Transcript Cardiac Arrhythmias and Conduction Abnormalities

Cardiac Arrhythmias and
Conduction Abnormalities
Andrew P. Wilper, MD
Goals and Objectives
• Diagnose common cardiac arrhythmias
 Discuss importance of, and indications for
anticoagulation in atrial fibrillation
• Diagnose common cardiac conduction
abnormalities
PART 1
We Are a Part of the
Rhythm Nation
You are seeing a 61-year-old man in urgent care. He complains of
light headedness. He denies chest pain and dyspnea.
ATRIAL FIBRILLATION
Irregularly irregular & undulating baseline
ATRIAL FIBRILLATION
Rule #1
Narrow and irregularly irregular is atrial fibrillation until proven
otherwise.
Why did it occur? MI? PE? Hyperthyroidism? ETOH?
Valvular Disease?
Treatment
Rate control: diltiazem, beta blocker, digoxin, ablation
Rhythm control? Generally no unless very poor output
Anticoagulation Embolic risk ~ 5%/year
CHADS2
points score NNT
CHF
1
0
417 Review VASc RF
HTN
1
1
125 Anticoagulation
Age > 75
1
2
81
Anticoagulation
DM
1
3
33
Anticoagulation
Secondary (TIA, CVA) 2
4
27
Anticoagulation
5/6
44
Anticoagulation
What about CHADS2=0?
• Consider use of additional risks in form of
CHA2DS2-VASc
– Gives two points for age 75 years and older
– An additional point for age 65-74
– An additional point for females
– An additional point for vascular dz (CAD, PVD)
– Better identifies risk among CHADS2=0 patients
Skanes. Can Jour Cardiol. 2012. 28, 125-136
RE-LY. NEJM. 2009
You are seeing a 44 yo female with a
complaint of palpitations.
Rate 180
QRS Morphology
when in sinus rhythm
What was the rhythm?
Supraventricular tachycardia
What was the treatment?
Adenosine IV
What is the problem?
Wolff-Parkinson-White
SUPRAVENTRICULAR TACHYCARDIA (SVT)
RATE
150-250 (typically ~ 180)
Why did it occur?
Accessory pathway?
ETOH?
Stimulants?
Treatment
Vagal Maneuvers
Adenosine (temporary A-V blockade)
Cardiovert if unstable
EPS w/ablation for WPW
Caffeine?
Common SVT Characteristics
MAT
Afib
Aflutter
WPW
Rate
Sinus
EAT
tachycardia
>100
100-180
>100
Vent rate:
125-175
140+
Regularity
Regular
Regular
Usually
regular
Sawtoothed
Irregular or
regular
Buried
1:1
Ectopic
focus
different
1:1
Irregularly
irregular
At least 3
different
morphologies
1:1
Variable
(can be fast
or slow)
Irregularly
irregular
None
None
Most
commonly
2:1, others
are 3:1 and
4:1
Variable
1:1 if you
can see it
P wave
P:QRS
ratio
PR interval Normal to
slightly
shortened
Ectopic
focus
with
different
interval
Variable
None
Very
shortened;
QRS is also
typically
wide
You are seeing a patient in the ED with
a complaint of palpitations. Recent
history of pericarditis.
Rate 150
ATRIAL FLUTTER
Flutter waves
ATRIAL FLUTTER
Rule #2
Narrow, regular, and 150 is atrial flutter until proven otherwise.
Why did it occur? CHF?
Recent Cardiac Surgery?
COPD?
Treatment
-Usually goes away or converts to A-fib
-Anticoagulation-similar approach to
atrial fibrillation
-Radiofrequency ablation of reentrant
circuit
Pericartidis?
FAST, NARROW RHYTHMS
Irregularly irregular (Rule #1)
A-FIB
Rate > Rhythm Control
(Remember MAT)
CHADS2
Regular at ~ 150 (Rule #2)
A-FLUTTER
Adenosine for diagnosis
Regular > 150
SVT Accessory pathway (ablation)
Adenosine for treatment
Stimulants
You are seeing a 61-year-old man in urgent care. He complains of
light headedness. He denies chest pain and dyspnea.
1. Abnormal and wide qrs (>120 ms) with secondary st and t
wave changes, qrs concordance in V1-V6
2. Rate 140-200
3. Regular or slightly irregular
4. Abrupt onset and termination
5. AV dissociation
6. Capture beats-regular qrs from atrial p wave
7. Fusion Beats-partial depolarization by atrial and ventricular
impulse
V – TACH
You are called to the bedside of a
patient with a history of drug-induced
long QT syndrome.
Diagnosis?
