Electrophysiology study protocol

Minimum protocol for Electrophysiology study of conduction in heart.

1. EP STUDY MINIMUM PROTOCOL

2. WE’VE TALKED ABOUT… EQUIPMENT PATIENT PREPARATION RELEVANT ANATOMY CATHETERS and PLACEMENT BASIC INTERVALS TESTS OF SN FUNCTION

3. AND NOW… EQUIPMENT PATIENT PREPARATION RELEVANT ANATOMY CATHETERS and PLACEMENT BASIC INTERVALS TESTS OF SN FUNCTION ATRIAL and VENTRICULAR EXTRASTIMULUS TESTING REFRACTORY PERIODS ‘GAP’ INCREMENTAL PACING MINIMUM PROTOCOL FOR DIAGNOSTIC EPS

4. Extrastimulus testing

5. 5 Drive train with a single extra stimulus 8 paced beat drive train – EP steady state Extrastimulus ( Coupling interval)

6. Extra stimuli S1 S1 S1 S1 S1 S1 S1 S1 S2 Sensed DRIVETRAIN S 1 S 1 S 1 S 1 S 1 S 1 S 1 S 1 S2 Sensed DRIVETRAIN S3 Single Double Triple

7. Atrial Extrastimulus testing Dynamic properties of AVN and HPS conduction AVN and RA refractory periods

8. Atrial Extrastimulus testing Dynamic properties of AVN and HPS conduction AVN and RA refractory periods Dual AVN physiology

9. Atrial Extrastimulus testing Dynamic properties of AVN and HPS conduction AVN and RA refractory periods Dual AVN physiology Arrhythmia induction

10. S2 with long coupling interval Conduction at fairly constant velocity A2H2 equal or slightly more than A1H1

11. A1H1 80 ms ~ A2H2 95 ms S1A1 ~ S2A2 ~ 55 ms H1V1 ~ H2V2 ~ 50 ms

12. S2 with short coupling interval Slowing of Conduction A1H1 < A2H2

13. A1H1 80 ms A2H2 140 ms

14. S2 with shorter coupling interval Blocked AES at AVN

15. Ventricular Extrastimulus testing Retrograde conduction over HPS and AVN Accessory pathway conduction Arrhythmia induction

16. Ventricular Extrastimulus testing Retrograde conduction over HPS and AVN Accessory pathway conduction Arrhythmia induction Stimulation at RV apex conventionally – RV apex Stim – distal RBB – HPS – AVN – RA

17. S2 with long coupling interval

18. H buried in V V1A1 almost equal to V2A2 Earliest atrial activation in HBE Atleast 30 ms before HRA Proximal-to-distal CS activation CONCENTRIC ATRIAL ACTIVATION

19. S2 with short coupling interval

20. S2 with shorter coupling interval

21. S2 with short coupling interval with short drive cycle length Blocked VES at AVN VA block Differs with – ES coupling interval – Drive cycle length

22. S2 with short coupling interval Tissue latency in local evoked response Occurs just above the tissue refractory period

23. Even shorter coupling interval Blocked VES locally at RV apex Loss of ventricular capture

24. Ventricular Extrastimulus testing Other ‘ Normal’ responses No VA conduction at all Atropine, Isoprenaline No VA conduction despite drugs

25. Ventricular Extrastimulus testing Other ‘ Normal’ responses No VA conduction at all Atropine, Isoprenaline No VA conduction despite drugs Retrograde exit site from AV node maybe near CS ostium rather than HBE – earliest atrial activation at Proximal CS

26. Ventricular Extrastimulus testing Other ‘ Normal’ responses No VA conduction at all Atropine, Isoprenaline No VA conduction despite drugs Retrograde exit site from AV node maybe near CS ostium rather than HBE – earliest atrial activation at Proximal CS Maneuvers to prove accessory pathway

27. Refractory periods

28. EFFECTIVE Refractory Period ERP of a tissue

29. EFFECTIVE Refractory Period ERP of a tissue (or a structure)

30. EFFECTIVE Refractory Period ERP of a tissue (or a structure) is the LONGEST coupling interval that fails to capture the tissue

31. EFFECTIVE Refractory Period ERP of a tissue (or a structure) is the LONGEST coupling interval that fails to capture the tissue (or be conducted over the structure)

32. FUNCTIONAL Refractory Period F RP of a tissue (or a structure) is the SHORTEST ‘output’ coupling interval that can be elicited from a tissue (or structure) by any ‘input’ interval

33. FUNCTIONAL Refractory Period F RP of a tissue (or a structure) is the SHORTEST ‘output’ coupling interval that can be elicited from a tissue (or structure) by any ‘input’ interval S1-A1-H1-V1 S2-A2-H2-V2 AVN HPS AV conduction system

34. RELATIVE Refractory Period R RP of a tissue (or a structure) is the ‘input’ interval at which the ‘output’ interval just begins to differ from ‘input’ interval

35. RELATIVE Refractory Period R RP of a tissue (or a structure) is the ‘input’ interval at which the ‘output’ interval just begins to differ from ‘input’ interval This is the point at which Latency or Decremental conduction begins to occur Least commonly measured

36. In all tissues, ERP and FRP are ‘length-dependent’ So, measured using atleast 2 different drive cycle lengths

37. AVN ERP Longest A1A2 interval that fails to capture HB A1A2 maybe longer than S1S2 due to tissue latency

38. AVN FRP Shortest H1H2 in response to any A1A2 interval

39. AVN RRP Longest A1A2 interval at which A2H2 exceeds A1H1

40. Normal range of refractory periods (ms) ERP Atria ERP AVN FRP AVN ERP HPS ERP V 150-350 230-430 330-530 330-450 190-290 * Denes , Akhtar , Durrer , Josephsen series

41. GAP phenomena ES conducted as LBBB

42. INCREMENTAL ATRIAL PACING

43. INCREMENTAL VENTRICULAR PACING

44. MINIMUM PROTOCOL Basic intervals SNRT and CSNRT AES – AVNERP AV WCL VES – VERP VA WCL

45. Arrhythmia induction

46. TO BE CONTINUED….

47. ….NEXT presentations Atrial arrhythmias Ventricular Pre-excitation and AVRT Ventricular arrhythmias Catheter ablation