1. Differential Diagnoses Of SVT: Common EP Lab Techniques
Hongsheng M. Guo, MD
Park Nicollet Heart & Vascular Center
Minnesota, USA

2. SVT Ablations at Park Nicollet (2006-2010)

3. Systematic Approaches
Baseline findings
Tachycardia
Maneuvers during tachycardia
History

4. Baseline Findings Ventricular Preexcitation 15 10 86 3%
AVNRT
ORT AT
Ventricular Preexcitation 15 10 86 3
Dual AVN Pathways 55 6 8
Decremental VA conduction
AP response to para-His pace 18 17 83
<1
AP response to diff RV pace
VA Block > 600 ms 11 42 5
VA block with adenosine

5. HV = -15 ms
PPV for ORT=86%

6. AH Jump
PPV for AVNRT=86%

7. Decremental VA Conduction
>99% Nodal Respnse

8. RV Pacing at 700 ms
PPV for ORT, 5%

9. Adenosine

10. ParaHisian Pacing

11. AP Response

12. ParaHisian Pacing

13. ParaHisian Pacing Adjust current output (mA) Adjust catheter position
Watch morphology subtle change closely

14. ParaHisian Pacing
Schematic representation of response to para-Hisian pacing between conduction over the AV node alone (A), conduction over an accessory pathway alone (B), and conduction over the AV node and accessory pathway combined (C).
Source: Heart Rhythm 2005; 2: (DOI: /j.hrthm )

15. ParaHisian Pacing: Nodal Response

16. ParaHisian: AP Response
PPV for ORT, 83%

17. Differential RV Pacing
VA Index= VA (basal) – VA (apical)
Martinez-Alday, et al Circulation 1994;89:1060

18. Differential RV Pacing: Nodal Response

19. Posteroseptal AP
Martinez-Alday, et al Circulation 1994;89:1060

20. Systematic Approaches
Baseline findings
Tachycardia
Maneuvers during tachycardia
History

21. Tachycardia Characteristics%
AVNRT
ORT AT
Septal VA <70 ms 47
>99
<1
Eccentric A activation 31 76 24
SVT terminates with AV block 10 66 34
↑VA >20 ms w/ BBB 7
100
Development of LBBB 12 4 92
Induction with critical AH 55 91 8 1
SVT CL >500 ms 3 83 17
AV block during SVT 60 40

22. Septal VA <70 ms
Not ORT

23. Eccentric Atrial Activation
Not AVNRT

24. SVT: What’s the machanism?
ORT
AVNRT
Not sure.

25. What is this?

26. Quick Maneuver

27. SVT: What’s the mechanism?
ORT
AVNRT
Not sure.

28. Systematic Approaches
Baseline findings
Tachycardia
Maneuvers during tachycardia
History

29. RA Pacing During SVT

30. LA (CS) Pacing During SVT

31. RV Pacing During SVT

32. What is this patient trying to tell you?

33. SVT Induction

34. Which Statement is true?
VA activation is eccentric.
This is likely ORT.
AV accessory pathway is ruled out.
AV accessory pathway is not ruled out.

35. His Refractory PVC

36. His Refractory PVC

37. RV Pacing During SVT

38. True or not: Atrial tachycardia is ruled out?
A. True. B. False.

39. RV Pacing

40. RV Pacing: AT?

41. Is This AT?

42. Fusion During Right ORT
Fusion with ventricular overdrive pacing during orthodromic reentrant tachycardia in a patient with a right free-wall accessory pathway. Before ventricular overdrive pacing, the ventricles are fully depolarized by the tachycardia wavefront via the AV node. A: Ventricular overdrive pacing results in fusion between the pacing wavefront (black) and the tachycardia wavefront (white with black stippling). With continued pacing there is progressive fusion with increasing amounts of ventricular myocardium depolarized by the pacing wavefront. B: Retrograde limb of the tachycardia eventually is driven by the paced wavefront, and a stable collision point results. This stable point of collision is located below the His bundle and results in constant QRS fusion.
Source: Heart Rhythm 2011; 8:2-7 (DOI: /j.hrthm )

43. Fusion During Left Lateral ORT and AVNRT
First beat of stable morphology during ventricular overdrive pacing in a patient with (A) orthodromic reentrant tachycardia and a left lateral accessory pathway (B) atrioventricular nodal reentrant tachycardia (AVNRT). The stable collision point with a left lateral accessory pathway is above the His bundle and results in a fully paced QRS morphology because the pathway is far from the pacing site. Because the ventricles are part of the tachycardia circuit in orthodromic reentrant tachycardia, the tachycardia must be reset coincident with or before the first beat with a stable QRS morphology. In AVNRT, the first beat of stable morphology (= the end of the transition zone) is fully paced but does not reset the tachycardia circuit. The pacing wavefront must first penetrate the His bundle and lower common pathway before it resets the tachycardia circuit.
Source: Heart Rhythm 2011; 8:2-7 (DOI: /j.hrthm )

