BACKGROUND: Whether sequential biventricular pacing provides substantial benefits over conventional simultaneous stimulation remains unclear, particularly regarding the differences between ischemic and non-ischemic patients. The purpose of this study was to evaluate the acute effect of interventricular pacing interval (V-V) optimization on left ventricular (LV) systolic performance and dyssynchrony in ischemic versus non-ischemic patients. METHODS: Sixty-nine consecutive patients underwent cardiac resynchronization therapy. Within 3 days after implantation, V-V was optimized by measuring (every 20-millisecond interval) LV systolic performance (LV outflow-tract velocity-time-integral, LVOT VTI) and LV dyssynchrony (using tissue Doppler imaging). Optimal pacing configuration was the one achieving maximal increase in LVOT VTI. RESULTS: Optimized sequential pacing provided a significant improvement in LVOT VTI compared to simultaneous stimulation (from 138 +/- 42 to 163 +/- 38 mm, P < .001) and was associated with a significant reduction in LV dyssynchrony (from 33 +/- 31 to 19 +/- 24 milliseconds, P < .001). The increase in LVOT VTI and LV ejection fraction after implantation was greater in non-ischemic as compared to ischemic patients (P < .001). However, V-V optimization yielded a larger improvement in LV systolic performance in ischemic patients (P = .03). Consequently, the 2 groups showed comparable response after V-V optimization. A significant correlation was observed between LV scar tissue and optimal V-V interval (r = 0.58, P < .001), with a larger extent of scar related to a larger level of LV preactivation, probably reflecting slow intra-LV conduction. CONCLUSIONS: Optimized sequential biventricular pacing further increased LV systolic performance as compared to simultaneous stimulation, particularly in ischemic patients where the presence of a large scar was correlated with a larger LV preactivation.
BACKGROUND: Whether sequential biventricular pacing provides substantial benefits over conventional simultaneous stimulation remains unclear, particularly regarding the differences between ischemic and non-ischemicpatients. The purpose of this study was to evaluate the acute effect of interventricular pacing interval (V-V) optimization on left ventricular (LV) systolic performance and dyssynchrony in ischemic versus non-ischemicpatients. METHODS: Sixty-nine consecutive patients underwent cardiac resynchronization therapy. Within 3 days after implantation, V-V was optimized by measuring (every 20-millisecond interval) LV systolic performance (LV outflow-tract velocity-time-integral, LVOT VTI) and LV dyssynchrony (using tissue Doppler imaging). Optimal pacing configuration was the one achieving maximal increase in LVOT VTI. RESULTS: Optimized sequential pacing provided a significant improvement in LVOT VTI compared to simultaneous stimulation (from 138 +/- 42 to 163 +/- 38 mm, P < .001) and was associated with a significant reduction in LV dyssynchrony (from 33 +/- 31 to 19 +/- 24 milliseconds, P < .001). The increase in LVOT VTI and LV ejection fraction after implantation was greater in non-ischemic as compared to ischemicpatients (P < .001). However, V-V optimization yielded a larger improvement in LV systolic performance in ischemicpatients (P = .03). Consequently, the 2 groups showed comparable response after V-V optimization. A significant correlation was observed between LV scar tissue and optimal V-V interval (r = 0.58, P < .001), with a larger extent of scar related to a larger level of LV preactivation, probably reflecting slow intra-LV conduction. CONCLUSIONS: Optimized sequential biventricular pacing further increased LV systolic performance as compared to simultaneous stimulation, particularly in ischemicpatients where the presence of a large scar was correlated with a larger LV preactivation.
Authors: Khalin F Dendy; Brian D Powell; Yong-Mei Cha; Raul E Espinosa; Paul A Friedman; Robert F Rea; David L Hayes; Margaret M Redfield; Samuel J Asirvatham Journal: Indian Pacing Electrophysiol J Date: 2011-05-01
Authors: Benjamin J Rubinstein; Daniel Y Wang; Santos E Cabreriza; Bin Cheng; Linda Aponte-Patel; Alexandra Murata; Alexander Rusanov; Marc E Richmond; T Alexander Quinn; Henry M Spotnitz Journal: J Thorac Cardiovasc Surg Date: 2012-08-21 Impact factor: 5.209
Authors: Heather J Kagan; Varujan D Belekdanian; Jiqiu Chen; Peter Backeris; Nadjib Hammoudi; Irene C Turnbull; Kevin D Costa; Roger J Hajjar Journal: J Appl Physiol (1985) Date: 2017-10-19