Background:
A non-optimal resynchronization lead (RL) position is a possible cause of poor CRT response.
Objectives:
The study aims to test RT3DE value for individual assessment of LV dysynchrony and prospective evaluation of CRT response after RL implantation at the pre-determined SMMD whatever the method of CRT.
Methods:
Seventeen HF patients were prospectively included in the study. RT3DE data were obtained before and after 1, 3, 6 months of CRT. Time to minimal systolic volume (tmsv) was calculated from the 17 segment model obtaining systolic dyssynchrony index (SDI). Time/volume curves, parametric imaging were applied for pre-implant identification of SMMD and individual assessment of CRT response. Delta-time delay (delta-t) and selective parameters between tmsv of latest and earliest activated segments were calculated. All patients received CRT according to accessibility of SMMD. We used BFRVP in 5 patients with septal SMMD; BVP in 12 patients with LV SMMD.
Results:
The RL was successfully implanted at the SMMD or nearest segment in 14 (82.4%) initial responders (5 BFRVP, 9 BIVP). Twelve of them were responders after 6 months. CRT response was comparable in BFRVP and BIVP.
A moderate correlation between % change of EF and that of SDI (r=-.406), delta-t (-.497) was found. Baseline delta-t showed a stronger correlation with % change of EF(r=-.718**, P= 0.009) than that of SDI (r=-.509, P=0.091).
Conclusion:
The use of RT3DE for individual assessment of LV mechanical dysynchrony and for optimal RL positioning at the pre-identified SMMD can provide more optimum CRT regardless the method of CRT.