Rick Schreurs

50 Chapter 3 25% 50% 75% 100% AV-delay (% of Intrinsic AV-delay -30ms) -40 -20 0 20 40 60 * * * * BiV Pacing RV Pacing 25% 50% 75% 100% AV-delay (% of Intrinsic AV-delay -30ms) -40 -20 20 40 60 80 * * * * 220 240 260 280 300 320 340 LV Volume (m) 0 20 40 60 80 100 120 220 240 260 280 300 320 340 LV Volume (mL) 0 20 40 60 80 100 120 Baseline (AAI) 75% 50% 25% Biventricular pacing Right ventricular pacing A LV pressure (mmHg) LV pressure (mmHg) Δ Stroke volume (%) Δ Stroke work (%) B C Δ Stroke volume (%) compared to baseline (AAI) Δ Stroke work (%) compared to baseline (AAI) 0 Patient data Figure 6. Hemodynamic effect of improving atrioventricular (AV)-coupling in patients during biven- tricular (BiV) and right ventricular (RV) pacing. (A) Left ventricular (LV) pressure-volume loops in a representative patient at baseline (dashed line) and at tested AV-delay settings (solid lines) during BiV pacing ( Left ) and RV pacing ( Right ). Relative changes in stroke volume ( B ) and stroke work ( C ) as compared to baseline (AAI) for BiV (black) and RV pacing (orange) in the entire cohort. Mean±SD are presented. * indicates p<0.05 as compared to baseline.