School of Sport & Health Sciences, Cardiff Metropolitan University, Cardiff, UK; Department of Medicine, Division of Cardiology, Columbia University Irving Medical Center, New York, New York.
Department of Medicine, Division of Cardiology, Columbia University Irving Medical Center, New York, New York.
J Heart Lung Transplant. 2023 Sep;42(9):1223-1232. doi: 10.1016/j.healun.2023.04.002. Epub 2023 Apr 23.
Reduced arterial pulsatility in continuous-flow left ventricular assist devices (CF-LVAD) patients has been implicated in clinical complications. Consequently, recent improvements in clinical outcomes have been attributed to the "artificial pulse" technology inherent to the HeartMate3 (HM3) LVAD. However, the effect of the "artificial pulse" on arterial flow, transmission of pulsatility into the microcirculation and its association with LVAD pump parameters is not known.
The local flow oscillation (pulsatility index, PI) of common carotid arteries (CCAs), middle cerebral arteries (MCAs) and central retinal arteries (CRAs-representing the microcirculation) were quantified by 2D-aligned, angle-corrected Doppler ultrasound in 148 participants: healthy controls, n = 32; heart failure (HF), n = 43; HeartMate II (HMII), n = 32; HM3, n = 41.
In HM3 patients, 2D-Doppler PI in beats with "artificial pulse" and beats with "continuous-flow" was similar to that of HMII patients across the macro- and microcirculation. Additionally, peak systolic velocity did not differ between HM3 and HMII patients. Transmission of PI into the microcirculation was higher in both HM3 (during the beats with "artificial pulse") and in HMII patients compared with HF patients. LVAD pump speed was inversely associated with microvascular PI in HMII and HM3 (HMII, r = 0.51, p < 0.0001; HM3 "continuous-flow," r = 0.32, p = 0.0009; HM3 "artificial pulse," r = 0.23, p = 0.007), while LVAD pump PI was only associated with microcirculatory PI in HMII patients.
The "artificial pulse" of the HM3 is detectable in the macro- and microcirculation but without creating a significant alteration in PI compared with HMII patients. Increased transmission of pulsatility and the association between pump speed and PI in the microcirculation indicate that the future clinical care of HM3 patients may involve individualized pump settings according to the microcirculatory PI in specific end-organs.
在连续血流左心室辅助装置（CF-LVAD）患者中，动脉搏动性降低与临床并发症有关。因此，最近临床结果的改善归因于 HeartMate3（HM3）LVAD 固有的“人工脉冲”技术。然而，“人工脉冲”对动脉血流、脉动向微循环的传递及其与 LVAD 泵参数的关系尚不清楚。
通过二维对准、角度校正的多普勒超声，在 148 名参与者中量化颈总动脉（CCA）、大脑中动脉（MCA）和中央视网膜动脉（代表微循环）的局部血流振荡（脉动指数，PI）：健康对照组，n=32；心力衰竭（HF），n=43；HeartMate II（HMII），n=32；HM3，n=41。
在 HM3 患者中，在具有“人工脉冲”和“连续流”的搏动中，2D-Doppler PI 与 HMII 患者在宏观和微观循环中相似。此外，HM3 患者与 HMII 患者的收缩期峰值速度无差异。与 HF 患者相比，HM3（在具有“人工脉冲”的搏动期间）和 HMII 患者的 PI 向微循环的传递更高。在 HMII 和 HM3 中，LVAD 泵速与微血管 PI 呈负相关（HMII，r=0.51，p<0.0001；HM3“连续流”，r=0.32，p=0.0009；HM3“人工脉冲”，r=0.23，p=0.007），而 LVAD 泵 PI 仅与 HMII 患者的微循环 PI 相关。
HM3 的“人工脉冲”在宏观和微观循环中均可检测到，但与 HMII 患者相比，PI 无明显变化。脉动传递增加以及微循环中泵速与 PI 的关系表明，HM3 患者未来的临床护理可能涉及根据特定终末器官的微循环 PI 进行个体化的泵设置。
