Transcript The need for cardioversion - Calgary Emergency Medicine

ATRIAL
FIBRILLATION

An overview by: Matt Hall

Preceptor: Dr Lester Mercuur
Acute Management of AF:
A three-part approach to the acute management of
AF should be considered:
• Appropriate control of the ventricular rate.
• The need for, proper timing of, and the appropriate
method for the
restoration of sinus rhythm.
• The need for anticoagulation to prevent thromboembolism.
Order of Algorithm:







Haemodynamic stability
Assess state of hydration
Ventricular Rate Control
Clinical category of AF
Risk-stratifying the cardioversion decision
Anticoagulation considerations
Disposition decisions
Introduction






Most common sustained arrhythmia
More prevalent in men and with increasing age
Overall prevalence of AF is 1%. 70% are at least 65
years old and 45% are over 75
Prevalence ranges from 0.1% in adults <55 to
9%in those >80
AF uncommon in infants and children, almost
always occurring with structural heart disease
Accounts for >5% cardiac admissions
Classification


LONE AF:AF without structural heart disease
PAROXYSMAL AF: Self terminating AF in which the
episodes of AF last <7 days (usually <24hrs) and
may be recurrent

PERSISTENT AF: Not self terminating and last >7
days

PERMANENT AF: AF lasting >1 year and
cardioversion has failed or not been attempted
Etiology: Cardiac









Hypertension (1.5x)
Coronary heart disease (6-10%)
Rheumatic heart disease (16-70%)
CHF (10-30%)
Cardiomyopathy (10-28%)
Myocarditis
Post cardiac sx (30-60%)
Pericarditis
Congenital heart disease
Etiology: Non Cardiac








Hyperthyroidism (20-25%)
Pulmonary embolism (10-14%)
Obstructive sleep apnea
Noncardiac surgery (4.1%)
Alcohol (60% binge drinkers-”holiday heart”)
Caffeine
Hypothermia
Medications (theophylline)
Symptoms and Signs









Palpitations
Fatigue
Presyncope/syncope
Dyspnea/Chest Pain
Neurologic Deficit
Irregularly irregular HR
Absent a wave in JVP
Variable S1
Murmur
Evaluation

History and Physical:
Define symptoms
Clinical type
Onset of discovery of AF
Frequency/duration of AF episodes
Precipitating Causes
Modes of termination
Response to drug therapy
Presence of heart disease/reversible cause
Evaluation con’t

ECG: Verify presence of AF
Identify LVH
Pre-excitation
BBB
Prior MI
P wave duration and morphology
Measure intervals RR,QRS, QT
AF with pre-excitation
AF with pre-excitation
AF with pre-existing BBB
Differences:

Pre-excitation:
– Varying QRS width
and morphology

Existing BBB:
– Identical QRS
morphology
Evaluation con’t




Laboratory:CBC
INR/PTT
Electrolytes
Creatinine
TSH
CXR
Echocardiogram
Additional: TEE, Holter, Stress test, Cardiac
Catheterization, EPS
Acute Management of AF:
A three-part approach to the acute management of
AF should be considered:
• Appropriate control of the ventricular rate.
• The need for, proper timing of, and the appropriate
method for the
restoration of sinus rhythm.
• The need for anticoagulation to prevent thromboembolism.
RATE VS RHYTHM CONTROL
Favours rate control
 Persistent AF
 Recurrent AF
 Less Symptomatic
 >65 years old
 Hypertension
 No Hx CHF
 Previous antiarrythmic
drug failure
 Patient preference
Favours Rhythm Control
Paroxysmal AF
First episode AF
More symptomatic
<65 years old
No hypertension
Hx of CHF
No previous failure of
antiarrythmic drugs
Patient preference
Order of Algorithm:







