use of echocardiography to optimize cardiac ... · v-v interval optimization • exclude anodal...
TRANSCRIPT
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Use of Echocardiography to Optimize Cardiac
Resynchronization Therapy
Kevin M. Mulhern, M.D.Director, Echocardiography Laboratory
The University of Kansas Hospital
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Echo & CRT• Before implantation
– Patient selection– Optimal site for LV pacing
• After implantation– Assess response to therapy– Optimize device function
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Requirements
• Appropriate• Feasible• Reproducible• Practical
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Appropriate Use Criteria
• Initial evaluation or re-evaluation after revascularization and/or optimal medical therapy to determine candidacy for device therapy and/or to determine optimal choice of device (Appropriate)
• Initial evaluation for CRT device optimization after implantation (Uncertain)
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Appropriate Use Criteria
• Symptoms possibly due to device complication or suboptimal device settings (Appropriate)
• Routine surveillance of implanted device without change in clinical status or cardiac examination (Inappropriate)
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46 y/o woman with dilated cardiomyopathyhas NYHA class III heart failure despiteoptimal medical therapy. LVEF=25% andQRS duration=150 ms. What would yourecommend?a. Biventricular pacemaker-defibrillatorb. CRT-D if septal-posterior wall motion
delay ≥130 msc. CRT-D if interventricular mechanical delay
≥40 msd. CRT-D if Yu index ≥32 mse. Cardiac MRI to determine presence or
absence of myocardial fibrosis
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PROSPECT• 53 centers in Europe, Hong Kong & USA• 498 patients with standard CRT indications• 12 echo parameters of dyssynchrony• Clinical composite score response
– Sensitivity=6% to 74%– Specificity=35% to 91%
• LVESV response– Sensitivity=9% to 77%– Specificity=31% to 91%
• Wide variability in analysis
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Mayo Clinic Study• Single center study• Less variability in analysis• 131 patients with standard CRT indications• 14 echo parameters of dyssynchrony• Predicted reverse remodeling (≥15% ESV)
– Nonischemic: None– Ischemic: M-mode SPWMD, TD strain & isovolumic
time, but only modest incremental value
• Predicted clinical response (>10% improvement in MLHFQ, 6MWD, or VO2max)– None
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Can we do better?
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Longitudinal Dyssynchrony Analysis Using TDI
Significant dyssynchrony present if difference in time to peak systolic velocity ≥60 ms
From Gorcsan III J, Tanabe M, Bleeker B et al. Combined longitudinal and radial dyssynchrony predicts ventricular response after resynchronization therapy. J Am Coll Cardiol 2007;50:1476-1483.
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Strain (ϵ)• Describes deformation (e.g., fractional
change in length of myocardial segment)• Unitless and usually expressed as
percentage• Positive strain (lengthening)• Negative strain (shortening)• Longitudinal, circumferential, and radial
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Radial Dyssynchrony Analysis Using 2-D Speckle Tracking Strain
Significant dyssynchrony present if difference in time to peak strain ≥130 ms
From Gorcsan III J, Tanabe M, Bleeker B et al. Combined longitudinal and radial dyssynchrony predicts ventricular response after resynchronization therapy. J Am Coll Cardiol 2007;50:1476-1483.
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Response to CRT
Longitudinal Radial Both
Sensitivity 72% 84% 88%
Specificity 77% 73% 80%
From Gorcsan III J, Tanabe M, Bleeker B et al. Combined longitudinal and radial dyssynchrony predicts ventricular response after resynchronization therapy. J Am Coll Cardiol 2007;50:1476-1483.
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Response to CRT
From Gorcsan III J, Tanabe M, Bleeker B et al. Combined longitudinal and radial dyssynchrony predicts ventricular response after resynchronization therapy. J Am Coll Cardiol 2007;50:1476-1483.
