Cardiovascular Implantable Electronic Devices -> Tachycardia Devices: -> Device Technology D-PO06 - Poster Session VI (ID 26) Poster

D-PO06-037 - A New Algorithm, Auto Av Delay Setting Fused With Own Intrinsic Conduction In Multipoint Pacing, Is More Beneficial For Acute Hemodynamics (ID 652)


Background: Cardiac resynchronization therapy (CRT) has provided significant benefits to heart failure patients. But one-third of the patients received conventional CRT (c-CRT) have failed to respond. Although initial experience has shown that Multipoint pacing (MPP) provides acute hemodynamic benefit and improved outcome compared with c-CRT. Recently, various new algorithms are available, automatically adjust AV delay according to intrinsic AV conduction (fused AV delay), including SyncAV (fixed fusion AV delay) and Adaptive CRT (Auto adapt fused AV delay).
Objective: The objective of this study was to evaluate the acute hemodynamic effect of fused AV delay in MPP and the relationship between QRS duration and acute hemodynamics changes.
Methods: The Left ventricular (LV) dP/dtmax was measured with a pressure wire advanced in the LV. Ratio dp/dtmax (R-dp/dt), which was defined as change ratio of dp/dtmax compared with baseline, was examined in various pacing parameters. Short AV delay was defined as 120 ms. SyncAV and Adaptive CRT were employed as fused AV delay. AV delay in SyncAV was defined as 50 ms preceded from intrinsic AV delay. Main pacing configuration of Adaptive CRT was LV only pacing, and SyncAV was biventricular pacing (BiV). Ratio QRS (R-QRS) was defined as change ratio of QRS duration compared with baseline. The interaction between R-dp/dt and R-QRS duration was also examined.
Results: In thirty-eight patients, mean age was 67.5±9.3 years old, mean LV ejection fraction was 29.7±7.6%, and mean QRS duration was 144.6±21.7 ms. R-dP/dt was significantly greater in MPP than that in c-CRT (10.5% vs 8.4%, p= 0.009), and in fused AV delay than that in short AV delay (11.8% vs 9.1%, p=0.009) on MPP. R-dp/dt was negatively correlated with R-QRS duration in total pacing configuration. R-QRS in Adaptive CRT was significantly less than in SyncAV (1.5% vs 15.1 p<0.001). However, R-dp/dt was significantly greater in Adaptive CRT than in SyncAV (14.4% vs 11.8%, p=0.035).
Conclusion: More acute hemodynamic improvement was obtained in MPP compared with c-CRT, and in short AV delay than fusion AV delay, and in Adaptive CRT than SyncAV. Although R-QRS could be a predictor of hemodynamic improvement, it may not apply when compare LV only pacing and BiV pacing.