Each pacing phase was long enough to reach stable interventricular conduction times. Pacing voltage in the test was set to double value of pacing threshold. Pacing rate was then increased by 10 BPM steps up to 140 BPM or reaching the Wenckebach point. Initial pacing rate was equal to intrinsic heart rate rounded up to the closest ten. To assess interventricular conduction during natural ventricular activation the atrial lead was paced incrementally.
Pacing was started at heart rate equivalent to the closest upper ten of the intrinsic heart rate and then increased in 10 BPM steps up to 140 BPM. To assess the influence of pacing rate on interventricular conduction time duration an incremental pacing test was performed.Pacing rate was set to 90 BPM to avoid intrinsic activation. Lowest pacing voltage was rounded to the closest upper whole number value over recently measured pacing threshold, then increased with 1 V steps up to 10 V. To rule out voltage dependency of interventricular conduction times an incremental voltage test was performed.To assess dependency of particular pacing rings location to interventricular conduction time all above mentioned vectors were tested.
Measurement protocol was divided into four parts: Thus, using a quadrupolar electrode it was possible to create 6 unique vectors compared to only two when using a bipolar electrode. The following LV quadrupolar lead couples were paced consecutively: proximal & middle proximal, middle proximal & middle distal and middle distal & distal ring. Then LV lead was paced and conduction to RV lead measured. In case of using quadripolar LV lead it meant to pace RV and to measure conduction times in LV lead-bipolarly coupled proximal & middle proximal, middle proximal & middle distal and middle distal & rings consecutively.
Pacing vectors between RV and LV leads were tested and conduction times measured. Conduction times were measured automatically using “Conduction times” tool integrated into the ICS 3000 Pacing System Module application. The funders had no role in study design, data collection, and analysis, decision to publish, or preparation of the manuscript.Ĭompeting interests: The authors have declared that no competing interests exist.Īll measurements were done using Biotronik ICS 3000 Operation / Implant module (Biotronik GmbH & Co.KG Berlin Germany). įunding: This work was supported by the Ministry of Health, Czech Republic - conceptual development of research organization (FNBr, 65269705) and MUNI/A/1446/2019. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: The data underlying this study are available from the Harvard Dataverse using the following URL. Received: NovemAccepted: JanuPublished: February 19, 2020Ĭopyright: © 2020 Novotny et al. PLoS ONE 15(2):Įditor: Giuseppe Coppola, University Hospital *Paolo Giaccone*, ITALY (2020) Differences in right-to-left vs left-to-right interventricular conduction times in patients indicated to cardiac resynchronization therapy. Citation: Pospisil D, Novotny T, Jarkovsky J, Farkasova B, Kozak M, Krivan L, et al.