Download 2016 A_fib

Cardiac Arrhythmias
Name That Rhythm
Kathaleen Johnson DNP, CRNP, CCRN
Objectives
 Identify common arrhythmias that cause dyspnea
 List diagnostic tests used to determine the cause of
these arrhythmias
 Describe treatment options for these arrhythmias
Common Arrhythmias that Cause
Dyspnea
 PSVT (paroxysmal superventricular tachycardia)
 Atrial fibrillation
 Atrial flutter
 Heart blocks
 Ventricular arrhythmias
Let’s start with a normal
rhythm
Basics on Where to Start with
Interpreting ECG’s
 Rate
 Rhythm
 Intervals
 Axis
 Hypertrophy
 Ischemia or infarct
Normal Sinus Rhythm
www.uptodate.com
Implies normal sequence of conduction, originating in the sinus node and
proceeding to the ventricles via the AV node and His-Purkinje system.
EKG Characteristics:
Regular narrow-complex rhythm
Rate 60-100 bpm
Each QRS complex is proceeded by a P wave
P wave is upright in lead II & downgoing in lead aVR
Atrial Fibrillation
 Irregular rhythm
 Absence of definite p waves
 Narrow QRS
 Can be accompanied by rapid ventricular response
Atrial Fibrillation—causes and
associations
 Hypertension
 Hypertrophic cardiomyopathy
 Hyperthyroidism and
 COPD
subclinical
hyperthyroidism
 OSA
 ETOH
 CHF (10-30%), CAD
 Caffeine
 Uncommon
 Digitalis
presentation of ACS
 Mitral and tricuspid
valve disease
 Familial
 Congenital (ASD)
Demographics
 Common; 2.2 million people in the U.S.
 Male>Female
 Prevalence increases with age
 Leading cause of embolic CVA
 Associated with increased risk for heart failure and all
cause mortality
Work-Up
 CXR
 EKG
 TSH
 CMP
 CBC
 Troponin
 Echo
Management
 The first step is to determine whether the patient is
stable or not
 Look for any hemodynamic instability such as
hypotension, elevated heart rate, fevers
 Is the patient responsive?
 Are there any MS changes?
 Is the patient symptomatic or asymptomatic?
Rate versus Rhythm Control
There is no clear survival
benefit in rate versus rhythm
control
Rate-Control Strategy
Try rate control first for patients with persistent AF:
 Over 65
 With CAD
 With contraindications to antiarrhythmic drugs
 Unsuitable for cardioversion
 Without CHF
Rhythm-Control Strategy
Try rhythm-control first for patients with persistent AF
 Who are symptomatic
 Who are younger
 Presenting for the first time with lone AF
 Secondary to a treated/corrected precipitant
 With CHF
Treatment Options
Patients with PAF can be highly symptomatic:
Three main aims of treatment for PAF are to…
Suppress paroxysms of AF and maintain NSR
Control HR during PAF
Prevent complications
Treatment strategies include out-of-hospital initiation of
antiarrhythmic drugs approach
Patients with PAF carry the same risks of stroke and
thromboembolism as those with persistent AF
Acute-Onset AF
Acute-onset AF requires immediate
hospitalization and urgent intervention
Those at highest risk have a ventricular
rate greater than 150 BPM, ongoing
symptoms of chest pain, dizziness,
syncope, or critical perfusion
Classification of AF
 Initial event
May or may not
reoccur
 Paroxysmal
recurrent
symptomatic
asymptomatic
Onset unknown
spontaneous termination
<7 days & most often <48hrs
 Persistent
Not self-terminating
recurrent
Lasting >7 days or prior cardioversion
 Permanent
Not terminated established
Terminated but relapsed
no cardioversion attempted
Treatment Options
 Cardioversion: synchronized (w/QRS) delivery of
current to heart; depolarizes tissue in a reentrant
circuit; afib involves more cardiac tissue
 Antiarrhythmics: amiodarone, sotalol (Betapace),
multaq (dronedarone), Rythmol (propafenone), Tikosyn
(Dofetilide)
 AV Nodal blocking agents: Diltiazem, metoprolol
 Anticoagulation
 AV Nodal Ablation
Considerations before
Cardioversion
 if onset is within last 24-48 hours, may be able to
arrange cardioversion—use heparin around
procedure
 Need TEE if valvular disease, duration >48hrs (or
high risk of thrombus) prior to cardioversion
 If unable to definitely conclude onset of AF in last
24-48 hours: need 4-6 weeks of anticoagulation
prior to cardioversion, and warfarin for 4-12 weeks
after
Cardioversion
 Cardioversion is performed as part of a rhythm-control
treatment strategy
 There are two types of cardioversion: electrical (ECV)
and pharmacological (PCV)
 Cardioversion of AF is associated with increased risk of
stroke in the absence of antithrombotic therapy
 Not all attempts at ECV or PCV are successful
 Patient choice is important
Atrial fibrillation--management
 Rate control with chronic anticoagulation is
recommended for first line approach for majority of
patients; overall Afib is a stable rhythm
 Beta-blockers (propanolol and metoprolol) or Nondihydropyridine calcium channel blockers
(verapamil or diltiazem) recommended.