Haemodynamic stability
Assess state of hydration
Ventricular Rate Control
Clinical category of AF
Risk-stratifying the cardioversion decision
Anticoagulation considerations
Disposition decisions
ATRIAL
FIBRILLATION
Unstable primarily due to the arrhythmia.
Ø
Hemodynamic instability
Ø
Unstable angina/Acute MI
Ø
Pulmonary edema
Ø
Pre-excited AF (WPW)
Hemodynamically stable
Exclude WPW. Intravenous AV-blocking
agents are contraindicated
Ø
UF heparin IV bolus and infusion
OR LMWH
Immediate electrical cardioversion
Admit
Warfarin x 4/52
Ø
Ø
Ø
Rate Control
(See Table 1)
PERMANENT AF
NEW ONSET AF OR RECURRENT PAROXYSMAL AF
Assumes hemodynamically stable and rate controlled
Therapeutic INR
Sub therapeutic
INR
Discharge *
LMWH and titrate
warfarin dose *
AF PRECIPITATED BY AN IDENTIFIABLE
CONDITION:
- ethanol intoxication
- hyperthyroidism
- sepsis
- acute MI/PE
- other
Treat underlying
condition
Consider heparin or
LMWH
NO TO ALL
(and AF < 48 hours)
Consider single dose LMWH
x 24 hours
Cardioversion:
Electrical :
- procedural sedation
- 100J/200J
Pharmacologic:
(See Table 2 )
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Is ANY ONE of the following present?
Duration of AF>48 hours
Duration of AF unknown
Severe LV dysfunction: LVEF <40%
Mitral valve disease
Previous arterial embolism
(CVA/TIA/peripheral arterial embolism)
YES TO ANY
#
Use either TEE -GUIDED STRATEGY OR CONVENTIONAL STRATEGY
if cardioversion is indicated;
TEE-GUIDED STRATEGY:
Unfractionated heparin or
LMWH and obtain TEE *
Clot
CONVENTIONAL STRATEGY:
LMWH + Warfarin initiation.
Anticoag x 3/52 *
No
Clot
Consider oral anticoagulation in high
risk pts
*
New-onset AF may need
further investigation *
Cardioversion:
Electrical:
- procedural sedation
-200J/360J
Pharmacologic:
(See table 2 )
Elective electrical or pharmacologic
cardioversion in 3/52
Consider repeat TEE prior to
cardioversion
Warfarin x 1 month
Warfarin x 1 month
Consider long-term warfarin in selected patients
(See table 3 )
Consider long-term warfarin in selected
patients ( See table 3 )
# Patients who fall into this group AND who have had a therapeutic INR for at least the preceding three weeks deviate from the
algorithm at this point; and the physician may proceed with cardioversion if it is indicated. Ensure continued anticoagulation.
*
denotes points in the algorithm where referral to an outpatient clinc may be indicated
Ventricular rate control:




Beta-Blockers
Calcium Channel Blockers
Digoxin
(Amiodarone)
WHICH ONE??


Beta Blockers
High adrenergic tone (eg post-op AF)
Good choice if ventricular response increases
excessively during exercise
Exercise induced angina
Setting of acute MI or Heart Failure
Thyrotoxicosis
Calcium Channel Blockers
No structural heart disease
COPD
Which One??
Digoxin
Usually ineffective alone (NOT 1st Line)
Synergistic with other drugs
LV Dysfunction +/- CHF
Amiodarone
Effective for rate and maintenance of sinus
rhythm after cardioversion (but at what cost)
Acute Management of AF:
A three-part approach to the acute management of
AF should be considered:
• Appropriate control of the ventricular rate.
• The need for, proper timing of, and the appropriate
method for the
restoration of sinus rhythm.
• The need for anticoagulation to prevent thromboembolism.
The need for cardioversion:
- Clinical category
A wide clinical spectrum exists:
- Asymptomatic to life-threatening
- Paroxysmal vs. chronic/permanent AF
- Normal heart vs. Diseased heart
- Risk of stroke
The need for cardioversion:
- Considerations
The frequency of the paroxysms of AF;
the severity of the associated symptoms, and the
degree of underlying heart disease
all need to be considered when determining the need to
restore and maintain sinus rhythm.
The need for cardioversion:
AF Spectrum
Normal
heart
Infrequent episodes
with severe symptoms
Paroxysmal
Diseased heart
with poor LV
function
Frequent asymptomatic
paroxysms
Persistent/Permanent
The need for cardioversion:
An attempt at cardioversion is reasonable with:
• lone AF (< 65 years with structurally normal hearts)
• first episode/ new onset AF
• patients who are very symptomatic during AF despite
adequate ventricular rate control
• patients with infrequent symptomatic paroxysmal atrial
fibrillation.
The need for cardioversion:
Patients with minimal symptoms; and in whom factors
have been identified which make cardioversion and
maintenance of sinus rhythm less likely, may benefit from
ventricular rate control and anticoagulation alone.
Need for Urgent Cardioversion