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TARGET
From Khan F, Virdee M, Palmer C et al. Targeted left ventricular lead placement to guide cardiac resynchronization therapy—the TARGET study: a randomized, controlled trial. J Am Coll Cardiol 2012;59:1509-1518.
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TARGET
From Khan F, Virdee M, Palmer C et al. Targeted left ventricular lead placement to guide cardiac resynchronization therapy—the TARGET study: a randomized, controlled trial. J Am Coll Cardiol 2012;59:1509-1518.
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Change After CRT
Target*(n=103)
Control*(n=104) p value
NYHA Class -1.1 ± 0.7 -0.8 ± 0.7 0.0026MWD (m) 61 ± 76 38 ± 76 0.011
MLHFQ -22 ± 20 -16 ± 19 0.024LVEDV (ml) -41 ± 34 -23 ± 23 0.001LVESV (ml) -46 ± 33 -26 ± 23 0.001LVEF (%) 8 ± 7 5 ± 8 0.001
*Mean ± SD
Adapted from Khan F, Virdee M, Palmer C et al. Targeted left ventricular lead placement to guide cardiac resynchronization therapy—the TARGET study: a randomized, controlled trial. J Am Coll Cardiol 2012;59:1509-1518.
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TARGET
From Khan F, Virdee M, Palmer C et al. Targeted left ventricular lead placement to guide cardiac resynchronization therapy—the TARGET study: a randomized, controlled trial. J Am Coll Cardiol 2012;59:1509-1518.
• Concordant—At optimal site• Adjacent—Within one segment• Remote—At least 2 segments away
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58 y/o man with ischemic heart disease hasNYHA class III heart failure, an EF=30%, andQRS duration=110 ms. Medications areaspirin 81 mg daily, carvedilol 25 mg b.i.d.,lisinopril 20 mg daily, spironolactone 25 mgdaily, and furosemide 40 mg daily. Whatwould you recommend?a. Biventricular pacemaker-defibrillatorb. CRT-D if septal-posterior wall motion delay
≥130 msc. CRT-D if interventricular mechanical delay
≥40 msd. CRT-D if speckle tracking radial
dyssynchrony ≥130 mse. Evaluate for heart transplantation
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Borderline QRS Duration• Single center study• 221 consecutive patients
– 135 with QRS >130 ms (168 ± 26 ms)– 86 with QRS 100-130 ms (115 ± 8 ms)
• 6 echo parameters of dyssynchrony• Response
– ≥15% increase in EF and– ≥10% decrease in ESV
• 201 with baseline echo data• 187 with follow-up data after 8 ± 5 months
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Ejection Fraction Response to CRT
From Oyenuga O, Hara H, Tanaka H et al. Usefulness of echocardiographic dyssynchrony in patients with borderline QRS duration to assist with selection for cardiac resynchronization therapy. J Am Coll Cardiol Img 2010;3:132-140.
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Ejection Fraction Response to CRT
From Oyenuga O, Hara H, Tanaka H et al. Usefulness of echocardiographic dyssynchrony in patients with borderline QRS duration to assist with selection for cardiac resynchronization therapy. J Am Coll Cardiol Img 2010;3:132-140.
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Reverse Remodeling After CRT
From Oyenuga O, Hara H, Tanaka H et al. Usefulness of echocardiographic dyssynchrony in patients with borderline QRS duration to assist with selection for cardiac resynchronization therapy. J Am Coll Cardiol Img 2010;3:132-140.
