0. Optimization of AV and VV Delays
CRT Program CRM Training and Education
Optimization of AV and VV Delays

1. Follow-up of CRT Patients
Physical Examination
Device Control
Chest x-ray
CPX or Walking
Doppler- Echo
Discharge
1 mon
3 mon
6 mon
12 mon
Every Year    – –  – 

2. Optimization of BiV Pacing
A-V Delay
V-V Delay

3. AV Delay Optimization Goals Ensure BiV pacing
Improve diastolic filling
Reduce mitral regurgitation
Cardiac Output 

4. AV Delay Optimization AV too long Close to intrinsic PR (fusion)
Loss of CRT
AV too short
Premature mitral valve closure
Hemodynamic compromise

5. AV Delay Optimization Methods Pulse pressure Empirical Calculation
Echocardiography

6. AV Delay Optimization Methods Pulse pressure Empirical Calculation
Echocardiography

7. Pulse Pressure Method Objective
Identify AV delay that provides maximal difference between systolic and diastolic blood pressure
Procedure
Arterial line to measure central aortic pressure accurately

8. Pulse Pressure Method Intrinsic BiV Paced Pressure P Vp Time Pressure
Aorta LV
PEP
Time
Auricchio et al., PACE 1998

9. Pulse Pressure Method BiV Pacing 110 Aortic Pressure (mmHg) 85 60
LV IEGM
Time (s) 1 2 3 4 5 6 7 8 9

10. AV Delay Optimization Methods Pulse pressure Empirical Calculation
Echocardiography

11. AV Delay Optimization Measurements
Intrinsic AV (As-Vs) from IEGM recording
Intrinsic QRS width from 12-lead ECG

12. AV Delay Optimization Empiric Calculation
Wide QRS (> 150 ms) AVopt (ms) = 0.70 * As-Vs - 55
Narrow QRS ≤ 150 ms AVopt (ms) = 0.70 * As-Vs

13. AV Delay Optimization Examples
QRS = 170 ms; As-Vs = 220 ms AVopt (ms) = 0.70 * = 99 ms
QRS = 130 ms; As-Vs = 180 ms AVopt (ms) = 0.70 * 180 = 126 ms

14. AV Delay Optimization Aortic Pressure LV dP/dtmax BiV LV RV 16 24 1218 8 12 4 6 PR
- 30 ms PR
- 30 ms -4 -6
-12 -8
A-V Delay
A-V Delay
Auricchio et al., Circulation 1999

15. AV Delay Optimization Calculation (PR interval) - 30 ms AVopt = 2
Example for As-Vs = 220 ms AVopt = (220-30)/2 = 95 ms
Auricchio et al., Circulation 1999

16. Limitations of Calculation Methods
AV Delay Optimization
Limitations of Calculation Methods
LV lead in anterior vein
RBBB
Intrinsic PR > 300 ms
AV block II°/III°

17. AV Delay Optimization Methods Pulse pressure Empirical Calculation
Echocardiography

18. AV Delay Optimization Doppler Echocardiography
Flow Velocity at Mitral Valve
Aortic Velocity Time Integral

19. Echocardiography
4 Chamber View
Apical Position

20. Apical 4-Chamber View

21. Apical 4-Chamber View
Normal

22. Apical 4-Chamber View
Normal with CS

23. Doppler-Echocardiography
Fd = Doppler frequency
f0 = Ultrasound frequency (e.g., 2.4 MHz)
V = Blood flow velocity
 = Angle between sound beam and direction of blood flow
c = Speed of sound in human tissue (1,530 m/s)
2 V cos 
Fd = f0 c

24. Doppler-Echocardiography
Blood flow velocity
Spectral analysis
1.5
1.0
0.5

25. Mitral Valve Doppler Echo
LV Ejection
Filling
ECG
Doppler
Sample
Volume

26. Pulsed Wave Doppler Echo
4 Chamber View
E/A Ratio
Mitral Valve

27. Pulsed Wave Doppler Echo
ECG E A
Flow
Velocity
(cm/s)
50 mm/s

28. AV Delay Optimization Doppler Echo
Transmitral Flow Velocity  LV filling pressure
E wave Early diastolic passive filling
A wave Late diastolic active filling  atrial contribution