Ischemic Chest Pain
Acute MI
Hypotension
Pulmonary Edema
Syncope
The timing of cardioversion:
Key to the timing of cardioversion is the risk of thromboembolism.
The timing of cardioversion:
Factors associated with increased thromboembolic risk:
• AF > 48 hours in duration or unknown duration.
• Valvular heart disease – particularly mitral valve disease
• Significant LV dysfunction (LVEF < 40%) or
clinical heart failure
• Previous CVA/TIA/peripheral arterial embolism
• Hyperthyroidism
• Atrial Septal Defect (even if repaired)
NO TO ALL
(and AF < 48 hours)
Consider single dose LMWH
x 24 hours
Cardioversion:
Electrical :
- procedural sedation
- 100J/200J
Pharmacologic:
(See Table 2 )
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Is ANY ONE of the following present?
Duration of AF>48 hours
Duration of AF unknown
Severe LV dysfunction: LVEF <40%
Mitral valve disease
Previous arterial embolism
(CVA/TIA/peripheral arterial embolism)
YES TO ANY
#
Use either TEE -GUIDED STRATEGY OR CONVENTIONAL STRATEGY
if cardioversion is indicated;
TEE-GUIDED STRATEGY:
Unfractionated heparin or
LMWH and obtain TEE *
Clot
CONVENTIONAL STRATEGY:
LMWH + Warfarin initiation.
Anticoag x 3/52 *
No
Clot
Consider oral anticoagulation in high
risk pts
*
New-onset AF may need
further investigation *
Cardioversion:
Electrical:
- procedural sedation
-200J/360J
Pharmacologic:
(See table 2 )
Elective electrical or pharmacologic
cardioversion in 3/52
Consider repeat TEE prior to
cardioversion
Warfarin x 1 month
Warfarin x 1 month
Consider long-term warfarin in selected patients
(See table 3 )
Consider long-term warfarin in selected
patients ( See table 3 )
# Patients who fall into this group AND who have had a therapeutic INR for at least the preceding three weeks deviate from the
algorithm at this point; and the physician may proceed with cardioversion if it is indicated. Ensure continued anticoagulation.
*
denotes points in the algorithm where referral to an outpatient clinc may be indicated
The timing of cardioversion:
Patients who have
- any risk factors,
- or when there is doubt about the risk
need measures to ensure the absence of LA thrombus
before cardioversion is attempted.
For those with a sub-therapeutic INR, the TEE-guided
strategy or the conventional strategy of delayed
cardioversion is recommended.
The timing of cardioversion:
Patients who are already on warfarin; and who
have had a therapeutic INR for at least the
preceding three weeks, may undergo cardioversion
in the emergency department if indicated.
The timing of cardioversion:
Patients who have no risk factors, and who have AF < 48
hours (preferably <24 hours) in duration, may undergo
immediate cardioversion without the need exclude LA
thrombus
Electrical Cardioversion



Have all supplies needed (Monitors ,IV, Intubation
equipment, extra staff..etc)
Premedicate
Synchronized cardioversion (100,200,300,360J)
Drugs For Conversion of AF
CCS Consensus





Ibutilide (Level of evidence A)
Flecainide (A)
Procainamide (B)
Propafenone (A)
Amiodarone (B)
So what is the real danger?
Acute Management of AF:
A three-part approach to the acute management of
AF should be considered:
• Appropriate control of the ventricular rate.
• The need for, proper timing of, and the appropriate
method for the
restoration of sinus rhythm.
• The need for anticoagulation to prevent thromboembolism.
Stroke and AF:
Disabling stroke is the most devastating
complication of AF
Age, hypertension and previous stroke/TIA are the
strongest predictors of ischemic stroke in patients with
intermittent and sustained AF.
Stroke and AF:
The risk of stroke is the same in intermittent AF and
permanent AF.
The risk of thrombo-embolism does not differ between
electrical or pharmacological cardioversion
Spontaneous cardioversion is also associated with
thrombo-embolic risks.
Risk of stroke:
AF Spectrum
Normal
heart
Young
No additional stroke
risk factors
Diseased heart
with poor LV
function
Advanced age
Numerous other additional
stroke risk factors
Recommendations for long-term antithrombotic therapy in AF:
High risk criteria
- age > 75 years
- hypertension
- previous
stroke/TIA
- previous
systemic
embolism
- LVEF< 40%
- Rheumatic mitral
valve disease
- Prosthetic valve
Moderate risk criteria
- age 65-75 years
- diabetes mellitus
- CAD with
preserved LV
function.
Low risk criteria
- age <65 years
- no clinical or
echocardiographic
evidence of
cardiovascular disease
ANY High risk criterion - Warfarin therapy
TWO or more Moderate criteria - Warfarin therapy
ONE Moderate risk criterion - Warfarin therapy or Aspirin
LOW risk criteria - Aspirin therapy 325mg
Bottom line:





