Variation in optimal hemodynamic atrio-ventricular delay of biventricular pacing with different endocardial left ventricular lead locations using precision hemodynamics

IntroductionIt is not known whether the optimal atrioventricular (AV(opt)) delay varies between left ventricular (LV) pacing site during endocardial biventricular pacing (BiVP) and may therefore needs consideration. MethodsWe assessed the hemodynamic AV(opt) in patients with chronic heart failure undergoing endocardial LV lead implantation. AV(opt) was assessed during atrio-BiVP with a "roving LV lead." Up to four locations were studied: mid-lateral wall, mid-septum (or a close alternative), site of greatest hemodynamic improvement, and LV lead implant site. The AV(opt) was compared to a fixed AV delay of 180 ms. ResultsSeventeen patients were included (12 male, aged 66.5 +/- 12.8 years, ejection fraction 26 +/- 7%, 16 left bundle branch block or high percentage of right ventricular pacing [RVP], QRS duration 167 +/- 27 ms). In most locations (62/63), AV(opt) increased systolic blood pressure during BiVP compared with RVP (relative improvement 6 mmHg, interquartile range [IQR] 4-9 mmHg). Compared to a fixed AV delay, the hemodynamic improvement at AV(opt) was higher (1 mmHg, IQR 0.2-2.6 mmHg, p < .001). Within most patients (16/17), we observed a difference in AV(opt) between pacing sites (median paced AV(opt) 209 ms, IQR 117-250). Within this range, the hemodynamic impact of these differences was small (median loss 0.6 mmHg, IQR 0.1-2.6 mmHg). ConclusionWithin a patient, different endocardial LV lead locations have slightly different hemodynamic AV(opt) which are superior to a fixed AV delay. The hemodynamic consequence of applying an optimum from a different lead location is small.