29. Normal Heart Cycle R P T P P Q S A A A E IVC IVR E IVC IVR E Aortic
Flow
Aortic
Flow
Isovolumic
Contraction
Isovolumic
Relaxation
LVFT
Left Ventricular
Filling Time

30. Left Bundle Branch Block
R1 R2
R1 R2 P Q T T A A A A E

31. LBBB: Late MV Closure R1 R2 R1 R2 P Q T P P Mitral Valve Closure MVC A
IVC*
IVC*
Aortic Valve Opening
AVO
* IVC = Isovolumic Contraction

32. LBBB: Late End of LV Systole
R1 R2
R1 R2 P Q T P P
MVC
MVC A A A
IVC
IVC
Aortic
Flow
Aortic
Flow
AVO
Aortic Valve Closure
Ejection
LV Systole

33. LBBB: Late Start of LV Filling
R1 R2
R1 R2 P Q T P Q T P
MVC
MVO* A A A
IVC
IVR*
Aortic
Flow
Aortic
Flow
AVO
AVC
* MVO = Mitral Valve Opening
** IVR = Isovolumic Relaxation

34. LBBB: Fusion of E and A R1 R2 R1 R2 P Q T P Q T P A A A E E E Aortic
Flow
Aortic
Flow
Short LV
Filling
Time
250 ms
at HR 65/min

35. LBBB: Resynchronization
R1 R2
R1 R2 P Q T P Q T P
MVC A A A E
IVC
IVR E E
Aortic
Flow
Aortic
Flow
Pre Ejection Period (PEP)

36. Biventricular Pacing BiV BiV BiV AVD T T P P P MVC MVC A A A E IVC E
Aortic
Flow
Aortic
Flow
Pro- longed
LV Filling
Time
PEP
325 ms
at HR 65/min

37. AV Optimization Short AV Delay Long AV Delay “Ritter Formula” Forced
MVC AV AV P P QA QA
A wave
truncation
Spontaneous
MVC A A E E
“Ritter Formula”

38. AVopt = AVshort + [(AVlong - AVshort) - (QAshort - QAlong)]
AV Delay Optimization
Ritter Formula
"The Difference of the Differences"
AVopt = AVshort + [(AVlong - AVshort) - (QAshort - QAlong)]
Programmed AV Delays
AVshort = short AV (25% of PR)
AVlong = long AV (75% of PR)
Measured QA Intervals
QAshort = QA at short AV
QAlong = QA at long AV
Ritter et al., PACE 1995

39. Transmitral Flow At short AV delay AVshort = 50 ms QAshort = 128 ms
Begin Q A E
128 ms

40. Transmitral Flow At long A-V delay AVlong = 160 ms QAlong = 48 ms Q A

41. AV Delay Optimization Result Programmed AV Delays AVshort = 50 ms
AVlong = 160 ms
Measured QA Intervals
QAshort = 128 ms
QAlong = 48 ms
"The Difference of the Differences"
AVopt = AVshort + [(AVlong - AVshort) - (QAshort - QAlong)]
AVopt = 50 + [(160-50)-( )]
= 50 + ( )
AVopt = 80 ms

42. AV Delay Optimization
Short AV
Long AV
Optimal AV

43. AV Delay Optimization
Saxon et al., NASPE 2004

44. AV Delay Optimization
Long AV 160 ms
Short AV 50 ms
Optimal AV 100 ms

45. AV Delay Optimization Doppler Echocardiography
Flow Velocity at Mitral Valve
Aortic Velocity Time Integral

46. Doppler Echo
Apical Five Chamber View

47. Doppler Echo
Aortic Flow Velocity
Kruck, Biamino 1988

48. Aortic Flow Velocity
LBBB A A A
Aortic
Flow
Aortic
Flow
Time
Velocity

49. Aortic Flow Velocity Biventricular Pacing AVD A E Aortic Flow Aortic
Time
Velocity

50. Velocity Time Integral
Integral = Area under the curve
VTI =
AVO
AVC
V * dt
(cm)
Fehske 1988

51. Velocity Time Integral
Ejection time
Time
vmax
vmean
Vmax = 1.58 m/s
Vmean = 1.09 m/s
ET = 288 ms
VTI = Vmean * ET
VTI = 0.31 m
Velocity
(m/s)
ECG

