1. When Catheter Ablation Should Be First Line Therapy
Neil K. Sanghvi, M.D.

2. Unfortunately, this depicts the current state of affairs in the US.

3. Common Symptoms Palpitations (often sudden on & off) Anxiety
Light-headedness
Chest pain
Neck Pounding
Dyspnea
Polyuria in prolonged cases secondary to ANP release
Neck pounding is typically from canon A waves or pulsing carotids

4. 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
Paroxysmal junctional reciprocating tachycardia (PJRT)
Sinus node reentry

5. Cardiac Electrical System
SA Node
AV Node
His Bundle
Left Bundle
Right Bundle

6. 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
It is estimated that 10% of the general population may suffer from AVNRT
15% of the general population may exhibit dual AV-nodal physiology
60% of the general population may exhibit retrograde VA conduction via the AV node

7. Reentrant tachycardias
Usually precipitated by a PVC or PAC
May also occur secondary to:
Excessive caffeine intake
Alcohol intake
Recreational drug use
Hyperthyroidism
Exercise

8. Initial Workup History, history, history… 12 lead EKG Echocardiogram
Holter monitoring
Thyroid function
CBC (looking for anemia, infection)

9. 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)

10. 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.
α = slow pathway, β = fast pathway
Panel B: block occurs usually due to a premature beat
Reentry-most common mechanism: Represents a “short circuit” that forms between two “pathways” that are either anatomically or functionally distinct. Path 1: Slow conduction, short refractory period. Path 2: Rapid conduction, long refractory period

11. 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.

12. Short RP>PR tachycardias
AVNRT
AVRT
Junctional tachycardia
Atrial tachycardia with 1o AVB
Permanent junctional re-entrant tachycardia (PJRT) is a rare arrhythmia due to a concealed accessory pathway with decremental retrograde conduction properties

13. Long RP>PR tachycardias
Atrial tachycardia
Atypical AVNRT
Sinus Tachycardia

14. QRS morphology based on the mechanism of the tachycardia

16. 33yo with sudden onset of palpitations and SOB after driving from NY to FL.

17. Sinus Tachycardia
Note the classic S1Q3T3 seen with pulmonary emboli

18. 40yo with sudden onset of palpitations while mowing the lawn.

19. 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)

20. AVNRT Ablation – Catheter Position
HRA
His
Here is a schematic representation of catheter positioning for a typical slow-fast AVNRT AV node modification.
Abl

21. Triangle of Koch HB Tendon of Todaro CS Septal TV
The triangle of koch is the area of interest in AVNRT ablation. The area is defined by the 1. Tendon of Todaro, 2. the CS, and 3. the septal leaflet of the TV. The apex of the triangle is marked by the HB. The AV nodal “slow” pathway typically lies inferior to the HB and anterior to the CS os.

22. 31yo man presenting with palpitations after a night on the town.
Note certain R-R intervals that are ~ 300 BPM.
Mixture of “narrow” and “wide” complexes.

23. How would you treat this man?
Verapamil/Diltiazem
Beta Blocker
Adenosine
Digoxin
Procainamide/Amiodarone

24. Atrial fibrillation with Wolf-Parkinson-White
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

25. Baseline EKG for Previous Patient

26. EKG requirements to diagnose Pre-excitation (WPW)
P-R < 120ms
Delta wave
QRS > 100ms
Normal P-wave axis
Patients with WPW should be evaluated for their risk of sudden death
Typically, asymptomatic patients may be placed on a treadmill to determine whether they lose their preexcitation with higher HR (low risk)
Risk of SCD is high if accessory pathway is able to conduct faster than (250ms = 240bpm)
EP study only indicated if patient’s are symptomatic, h/o SCD, or in a high-risk profession

27. 72yo woman with history of HTN p/w palpitations and SOB.

28. 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

29. 66yo woman with rapid heart rate and anxiety.

30. 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

31. Activation on Halo Catheter During Typical Atrial FlutterII
aVF V1
CS Os
TA 1,2
TA 3,4
TA 5,6
TA 7,8
TA 9,10
TA 11,12
TA 13,14
TA 17,18
TA 19,20
TA 19,20
CS Os
TA 9,10
TA 1,2
Opening of the anterior RA. SVC upper left, IVC lower left, TV on right, fossa in the middle
Modified LAO view
Cavotricuspid isthmus is defined by the tricuspid valve annulus and IVC
Typical = CCW

32. Activation on Halo CatheterII
aVF V1
CS Os
TA 1,2
TA 3,4
TA 5,6
TA 7,8
TA 9,10
TA 11,12
TA 13,14
TA 17,18
19,20
TA 19,20
TA 9,10
CS Os
TA 1,2
Atypical = Clockwise

33. 3D Propagation Map of Atrial Flutter

34. Atrial Flutter CTI Ablation - LAO

35. Atrial Flutter CTI Ablation - RAO

36. 68yo woman with severe COPD exacerbation.

37. Atrial tachycardia with variable block
Atrial rates typically bpm
Often treated with AAD for rhythm control, nodal agents for rate control
Catheter ablation has success rates of > 80%

38. Atrial Tachycardia
Carto map revealing a focal atrial tachycardia originating from the SVC

39. 25yo man with fever of 102.

40. Sinus tachycardia

41. 65yo man presenting with palpitations.

42. 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

43. 2014 Guidelines

44. AF Success w/ Ablation
Device insertion
Pre- ablation
Post- ablation

45. Conclusion
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