Optimization of AV and VV Delays Lumax 540 CRM Training and Education Optimization of AV and VV Delays
Optimization of BiV Pacing A-V Delay V-V Delay
AV Delay Optimization Goals Ensure BiV pacing Improve diastolic filling Reduce mitral regurgitation Cardiac Output
AV Delay Optimization AV too long Close to intrinsic PR (fusion) Loss of CRT AV too short Premature mitral valve closure Hemodynamic compromise
AV Delay Optimization Methods Empirical Calculation Echocardiography Pulse pressure
AV Delay Optimization Aortic Pressure in percent LV dP/dtmax RV LV BiV Aortic Pressure in percent LV dP/dtmax in percent 16 24 12 18 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
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
AV Delay Optimization Limitations of Calculation Methods LV lead in anterior vein RBBB Intrinsic PR > 300 ms AV block II°/III°
AV Delay Optimization Doppler Echocardiography Flow Velocity at Mitral Valve Aortic Velocity Time Integral
Echocardiography 4 Chamber View Apical Position
Apical 4-Chamber View
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
Doppler-Echocardiography Blood flow velocity Spectral analysis 1.5 1.0 0.5
Mitral Valve Doppler Echo LV Ejection Filling ECG Doppler Sample Volume
Pulsed Wave Doppler Echo 4 Chamber View E/A Ratio Mitral Valve
Pulsed Wave Doppler Echo ECG E A Velocity (cm/s) Time (50mm/s)
AV Delay Optimization Doppler Echo Transmitral Flow Velocity LV filling pressure E wave Early diastolic passive filling of the left ventricle A wave Late diastolic active filling of the left ventricle atrial contribution
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
Left Bundle Branch Block R1 R2 R1 R2 P Q T T A A A A E
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
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
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
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
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)
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
AV Optimization Short AV Delay Long AV Delay Ritter Formula Forced MVC QA QA A wave truncation Spontaneous MVC A A E E Ritter Formula
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
Transmitral Flow At short AV delay AVshort = 50 ms QAshort = 128 ms Begin Q A E 128 ms
Transmitral Flow At long A-V delay AVlong = 160 ms QAlong = 48 ms Q A
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)-(128 - 48)] = 50 + (110 - 80) AVopt = 80 ms
AV Delay Optimization Short AV Long AV Optimal AV
AV Delay Optimization Doppler Echocardiography Flow Velocity at Mitral Valve Aortic Velocity Time Integral
Doppler Echo Apical Five Chamber View
Doppler Echo Aortic Flow Velocity Kruck, Biamino 1988
Aortic Flow Velocity LBBB A A A Aortic Flow Aortic Flow Time Velocity
Aortic Flow Velocity Biventricular Pacing AVD A E Aortic Flow Aortic Time Velocity
Velocity Time Integral Integral = Area under the curve VTI = AVO AVC V * dt (cm) Fehske 1988
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
AV Delay Optimization Velocity Time Integral VTI = 12.7 cm Dr. Uhrig, Vivantes Urban Hospital Berlin
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
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 10 - 15%
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
LV dP/dt max LV Pressure (mmHg) dP/dt (mmHg/s) Jansen et al., Am J Cardiol 2006
Compliance with LV dP/dt max. measurements Good Good to reasonable % Jansen et al., Am J Cardiol 2006
AV Delay Optimization Methods Empirical Calculation Echocardiography Pulse pressure
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
Pulse Pressure Method Intrinsic Paced Pressure P Vp Time Pressure P R Aorta LV PEP Time Auricchio et al., PACE 1998
Pulse Pressure Method BiV Pacing 110 Aortic Pressure (mmHg) 85 60 LV IEGM Time (s) 1 2 3 4 5 6 7 8 9
AV Delay Optimization Summary Pulse pressure: hemodynamic testing Calculation: initial programming Doppler Echo: non-responders
Optimization of BiV Pacing A-V Delay V-V Delay
V-V Delay Optimization AV AV AV AS AS AS VV VV LVP RVP LVP RVP RVP LVP VV = 0 LV first RV first
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
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
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
V-V Optimization 41 CHF pts. with CRT-PM No. of pts. 80 40 20 12 12 20 12 20 40 80 ms LV first RV first Bordachar et al., JACC 2004
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
V-V Optimization V-V Optimization van Gelder et al., Am J Cardiol 2004 AF SR ischemic SR non-ischemic V-V Optimization van Gelder et al., Am J Cardiol 2004
Optimizing BiV Pacing
Optimizing BiV Pacing RV only LV only BiV BiV LV first I V1
Optimizing V-V Delay Summary Start with standard setting VV optimization in patients with persistent dyssynchrony Trouble shooting option in clinical non-responders
Optimization of BiV Pacing A-V Delay V-V Delay