52. AV Delay Optimization Velocity Time Integral VTI = 12.7 cm
Dr. Uhrig, Vivantes Urban Hospital Berlin

53. VTI Method Derived Parameters Stroke Volume SV = VTI * A
VTI = Velocity Time Integral
A = Aortic Valve Area
Cardiac Output
CO = SV * HR
HR = Heart Rate
Fehske 1988

54. VTI Method Objective Identify optimal AV delay at max. VTI Procedure
CW Doppler of aortic outflow tract
Decrement AV delay by 20 ms down to ≥ 80 ms
Limitations
Doppler signal quality
Breathing modulations
Intrinsic error %

55. AV Delay Optimization
30 Pts. after CRT implantation NYHA III-IV, LVEF < 35%, SR
BiV on atrial sensed beats AV optimization on LV dp/dt max
Comparison to Ritter formula, diastolic filling time (DFT), LV VTI, E/A VTI
Jansen et al., Am J Cardiol 2006

56. LV dP/dt max LV Pressure (mmHg) dP/dt (mmHg/s)
Jansen et al., Am J Cardiol 2006

57. Agreement with LV dP/dt max
Good
Good to reasonable %
Jansen et al., Am J Cardiol 2006

58. AV Delay Optimization Methods Empirical Calculation Echocardiography
Pulse pressure

59. AV Delay Optimization Summary Pulse pressure: hemodynamic testing
Calculation: initial programming
Doppler Echo: non-responders

60. Optimization of BiV Pacing
A-V Delay
V-V Delay

61. V-V Delay OptimizationAV AV AV AS AS AS VV VV
LVP
RVP
LVP
RVP
RVP
LVP
VV = 0
LV first
RV first

62. V-V Optimization 41 pts. with CHF after CRT-PM AV delay optimization
RV-/LV pre-activation: 0, 12, 20, 40, 80 ms
Endpoints: Cardiac output, mitral regurgitation from echo
Bordachar et al., JACC 2004

63. V-V Optimization Echocardiographic Parameters
M-mode: septal-to-posterior wall motion delay (SPWMD)
Doppler: Interventricular mechenical delay (IVMD)
Tissue Doppler:
Intra LV delay onset (LV onset)
Intra LV delay peak (LV peak)
SD from 12 segments intra LV delay peak (SD LV peak))
Delayed longitudinal contraction (DLC)
Bordachar et al., JACC 2004

64. V-V Optimization Correlation to Hemodynamics Cardiac Output
Mitral Regurgitation
Parameter
LV peak
SD LV peak
LV onset
DLC
SPWMD
IVMD
-0.67
-0.64
-0.48
-0.41
-0.24
0.68
0.63
0.51
0.24
0.06
Bordachar et al., JACC 2004

65. V-V Optimization Tissue Doppler Imaging – Intra LV delay peak
Cardiac Output
Mitral Regurgitation
Bordachar et al., JACC 2004

66. V-V Optimization 41 CHF pts. with CRT-PM No. of pts. 80 40 20 12 12 2012 20 40 80 ms
LV first
RV first
Bordachar et al., JACC 2004

67. V-V Optimization 166 DCM pts. with CRT (Doppler Echo) No. of pts. 80
At Implant
3 months
No. of pts. 80 40 20 20 40 80 ms
LV first
RV first
Delurgio et al., NASPE 2002

68. V-V Optimization van Gelder et al., Am J Cardiol 2004 AF SR ischemic
SR non-ischemic
van Gelder et al., Am J Cardiol 2004

69. V-V Optimization 32 HF pts. with CRT, 20 CAD, SR, QRS 170 ms, EF 23%
dP/dtmax
Baseline
VV=0
QuickOpt
VVdP/dt
van Gelder et al., JCE 2008

70. Optimizing BiV Pacing

71. Optimizing BiV Pacing
RV only
LV only
BiV
BiV LV first I V1

72. Optimizing V-V Delay Summary Start with standard setting
VV optimization in patients with persistent dyssynchrony
Trouble shooting option in clinical non-responders

73. Optimization of BiV Pacing
A-V Delay
V-V Delay