 Digoxin not recommended for rate control
 Anticoagulation: low molecular weight heparin and
then warfarin; can use aspirin for anticoagulation if
contraindication to warfarin, but not as effective
The Aim of Heart Rate Control
 Minimize symptoms associated with excessive heart
rates
 Prevent tachycardia-associated cardiomyopathy
 Digoxin monotherapy should be only used for older,
sedentary patients
 Perform a risk-benefit assessment to inform the
decision of whether or not to give antithrombotic
therapy
CHADS2 Score for Atrial Fibrillation
Stroke Risk
 Congestive Heart Failure
Yes +1
 Hypertension History
Yes +1
 Age >75
Yes +1
 Diabetes Mellitus History
Yes +1
 Stroke Symptoms
previously or TIA?
Yes +2
Recommendations for Anticoagulations
Score
Risk
Anticoagulation
Therapy
Considerations
0
Low
Aspirin
Aspirin daily
1
Moderate
Aspirin or Warfarin
Aspirin daily or
raise INR to 2.03.0, depending on
factors such as
patient preference
2 or greater
Moderate or
High
Warfarin
Raise INR to 2.03.0, unless
contraindicated
(e.g. clinically
significant GI
bleeding, inability
to obtain regular
INR screening)
CHADS2-VASC
 CHF/LV dysfunction
 1
 HTN
 1
 Age >75
 2
 DM
 1
 Stroke/TIA
 2
 Vascular disease
 1
 Age 65-74
 1
 Female
 1
HAS-BLED
 HTN
 1
 Abnormal renal/liver fx
 1 or 2
 CVA
 1
 Bleeding
 1
 Labile INR’s
 1
 Elderly >65
 1
 Drugs or alcohol use
 1 or 2
Coumadin (Warfarin)
 MOA: Vitamin K antagonist
 Half life: 20-60 hrs, peak effect 72-96 hrs
 Until recently was one of the most efficacious treatment
for stroke prevention
 Difficult to keep INR at a therapeutic range
Dabigatran (Pradaxa)
 MOA- direct thrombin inhibitor(anti-IIa)
 Half-life-12-17 hrs with nml CrCl >80mL/min; if CrCl
<30 ~27 hrs
 Peak effect- 2-3 hrs
 No routine laboratory testing is needed
 Dosing 75-150mg BID
 Renal dosing CrCl 15-30: 75mg BID, CrCl <15 not
defined
 To convert from warfarin, start when INR <2, to convert
from parenteral anticoagulant start 0-2 hr before next
scheduled parenteral dose
Rivaroxaban (Xarelto)
 MOA- Direct factor Xa inhibitor
 Half-life-9-12 hrs; 9-13 hrs in elderly and those with
CKD
 Time to peak effect-2.5-4 hrs
 Dosing-20mg once daily with food (activity lower if
fasting)
-15mg once daily if CrCL=30-49mL/min
-10mg once daily for DVT prevention
Apixaban (Eliquis)
 MOA-Direct factor Xa inhibitor
 Half-life-2hrs time to peak effect 3 hrs
 Dosing-5mg twice daily
-2mg twice daily for high risk (ARI)
ASA + Clopidogrel
Not indicated for anticoagulation
for stroke prevention
Atrial fibrillation--management
 Goal INR of 2.5 (2.0-3.0) with coumadin
 Rhythm control---second line approach, if unable to
control rate or pt with persistent sxs
 Can also consider radiofrequency ablation at
pulmonary veins
Follow-Up and Referral
Follow-up after cardioversion should take place at 1
month, and the frequency of subsequent reviews should
be tailored to the patient
Reassess the need for anticoagulation at each review
Referral for further specialist intervention should be
considered in patients…
In whom pharmacological therapy has failed
With lone AF
With EKG evidence of any underlying
electrophysiological disorder
Atrial Flutter
 Atrial rate 250-350/min
 Sawtooth pattern in II, III, AVF
 Usually 2:1 or higher AV block
 Normal QRS
Atrial Flutter- causes and
associations
 Atrial stretch, fibrosis, scarring
 Often seen with sinus node dysfunction
 Often seen with atrial fibrillation
 Same factors seen in atrial fibrillation
Atrial Flutter-assessment
 H & P—assess heart rate, sxs of SOB, chest pain,
edema (signs of failure)
 If unstable, need to cardiovert
 Echocardiogram to evaluate valvular and overall
function
 Check TSH
 Assess onset of sxs—in the last 24-48 hours? Sudden
onset? Or no sxs?
