Hemodynamic comparison of different multisites and multipoint pacing strategies in cardiac resynchronization therapies

PurposeIn order to increase the responder rate to CRT, stimulation of the left ventricular (LV) from multiple sites has been suggested as a promising alternative to standard biventricular pacing (BIV). The aim of the study was to compare, in a group of candidates for CRT, the effects of different pacing configurationsBIV, triple ventricular (TRIV) by means of two LV leads, multipoint (MPP), and multipoint plus a second LV lead (MPP + TRIV) pacingon both hemodynamics and QRS duration.MethodsFifteen patients (13 male) with permanent AF (mean age 767years; left ventricular ejection fraction 337%; 7 with ischemic cardiomyopathy; mean QRS duration 178 +/- 25ms) were selected as candidates for CRT. Two LV leads were positioned in two different branches of the coronary sinus. Acute hemodynamic response was evaluated by means of a RADI pressure wire as the variation in LVdp/dtmax.Resultsp id="Par3"Per patient, 2.7 +/- 0.7 veins and 5.2 +/- 1.9 pacing sites were evaluated. From baseline values of 998 +/- 186mmHg/s, BIV, TRIV, MPP, and MPP-TRIV pacing increased LVdp/dtmax to 1200 +/- 281mmHg/s, 1226 +/- 284mmHg/s, 1274 +/- 303mmHg, and 1289 +/- 298mmHg, respectively (p<0.001). Bonferroni post-hoc analysis showed significantly higher values during all pacing configurations in comparison with the baseline; moreover, higher values were recorded during MPP and MPP + TRIV than at the baseline or during BIV and also during MPP + TRIV than during TRIV. Mean QRS width decreased from 178 +/- 25ms at the baseline to 171 +/- 21, 167 +/- 20, 168 +/- 20, and 164 +/- 15ms, during BIV, TRIV, MPP, and MPP-TRIV, respectively (p<0.001).Conclusionsp id="Par4"In patients with AF, the acute response to CRT improves as the size of the early activated LV region increases