Transcript When Cardiac Ablation Should Be First Line Therapy

When Catheter Ablation Should
Be First Line Therapy
Neil K. Sanghvi, M.D.
Common Symptoms
Palpitations (often sudden on & off)
 Anxiety
 Light-headedness
 Chest pain
 Neck Pounding
 Dyspnea
 Polyuria in prolonged cases secondary
to ANP release

Types of Supraventricular
Tachycardias
AVNRT (AV nodal reentrant
tachycardia)
 AVRT (AV reciprocating tachycardia)
 Atrial tachycardia
 Multifocal atrial tachycardia
 Atrial flutter
 Atrial fibrillation
 Junctional tachycardia
 Sinus tachycardia

Cardiac Electrical System
SA Node
AV Node
His Bundle
Left Bundle
Right Bundle
Frequency of various types of SVT
60% due to AVNRT (AV-nodal
reentrant tachycardia)
 30% due to AVRT (AV reciprocating
tachycardia)
 <10% due to atrial tachycardia

Reentrant tachycardias

Usually precipitated by a PVC or PAC
May also occur secondary to:
 Excessive caffeine intake
 Alcohol intake
 Recreational drug use
 Hyperthyroidism
 Exercise
Initial Workup
History, history, history…
 12 lead EKG
 Echocardiogram
 Holter monitoring
 Thyroid function
 CBC (looking for anemia, infection)

Observations From An EKG

Observe zones of transition for clues
towards the mechanism:
onset
 termination
 slowing, AV nodal block
 bundle branch block (what happens to
the cycle length of the tachycardia)
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Understanding Reentry
Panel A: Most impulses conduct down
both pathways.
Panel B: Unidirectional block, due to
longer refractoriness in one pathway.
Panel C: Potential to have reentry back up
the previously refractory pathway
Panel D: Reentry then can persist.
Orthodromic AVRT
A. Sinus impulses travel down
both the accessory pathway
and AV node.
B. Premature beat finds the
accessory pathway refractory
but is able to travel down the
AV node.
C. Impulses are able to traverse
the myocardium and find the
accessory pathway excitable
thereby sustaining the
tachycardia.
Short RP>PR tachycardias
AVNRT
 AVRT
 Junctional tachycardia
 Atrial tachycardia with 1o AVB

Long RP>PR tachycardias
Atrial tachycardia
 Atypical AVNRT
 Sinus Tachycardia

QRS morphology
based on the
mechanism of the
tachycardia
33yo with sudden onset of palpitations
and SOB after driving from NY to FL.
Sinus Tachycardia
 Note the classic S1Q3T3 seen with
pulmonary emboli

40yo with sudden onset of palpitations
while mowing the lawn.
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AVNRT
Look for “pseudo S-wave” in inferior leads and
“pseudo-R prime” in V1 which actually indicate
retrograde P-waves
Terminates with vagal maneuvers in 1/3 cases
Responsive to AV nodal blocking agents such as
beta blockers, CA channel blockers, adenosine.
Recurrences are the norm on medical therapy
Catheter ablation 95% successful with 1-2% major
complication rate (including heart block)
AVNRT Ablation – Catheter Position
HRA
His
Abl
HB
CS
Triangle of
Koch
31yo man presenting with palpitations
after a night on the town.
How would you treat this man?
A.
B.
C.
D.
E.
Verapamil/Diltiazem
Beta Blocker
Adenosine
Digoxin
Procainamide/Amiodarone
Atrial fibrillation with Wolf-ParkinsonWhite
 Never use nodal agents when
evidence of pre-excitation exists and
the accessory pathway is capable of
rapid conduction
 >95% cure rate for ablation of
accessory pathway
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Baseline EKG for Previous Patient
EKG requirements
to diagnose Preexcitation (WPW)
P-R < 120ms
Delta wave
QRS > 100ms
Normal P-wave
axis
72yo woman with history of HTN p/w
palpitations and SOB.
Atrial Flutter with variable block
 “Typical” since flutter waves are
negative in inferiorly and upright in
V1 which implies a right atrial
isthmus-related tachycardia

66yo woman with rapid heart rate and
anxiety.
Atrial flutter with 2:1 conduction
 >95% cure rate with catheter
ablation with a major complication
rate of < 1%
 Will be able to stop anticoagulation
within 1 month
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Activation on Halo Catheter During
Typical Atrial Flutter
V1
II
aVF
TA 1,2
TA 19,20
TA 9,10
CS Os
TA 1,2
TA 3,4
TA 5,6
TA 7,8
TA 9,10
TA 11,12
TA 13,14
Typical = CCW
TA 17,18
TA 19,20
CS Os
Activation on Halo Catheter
V1
II
aVF
TA 1,2
TA 9,10 TA 19,20
CS Os
TA 1,2
TA 3,4
TA 5,6
TA 7,8
TA 9,10
TA 11,12
TA 13,14
Atypical = Clockwise
TA 17,18
19,20
CS Os
3D Propagation Map of Atrial Flutter
Atrial Flutter CTI Ablation LAO
Atrial Flutter CTI Ablation RAO
68yo woman with severe COPD
exacerbation.
Atrial tachycardia with variable block
 Atrial rates typically 150 -250bpm
 Often treated with AAD for rhythm
control, nodal agents for rate control
 Catheter ablation has success rates of
> 80%
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Atrial Tachycardia
Carto map revealing a
focal atrial tachycardia
originating from the SVC
25yo man with fever of 102.
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Sinus tachycardia
65yo man presenting with palpitations.
Atrial fibrillation with rapid ventricular
response
 Typically managed with AAD or nodal
agents for rate control
 Ablation with success rates in the
70—75% range if no other risk
factors

2014 Guidelines
AF Success w/ Ablation
Pre- ablation
Post- ablation
Conclusion
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Most SVTs should be referred for ablation even
with a first occurrence since there is a high
recurrence rate (anywhere from 25-80%)
Ablation may be considered first line therapy for
certain AF patients – young, few to no
comorbidities, not interested in AAD
Frequent PVCs may be ablated with > 90% cure
VT should be referred for ablation if failing AAD