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76 y/o man with ischemic heart diseaseunderwent implantation of CRT-P sixmonths ago. His condition improvedinitially, but he has developed increasingdyspnea on exertion during the past month.What would you recommend?a. Increase lower rate limit of CRT
pacemaker to increase cardiac outputb. Perform echo-guided device optimizationc. Reposition RV lead on septumd. Reposition LV lead in another veine. Evaluate for heart transplantation
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A-V Delay Optimization:Maximizing LV Filling
• Goals– Enhance atrial contribution to
ventricular filling– Program shortest A-V delay without
truncating active phase of LV filling– Ensure ventricular contraction
begins immediately after active phase of LV filling
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A-V Delay Optimization
• Inappropriate– Atrial fibrillation– Frequent PVCs– Tachycardia– Mitral valve prosthesis
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A-V Delay Optimization
• Evaluate device function first• Temporarily disable
– Rate response– Mode switching– Rate adaptive A-V delay
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CRT Optimization:Simplified Screening
• Step 1: Optimize ECG signal• Step 2: Optimize pulsed Doppler
mitral inflow velocity using– High sweep speeds– Low filters– Sample volume set at mitral annulus
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CRT Optimization:Simplified Screening
• Step 3: Examine mitral inflow pattern at level of annulus. A-V optimization protocol may not be required if– E and A waves are clearly identified and
separated, and– Termination of A wave occurs at least 40
milliseconds before QRS onset or mitral valve closure click, and
– E wave less than A wave
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A-V Delay Optimization• Begin with long A-V delay
– Fusion of E and A waves or– Loss of biventricular pacing
• Decrease A-V delay in 20 ms increments until– Loss of A wave or– A-V delay=60 ms
• Within this range of A-V delay settings, find– Optimal LV inflow pattern and– Largest stroke volume
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Absent or Truncated A Wave:A-V Delay Too Short
From Gorcsan III J, Abraham T, Agler DA et al. Echocardiography for cardiac resynchronization therapy: recommendations for performance and reporting. A report from the American Society of Echocardiography Dyssynchrony Writing Group. Endorsed by the Heart Rhythm Society. J Am Soc Echocardiogr 2008;21:191-231.
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E & A Waves Fused:A-V Delay Too Long
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Diastolic Mitral Regurgitation:A-V Delay Too Long
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Optimal E & A Waves
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Optimal Stroke Volume
• Velocity-Time Integral (VTI)• Assuming constant LVOT diameter,
stroke volume is directly proportional to LVOT VTI
• Use VTI as surrogate for stroke volume
• Change >10% is significant
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LVOT Velocity-Time Integral
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V-V Interval Optimization:Restoring Ventricular Synchrony
& Maximizing Stroke Volume
• Goals– Increase ejection fraction– Reduce mitral regurgitation
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V-V Interval Optimization
• Inappropriate– Frequent PVCs– Tachycardia– Ejection fraction ≥50%
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V-V Optimization
• Program A-V delay before V-V timing• Optimal V-V interval usually LV
before RV by 20-40 ms• V-V interval >40 ms uncommon• Simultaneous biventricular pacing
(V-V interval=0) may be best for some patients
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LVOT VTI Method
• Use VTI as surrogate for stroke volume
• Change >10% is significant• Keep RA-LV timing constant
while varying V-V timing– Changes in RA-LV timing will
change LV filling time, VTI, and stroke volume
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A-V Delay During V-V Programming
Problem: Sensed A-V delay is different than optimized A-V delay when RV is paced before LV.Solution: Pace the atrium above the intrinsic rate.
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V-V Interval Optimization• Exclude anodal stimulation during LV only
pacing prior to V-V programming– Only applies if pacing polarity is LV tip to RV
coil or RV ring• Measure LVOT VTI
– LV before RV by 0 ms, 10 ms, 20 ms, 40 ms, 60 ms & 80 ms then
– RV before LV by 10 ms, 20 ms, 40 ms, 60 ms & 80 ms
• Determine optimal V-V interval based on highest LVOT VTI
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Tips: CRT Optimization• Annotate settings on echo image• Use LVOT VTI and LV inflow pattern
obtained with pulsed Doppler• Sample velocity parallel to flow to ensure
measurement of maximum velocity• Display with lower velocity scales to
reduce error of measurements• Use 100 mm/s sweep speed• Breathing suspended at end expiration• Acquire, measure, and average 3 beats• Wait 1 minute between programming
changes before measuring