Atrial flutter-management
 Control ventricular rate (beta blockers, calcium
channel blockers)
 Cardioversion
 Anticoagulation as with atrial fibrillation
 Ablations
Diagnostic Testing for Arrhythmias
 TSH
 Electrolytes
 Cardiac enzymes
 Hemodynamics
 Echocardiogram
 Cardiac catheterization
 Electrophysiology studies
CASE STUDY #1
 77 year old female who presented to the emergency
room with acute shortness of breath and chest
discomfort
 She has a history of prior CVA, HTN, Hypothyroidism,
Dyslipidemia, GERD
 Medications: Simvastatin, Aspirin, Lisinopril, Omeprazole
WHAT SHOULD BE DONE NEXT?
Diagnostics?
 Electrocardiogram
 Cardiac enzymes
 TSH
 BMP, CBC
 Urinalysis
 CXR
ECG INTERPRETATION
 Rate
 Regular or irregular….P waves?
 QRS wide or narrow?
Results/ECG interpretation
 Troponin 0.06 with nml CK, MB, RI
 Nml BMP, TSH
 WBC 11.2
 UA positive for leukocytes, WBC, nitrates
 CXR nml
 ECG…..???
 VS: temp 37.9, HR 125bpm, BP 136/82, RR 22, no
audible heart murmur
Management of AF
 3 main objectives
Rate control
Prevention of thromboembolism
Correction of rhythm disturbance if indicated
Treatment Options?
 Rate control versus antiarrhythmic? What do you
think?
 Anticoagulation? What is her CHAD2 Score
 Safety and monitoring?
 Other necessary testing?
CHADS2 Score
4
Continued….
 Duration of time in atrial fibrillation appears to be less
than 48hrs
 Given her age we could try converting with an
amiodarone drip
 Options for AC….coumadin versus another
anticoagulant…if indicated
 Further work up should include an echocardiogram and
possibly a nuclear stress test
Results/ECG Interpretation
 K+ 4.3, Mg 2.1, CK 124, MB 3.7, Troponin 0.23
 WBC 11, BUN 21, Cr 1.4
 TSH .67
 BNP 146
 CXR mild CHF
 ECG ???
 VS: 98/62, 132, 32, oxygenating 97% on 2L
QUESTIONS??
References
 www.uptodate.com
 Hebbar, A. Kesh and William J. Hueston, M.D. “Management of
Common Arrhythmias: Part I Supraventricular Arrhythmias,” Am
Fam Physician 2002; 65: 2479-86.
 Hebbar, A. Kesh and William J. Hueston, M.D. “Management of
Common Arrythmias Part II: Ventricular Arrythmias and
Arrhythmias in Special Populations,” Am Fam Physician 2002;
65:2491-6.
 Tallia, Alfred et al. “Swanson’s Family Practice Review” Fifth
Edition, Mosby, Inc. 2005, pp. 74-76.
 ABFM In-Training Exam 2002, 2003.
Multaq (Dronedarone)
 Indicated for patients with a recent episode of non
valvular paroxysmal or persistent atrial fibrillation or
atrial flutter and is in a NSR or will be cardioverted
 Contraindicated in HYHA Class IV CHF, recent
decompensated HF, Heart blocks, bradycardia, QTc
>500ms or PR >280ms,
severe hepatic impairment and pregnancy