1. L. Wu, MD; C.P. Allaart, MD, PhD; G.J. de Roest, MD; M.L. Hendriks, MA; A.C. van Rossum, MD, PhD; C.C. de Cock MD, PhD ACC Scientific Sessions, San Francisco, CA 9 March 2013 The influence of right ventricular pacing on response to biventricular stimulation -An acute pressure-volume loop study-

2. Cardiac resynchronization therapy Standard therapy in end-stage heart failure LV only versus biventricular pacing Leclercq et al. JACC 2002Thibault et al., Circ 2011Kass et al., Circ 1999 p=0.001

3. Cardiac resynchronization therapy Contribution RV only pacing? –Detrimental effects on LV –In LBBB patients –Higher degree of mechanical dyssynchrony –Decrease in contractility Thambo et al., Circ 2004Sweeney et al., JACC 2006Auricchio et al., JACC 2002Tops et al., JACC 2009

4. Aim To investigate the influence of RV pacing on hemodynamic response during biventricular stimulation

5. Methods Patients eligible for CRT –Temporary pacing leads –Conductance measurements RA lead RV lead PL lead Conductance catheter

6. Pressure-volume loop Baseline RV only LV only Biventricular

7. Results Baseline characteristicsn=59 Age (yrs)67±10 Male39 (66%) QRS (ms)154±21 Ischaemic, n36 (61%) NYHA, n I / II / III / IV0 / 14 / 45 / 0 NT-pro BNP (ng/L)1637±1375 LVEDV (ml)294±151 LVESV (ml)232±142 LVEF (%)22±13

8. Acute effect of pacing on SW p=NS p<0.001 p=NS

9. Acute effect of pacing on dP/dt max p<0.001 p=NS p=0.002 p=NS

10. Correlation RV only and Biv response LV only gives a larger SW improvement than Biv Biv gives a larger SW improvement than LV only ∆ SW Biv - ∆ SW LV only (%)

11. Clinical consequences Response > 20% SW increase de Roest et al., Eur J HF 2012 Responders 68%

12. Non-responders SW improvement < 20% 52% better SW response 34% responders BivLV only

13. Conclusion Acute SW change during CRT is significantly modulated by RV pacing The amount of modulation is similar to the SW response during RV pacing Addition of RV pacing to LV pacing may positively or negatively affect outcome In CRT non-responders, the effect of switching off RV pacing should be evaluated individually

14. Acknowledgement VU University Medical Center Amsterdam –C.P. Allaart, MD, PhD –G.J. de Roest, MD –M.T. Rijnierse, MD –M.L. Hendriks, MA –A.C. van Rossum, MD, PhD –C.C. de Cock, MD, PhD Thank you!

15. SW response to Biv pacing Responders (n=30)Non-responders (n=29)p-value Age (yrs)67±1167±100.96 Male14 (47%)25 (86%)<0.01 QRS (ms)154±17154±250.94 Ischemic, n17 (57%)19 (66%)0.49 NYHA, n I / II / III / IV0 / 6 / 20 / 10 / 8 / 21 / 0 0.54 NT-pro BNP (ng/L)1440±15691891±10590.27 LVEDV (ml)225±89335±1880.04 LVESV (ml)187±62279±1820.02 LVEF (%)26±919±150.03 15

16. SW response to LV pacing 16 Responders (n=40)Non-responders (n=19)p-value Age (yrs)67±1168±90.83 Male25 (63%)14 (74%)0.40 QRS (ms)155±20152±240.71 Ischemic, n22 (55%)14 (74%)0.17 NYHA, n I / II / III / IV0 / 29 / 1 / 00 / 4 / 15 / 0 0.73 NT-pro BNP (ng/L)1649±14691610±11640.93 LVEDV (ml)267±92351±2230.04 LVESV (ml)202±77297±2120.01 LVEF (%)25±1017±170.03

17. Non-response Reverse response > 20% SW decrease 17 Reverse responders 21%

18. Correlation dP/dt max 18 ∆ SW Biv - ∆ SW LV only (%) LV only gives a larger SW improvement than Biv Biv gives a larger SW improvement than LV only ∆SW RV (%)