44. Fusion During ORT
A: Orthodromic reentrant tachycardia in a patient with a decrementally conducting septal accessory pathway. Atrial timing is delayed with the first beat of right ventricular pacing diagnostic of orthodromic reentrant tachycardia. The stimulation-to-atrial interval (SA) becomes fixed during the transition zone (TZ), two beats before SM1. B: Atypical atrioventricular nodal reentrant tachycardia. Atrial timing is not altered, and the SA does not become fixed until SM3 and SM4, respectively, well after the end of the TZ. F = fusion between pacing wavefront and tachycardia circuit; SM = beat of stable morphology.
Source: Heart Rhythm 2011; 8:2-7 (DOI: /j.hrthm )

45. Fusion During AVNRT
A: Orthodromic reentrant tachycardia in a patient with a decrementally conducting septal accessory pathway. Atrial timing is delayed with the first beat of right ventricular pacing diagnostic of orthodromic reentrant tachycardia. The stimulation-to-atrial interval (SA) becomes fixed during the transition zone (TZ), two beats before SM1. B: Atypical atrioventricular nodal reentrant tachycardia. Atrial timing is not altered, and the SA does not become fixed until SM3 and SM4, respectively, well after the end of the TZ. F = fusion between pacing wavefront and tachycardia circuit; SM = beat of stable morphology.
Source: Heart Rhythm 2011; 8:2-7 (DOI: /j.hrthm )

46. Michaud, G. F. et al. J Am Coll Cardiol 2001;38:1163-1167
Long RP SVT
Michaud, G. F. et al. J Am Coll Cardiol 2001;38:
Scatterplot showing the mean value {+/-} SD of the stimulus-atrial-ventriculo-atrial (S-A-VA) interval (ms) for patients with either ORT using a septal accessory pathway or atypical AVNRT

47. Michaud, G. F. et al. J Am Coll Cardiol 2001;38:1163-1167
Long RP SVT
Michaud, G. F. et al. J Am Coll Cardiol 2001;38:
Scatterplot showing the mean value {+/-} SD of PPI-TCL (ms) for patients with either ORT using a septal accessory pathway or atypical AVNRT

48. Michaud, G. F. et al. J Am Coll Cardiol 2001;38:1163-1167
RV Is In The SVT Circuit
Michaud, G. F. et al. J Am Coll Cardiol 2001;38:
Entrainment of orthodromic reciprocating tachycardia (ORT) using a right posteroseptal bypass tract from the right ventricular apex (RVA) at a cycle length of 440 ms

49. RV Is Not In The SVT Circuit
Michaud, G. F. et al. J Am Coll Cardiol 2001;38:
Entrainment of atrioventricular node re-entrant tachycardia (AVNRT) from the right ventricular septum (RVS) at a cycle length of 510 ms

50. A>B>E B A Entrainment Mapping m m TCL=24 hours
PPI=24 + 2xm hours A

51. What is the right diagnosis?
Typical AVNRT
Atypical AVNRT
ORT
Atrial tachycardia
Not sure

52. What is the right diagnosis?
A. VT
B. Atrial tachycardia
C. AVNRT
D. ORT (right AP)
E. ORT (left AP)
F. Not Sure

53. What’s the mechanism? 09705818 A. VT B. Atrial tachycardia C. AVNRT
D. ORT (right AP)
E. ORT (left AP)
F. Not Sure

54. Irregular AA During SVT

55. What’s the mechanism? AT
ORT
AVNRT
Not Sure

56. What’s the mechanism? AT
ORT
AVNRT
Not Sure

57. Single diagnostic pacing maneuver for supraventricular tachycardia George D. Veenhuyzen, MD, FHRS, Kelly Coverett, MD, F. Russell Quinn, MRCP, PhD, John L. Sapp, MD, Anne M. Gillis, MD, Robert Sheldon, MD, PhD, Derek V. Exner, MD and L. Brent Mitchell, MD
Source: Heart Rhythm 2008; 5: (DOI: /j.hrthm )

58. Rule-OUT AVNRT ORT AT Septal VA <70 ms X Eccentric A activation X*
SVT terminates with AV block
SVT terminates by V pcae with no A
SVT CL >500 ms
AV block during SVT
Induction with critical AH
SVT persists when V isolated
* Typical AVNRT

59. Rule-IN AVNRT ORT AT Septal VA <70 ms X ±
VA increase by >20 ms w/ BBB
SVT terminates by V pace during His ERP with no A
SVT CL >500 ms
True VAAV response

60. Step-by-step Systemic Approach
History
Vagal effect
Adenosine
Baseline
Delta waves, or other evidence of AP
Dual AVN pathway
VA conduction
Tachycardia
VA: time, sequence
BBB
Induction
AV block
Maneuvers
His premature
RV pacing: VAV or VAAV, PPI-TCL

61. The Famous Quotation: SVT的消融应精确，优雅，有品味，精美的艺术品。
“SVT ablation should be precise, elegant, and classy, an art work.
One should take every opportunity to fully appreciate all aspects before the dragon is killed.
Burning while learning certainly does not belong here!”
SVT的消融应精确，优雅，有品味，精美的艺术品。
每个人都应该利用一切机会充分欣赏各方面之前，龙被杀害。
燃烧的同时学习当然不属于这里！

62. Dragon ≠ 中国龙
LOST
IN TRANSLANTION!