Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota; Department of Surgery, University of Minnesota, Minneapolis, Minnesota; Medtronic, Mounds View, Minnesota.
Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota; Medtronic, Mounds View, Minnesota.
Heart Rhythm. 2019 Mar;16(3):443-450. doi: 10.1016/j.hrthm.2018.09.009. Epub 2018 Sep 18.
Permanent His-bundle pacing (HBP) is an attractive, perhaps more physiological, alternative to traditional right ventricular pacing.
The purpose of this study was to utilize direct visualization to more comprehensively understand the anatomy central to HBP, correlating electrical lead performance to implant locations along the His-bundle (HB) pathway.
Canine hearts (n = 5) were isolated and reanimated using Visible Heart methodologies. Medtronic 3830 SelectSecure leads were fixated where His potentials were present. The location of each implant was mapped/binned into 4 regions approximately analogous to the proximal, penetrating, and distal HB. Locational differences in HBP capture and resultant QRS morphology were assessed.
Average HBP capture thresholds did not significantly vary with respect to implant location (1.0-ms pulse width; P = .48). The resulting QRS morphologies from HB-paced beats varied in relation to implant location. As leads were placed further distally along the HB, the ratio of paced to native QRS complex duration increased (ΔQRS/ΔQRS ratios-region 2: 0.84 ± 0.16; region 3: 1.04 ± 0.42; region 4: 1.74 ± 0.86).
We demonstrated correlation between the anatomic locations of HBP lead placement and resultant QRS morphologies in a reanimated canine heart model. Proximal placement along the HB pathway resulted in more favorable QRS morphologies, suggesting improved selective HBP capture, with no significant increase in HBP capture thresholds. Pacing the HB in more proximal pathway locations improved the selectivity of HBP and may confer electrical and anatomic benefits relative to distal HBP.
永久性希氏束起搏（HBP）是一种有吸引力的替代传统右心室起搏的方法，可能更具生理性。
本研究旨在利用直接可视化来更全面地了解与希氏束（HB）途径相关的解剖结构的中心，将电导线性能与 HB 途径中的植入位置相关联。
使用可见心脏方法分离和再激活犬心（n = 5）。将 Medtronic 3830 SelectSecure 导联固定在存在希氏电位的位置。每个植入物的位置都被映射/分类到 4 个区域，大致类似于 HB 的近端、穿透和远端。评估了 HB 捕获和由此产生的 QRS 形态的位置差异。
平均 HBP 捕获阈值与植入位置无关（1.0ms 脉冲宽度；P =.48）。来自 HB 起搏节拍的 QRS 形态因植入位置而异。随着导联沿着 HB 进一步放置在远端，起搏与固有 QRS 复合持续时间的比值增加（ΔQRS/ΔQRS 比值-区域 2：0.84 ± 0.16；区域 3：1.04 ± 0.42；区域 4：1.74 ± 0.86）。
我们在一个再激活的犬心模型中证明了 HBP 导联放置的解剖位置与由此产生的 QRS 形态之间的相关性。HB 途径近端的放置导致更有利的 QRS 形态，这表明选择性 HBP 捕获得到改善，而 HBP 捕获阈值没有显著增加。在 HB 的更近端途径位置起搏 HB 可以提高 HBP 的选择性，并可能相对于 HB 远端提供电生理和解剖优势。