Treatment should be carefully tailored to individual
circumstance.
Not all patients need cardioversion
Defined role for attempting cardioversion
When there is doubt about thrombo-embolic risk,
cardioversion should be deferred
Anticoagulation recommendations reduce the
burden of ischemic stroke
ATRIAL FIBRILLATION DISPOSITION PATHWAY
Inpatient
AFIB in the ED
* Unstable
* CHF
* MI/ACS
* PE/hyperthyroid/sepsis
* Significant comorbid illness
ADMIT
Consult CCU Resident
or IM Resident if AFIB precipitated by
an identifiable condition
Outpatient
Needs initiation of outpatient
anticoagulation
Candidate for long term anticoagulation
(see table 3)
* Anticoagulation prior to delayed cardioversion
And
*
Needs further investigation
or treatment
Or
Yes
* Rate Control Only
* No known structural or ischemic
heart disease
No
Yes
* significant comorbid conditions
Refer to Anticoagulation Management
Services (AMS) Clinic
AND/OR
*:
FAX:
* ED Chart
* AFIB Order Set & Discharge Summary
* AMS Referral Form
Discharge patient back to Primary Care MD
COPY:
* ED Chart
*AFIB Order Set & Discharge Summary
Refer to Urgent Assessment Clinic or
to primary internist
FAX:
* ED Chart
* AFIB Order Set & Discharge Summary
* Urgent Assessment Form
* Requires rhythm control
* For delayed cardioversion
* High risk AFIB (previousTIA/CVA,
peripheral emboli)
* Structural heart disease
* Significant symptoms despite rate
control
Consult Cardiologist on Call or refer
back to primary cardiologist
FAX:
* ED Chart
* AFIB Order Set & Discharge Summary
* THE AMS Clinic is designed for the management of heparin and coumadin. It is NOT intended for further
investigation or treatment of AFIB. ALL AFIB patients MUST have follow-up arranged with the appropriate service.
AF Order Set and Discharge
Summary

Order Set
– Physician orders; Labs
–
–

Nursing interventions
Drugs and dosages
Discharge Summary
– Referral tool to Cardiology/ Internal Med/ Family
Physician
Cases


35 yo male with AF with rapid Ventricular response
following an alcoholic binge. C/O palpitations x 3
hrs. Never before.
88 yo female with significant CHF hx/+HTN
Presents with increased SOB. Hx AF….has been on
many drugs and shocked few times in past.
Coumadin in past. HR hasn’t been a problem for
sometime. Denies CP/Palp. Current meds include
Lasix, Carvediol, Ecasa, Digoxin, Altace. ECG shows
AF rate 135, no ischemic changes. CXR looks wet.
Cases

75 yo female with CAD Hx, DM, HTN presenting
with cough/SOB. Denies CP. CXR shows RLL
pneumonia and ECG shows AF rate 125. Meds:
ECASA 81, Metoprolol 50 bid, Metformin 500 tid
Cases

69 yo 100 kg male, sweaty, diaphoretic c/o chest
pain. AF present at rate of 150. Cardioversion not
successful. Patient is deteriorating…what now??
Cases


70 yo male c/o SOB, CP, diaphoresis. No CAD hx.
Has had HTN x many years and hx AF with previous
stroke. Meds include Atenolol, water pill, and
coumadin. ECG shows AF with rate of 120 and ST
elevation inf leads. INR 1.4
70 yo male presents with typical Anginal pain with
CAD hx. Has had HTN, MI and AF. Meds include Bblocker, Ace, Ecasa 81, Coumadin, Statin. Ecg
shows AF with rate of 145 but no ischemic changes.
INR 1.3
Note





In absence of a reversible cause, AF is usually
recurrent(75% with no antiarrythmic drugs)
AF begets AF (electrical remodeling) ? ACE
A persistent rapid rate can result in tachycardia
induced cardiomyopathy
Rate control should be assessed at rest and with
exercise
In patients with rapid ventricular rate with preexcitation over an accessory bypass tract (WPWS)
administer IV procainamide or ibutilide or perform
DC cardioversion if unstable (avoid B blockers ,Ca
Blockers, adenosine, digoxin)
THE END