Fusion‐Optimized Intervals (FOI): A New Method to Achieve the Narrowest QRS for Optimization of the AV and VV Intervals in Patients Undergoing Cardiac Resynchronization Therapy

Abstract

The FOI method is feasible, further reduces QRS duration, and improves acute hemodynamic response compared to nominal programming of CRT.

The concept of triple wavefront fusion during biventricular pacing: Using the EGM to produce the best acute hemodynamic improvement in CRT

“…They found that optimal ventricular resynchronization was reached when BiVp fused with intrinsic conduction. These findings confirm similar observations in other studies …”

“…These findings confirm similar observations in other studies. 12,13,29 In our study, triple wavefront fusion was present during the settings associated with the best hemodynamic improvement by CRT in the vast majority of patients. The optimal moment for RVp in our cohort was around the onset of the intrinsic farfield signal (at 98 ± 17%% of RA-RV farfield ) while preactivating the LV at 50% of the RA-RV sense interval.…”

Impact of Pacing Site on QRS Duration and Its Relationship to Hemodynamic Response in Cardiac Resynchronization Therapy for Congestive Heart Failure

“…Several studies have confirmed this assumption and reported that decrease in QRSd during CRT was a predictor of acute and chronic hemodynamic responses to CRT. Moreover, adjusting the RV, LV pacing site, or AV delay individually to reduce QRSd was also associated with an improvement in the impact of CRT . However, contradictory results have also been published.…”

“…Moreover, adjusting the RV, LV pacing site, or AV delay individually to reduce QRSd was also associated with an improvement in the impact of CRT. 16,[18][19][20][21] However, contradictory results have also been published. Recently, Gold et al have analyzed the changes in QRSd during BiV pacing in the REVERSE trial involving 610 patients.…”

Left Ventricular Lead Placement Targeted at the Latest Activated Site Guided by Electrophysiological Mapping in Coronary Sinus Branches Improves Response to Cardiac Resynchronization Therapy

“…Additionally, although QRS intervals were similar at baseline, MG had a significantly shorter QRS interval than controls at the 6-month follow-up, which is comparable with better cardiac synchrony in MG. A longer Q-LV interval and a shorter QRS interval have been reported to be a better prognostic parameter of CRT response. [16][17][18][19][20] Thus, the Q-LV interval in MG versus CG represents a better prognosis of the former in this study. In the SMART-AV study, Gold et al found that patients with a Q-LV greater than the median 95 milliseconds had better outcomes.…”