Grinstein Jonathan, Rodgers Daniel, Kalantari Sara, Sayer Gabriel, Kim Gene H, Sarswat Nitasha, Adatya Sirtaz, Ota Takeyoshi, Jeevanandam Valluvan, Burkhoff Daniel, Uriel Nir
ASAIO J. 2018 Jan/Feb;64(1):10-15. doi: 10.1097/MAT.0000000000000604.
Flow waveforms are an important feature of the HVAD left ventricular assist device (LVAD) that provides information about HVAD function and patient hemodynamics. We assessed the properties of one specific aspect of the waveform, the slope of the ventricular filling phase (VFP), and its correlation with pulmonary capillary wedge pressure (PCWP). A total of 101 screenshots from the HVAD monitor and simultaneous hemodynamic measurements were obtained simultaneously during sequential stages of invasive hemodynamic ramp studies. Each screenshot was digitized (IGOR Pro, WaveMetrics Inc., Oswego, OR) and properties of the flow waveforms including instantaneous flow and rate of change of flow were analyzed. Ventricular filling phase slope (VFPS) was calculated for each screenshot and correlated to PCWP. Ventricular filling phase slope was significantly higher in patients with PCWP ≥ 18 mm Hg than in patients with PCWP < 18 mm Hg [6.25 (5.84-7.37) L/min/s vs. 3.27 (2.00-4.69) L/min/s, p ≤ 0.0001]. A VFPS threshold of 5.8 L/min/s predicted a PCWP ≥ 18 mm Hg with a sensitivity of 87% and specificity of 95% (AUC 0.95). Ventricular filling phase slope of the HVAD flow waveform is a novel noninvasive parameter that correlates with PCWP and can discriminate elevated versus normal or low PCWP. Automated reporting of this parameter may help clinical assessment and management of patients supported by an HVAD and may serve as the basis of a smart LVAD pump that can adapt in response to changes in a patient's physiology.
血流波形是HeartWare心室辅助装置（HVAD）的一个重要特征，它能提供有关HVAD功能和患者血流动力学的信息。我们评估了波形一个特定方面的特性，即心室充盈期（VFP）的斜率，及其与肺毛细血管楔压（PCWP）的相关性。在有创血流动力学递增研究的连续阶段，同时获取了101张来自HVAD监测器的截图以及同步的血流动力学测量数据。每张截图都进行了数字化处理（IGOR Pro，WaveMetrics公司，俄勒冈州奥斯威戈），并分析了血流波形的特性，包括瞬时血流和血流变化率。计算了每张截图的心室充盈期斜率（VFPS），并将其与PCWP进行关联。PCWP≥18 mmHg的患者心室充盈期斜率显著高于PCWP<18 mmHg的患者[6.25（5.84 - 7.37）L/min/s对3.27（2.00 - 4.69）L/min/s，p≤0.0001]。VFPS阈值为5.8 L/min/s时，预测PCWP≥18 mmHg的敏感性为87%，特异性为95%（曲线下面积0.95）。HVAD血流波形的心室充盈期斜率是一个新的无创参数，与PCWP相关，能够区分PCWP升高与正常或降低的情况。自动报告该参数可能有助于对接受HVAD支持的患者进行临床评估和管理，并可能作为智能LVAD泵的基础，该泵能够根据患者生理变化进行自适应调整。