Polymorphic Ventricular Tachycardia
Polymorphic VT
1) Paroxysms of VT with irregular RR interval
2) Ventricular rate 200-250
3) Two or more cycles of qrs complexes with
alternating polarity
4) Changing amplitude of qrs complexes in
sinusoidal fashion
5) If prolonged QTc=Torsades de pointes
FAST, WIDE RHYTHMS
Ventricular Tachycardia
• QRS > 0.14 ms
• QRS concordance in V1-6
• Notching in V1 down stroke
SVT with LBBB
• deep S in V1, V2
• wide R in I, V6
• T-wave opposite terminal QRS
SVT with RBBB
• some R wave in V1
• prominent S in V6
• T-wave opposite in III, V1-3
WiLLiaM MaRRoW=W in V1 and
for M in V6 for LBBB, RBBB opposite
V tach-fusion beat
You are seeing a 61-year-old man in urgent care. He complains of
light headedness. He denies chest pain and dyspnea.
2o, Mobitz type I
(Wenckeback )
Grouped beating
Lengthening P-R interval
Dropped beat
APPROACH TO HEART BLOCK
(P = QRS) Are there as many P waves as QRS complexes?
NO
YES
1o
(P-R =) Is the P-R interval always equal?
NO
YES 2o, Mobitz II
(QRS =) Is the QRS interval always equal?
NO
2o, Mobitz I (Wenckebach)
YES
3o
Sinus Node Wenckebach (Sick Sinus)
0.10
0.10
0.86
0.10
0.82
Sinus Wenckebach
AV Wenckebach
SA
SA
A
A
AV
AV
V
V
54 year old male with intermittent dizziness
54 year old male with intermittent dizziness
Unchanging PR with
unexpected dropped beats
Diagnosis=Mobitz II Block
When to get help!
Name the Rhythm
You review the chart….
And find this
Name the Rhythm
Paced Rhythm
Motion Artifact
Aberrantly Conducted Native Beats
42 year old, screening physical
RBBB
1. QRS >0.12 sec (in ANY lead) – look for this first
2. Slurred S wave in I and V6 – look for this second
3. RSR’ pattern in V1 with R’ taller than R (“Rabbit
ears”)
4. Should be predominately positive in V1 – look for
this only AFTER looking for the previous 2 criteria
Right Bundle Branch Block
• Clinical Correlates-RVH, sudden increase in
right ventricular pressure with stretch (as in
pulmonary embolism), Cor Pulmonale,
myocardial ischemia, infarction, or
inflammation (myocarditis), hypertension.
• Caveats: Sometimes you will see a qR’ wave
indicating an anteroseptal MI in V1 (floppy
eared rabbit).
• You cannot diagnose RVH in RBBB
75 yo male presents to establish care, prior
history of lymphoma
LBBB
1. QRS duration >0.12 sec
2. Broad, monomorphic (meaning
all positive or all negative) R waves
in I and V6, with no Q waves
3. Broad, monomorphic S waves in
V1; may have small r wave
Left Bundle Branch Block
• Clinical associations: HTN, CAD, valvular heart
disease (rheumatic heart disease),
endocarditis, cardiomyopathy, infiltrative
diseases of the heart, prior XRT
• Caveats: You cannot Dx LVH or RVH in patients
with LBBB. Infarction is tricky to diagnose in
LBBB, but possible
Delays
• Intraventricular Conduction Delay (IVCD)
• Criteria:
– QRS duration > 0.12 seconds
– Doesn’t qualify for LBBB or RBBB
**When this is seen, look for hyperkalemia
Blocks
• Hemiblocks (Left Anterior Fascicular Block, Left Posterior Fascicular
block)
• A few words: The Left bundle splits into the left anterior fascicle and the
left posterior fascicle
Blocks
• Criteria:
• Left Anterior Hemiblock/Fascicular Block (fairly
common)
– LAD with axis at –30 to –90 degrees
– qR complex or an R wave in lead 1, AvL
– An rS complex in lead III and usually in II and aVF
– Easy shortcut: LAD?yes, then check lead II
– if net vector is negative LAHB
LAFB ECG
Axis?
Left
QRS
duration?
<120ms
Net Vector
in II?
Negative
Causes of LAFB
•
•
•
•
CAD
Hypertension
Valvular disease
Degenerative disease of the conducting
system
• Sclerosis of the left cardiac skeleton
• Myocardial fibrosis
• Normal Variant (2-5%)
Blocks
• Left Posterior Hemiblock/ Fascicular Block (fairly
rare)
– RAD with axis 90-180
– S wave in lead I and a q in III
– Exclusion of RAE and/or RVH
Left Posterior Hemiblock
Axis?
Right
QRS?
<120 ms
rS in I and
aVL
qR in III
and aVF
Causes of LPFB
•
•
•
•
•
•
Similar to LAFB
Cardiomyopathies
Chagas disease
Myocarditis
Hyperkalemia
Acute cor pulmonale
Note
• RBBB+LAFB or RBBB + LPFB commonly
referred to as bifascicular blocks
Practice!
Normal Sinus Rhythm
A fib w/BBB
VT
A Fib
LBBB
NSR with PAC
Rate related LBBB
LVH with strain
Sinus Tachycardia, A-V dissociation
RBBB
LAFB
NS ST/T abn
Thank you