control
Why Anticoagulate
Why Anticoagulant?
Strokes in pts with a fib are more detrimental than pts ho had strokes without A fib
clot can form in left atrial appendage due to pooling of blood in that area
anticoagulation can prevent clot from forming
CHA2DS2VASc Score
What is it used for
determine person with a fibs risk of stroke
CHA2DS2VASc Score
categories
Determine Risk of Stroke
CHA2DS2VASc Score
Congestive Heart Failure . 1 point Hypertension: 1point Age > 75: 2 Diabetes Mellitus: 1 Stroke/ tia/ systemic embolism: 2 points Vascular Disease (PAD, CAD, coratid vascular disease 1 point Age 65-74 1 point Sc: Sex category (female) 1 point
Anticoagulant:
- Males with CHA2DS2VASc Score >/= 2
- Females with with CHA2DS2VASc Score >/= 3
HAS BLED SCORE
Determine Risk of Bleeding if we were to anticoagulate a pt with A fib
chronic anticoagulation for afib
oral anticoagulants
- DOACS > warfarin
unless patient has mitral stenosis or mechanical heart valves, then warfarin preferred
apixaban
rivaroxaban
edoxaban
dabigatran
acute anticoagulation for afib
Heparin
LWMH
Fondaparinux (arixtra)
IV direct thrombin inhibitors
Why do rate control?
Why do rate control?
to regulate the ventricular heart rate during A fib, reduce or eliminate symptoms, improve hemodynamics, prevent HF, and reduce risk of adverse CV outcomes
Acute Vs Chronic Rate Control
Acute Vs Chronic Rate Control
Acute: generally use IV (bolus +IV)
and transition to oral (generally avoid BB +non DHP CCB but sometimes used if pt is monitored closely)
chronic: oral agents
may require multiple agents (generally avoid BB +non DHP CCB but sometimes used if pt is monitored closely)
Types of Rate control
Types of Rate control
- Lenient: Goal is HR <110 bpm
for patients who..
asymptomatic pts. AND EF> 40% - Strict rate control: Goal is HR < 80 bpm
for patient who are..
Symptomatic OR have EF<40%
Rate control Algorithm
if have no CV disease
first line: BB, Verapamil, diltiazem
second line: amiodarone
if HTN, or HFpEF
first line: BB, Verapamil, diltiazem
second line: amiodarone
if have LV dysfunction or HF
first line: BB (with mortality beenfit), Digoxin
second line: amiodarone
if have COPD
first line: BB, Verapamil, diltiazem
second line: NONE.
Why do Rhythm Control?
Why do Rhythm Control?
In studies, Rhythm control did not improve mortality compared to rate control, actually increased adverse events
but rhythm control is indicated in pts who…..
- Hemodynamically ustable
2 Symptomatic despite rate control
3.Inability to achieve rate control
Which method of should be used to conversion to sinus rhythm?
Which method of should be used to conversion to sinus rhythm?
- hemodynamically unstable
a. immediate cardio version - symptomatic despite rate control
- DCCV, chemical cardio version, or both - Inability to achieve rate control
- DCCV, chemical cardio version, or both
What is techniques are used for rhythm control
What is techniques are used for rhythm control
Two methods
1. Chemical cardio version
a. utilizes antiarryhthmic drugs to convert to sinus rhythm.
works 20-70% of the time
- Direct current cardioversion (DCCV)
a. utilizes a defribillator to shock the patients heart into normal sinus rhythm.
b. works almost 100% of the time, the trick is KEEPING them in sinus rhythm
acute rhythm control if it has been more than 48
- Delayed cardioversion with anticoag x3 week, then DCCV.
if pt is really sompotmatic and cant wait, do TEE to look for clot in left appendage of heart. if no clot, then can do DCCV, if there is, they have no choice to do delayed cardioversion
Acute rhythm control if < 48 hours
consider DCCV
if DCCV is unfeasible, undesireable, or unsuccessful,
if EF>40, use aiodarone, dofetilide, flecainide, ibutilide, propafenone
if EF<40%: amiodaarone, dofetilide
ibutilide
acute chemical csrdioversion drugs
Class I (sodium channel blockers): flecainide, propafenone
Class III potassium channel blockade. Amiodarone, dofetilide, ibutilide
chronic chemical cardioversion antiarrythmic drugs
Clas 1 sodium channel blockers: flecainide, propafenone
clas III. sotalol, dofetilide, dronedarone
