Effective arterial elastance as an index of pulmonary vascular load
Effective arterial elastance as an index of pulmonary vascular load
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DOI：
10.1152/ajpheart.00796.2007
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发表时间：
2008-06-01
影响因子：
4.8
通讯作者：
D'Orio, Vincent
中科院分区：
文献类型：
--
作者：
Morimont, Philippe;Lambermont, Bernard;D'Orio, Vincent
本研究的目的是测试右心室（RV）收缩末期压（Pes）与每搏输出量（SV）的简单比值，即有效动脉弹性（E-a），是否可以有效评估肺栓塞或内毒素诱导的肺动脉高压的肺动脉负荷。同时记录两组6只纯Pietran猪的心室压力-容积（PV）数据（用电导导管获得）和有创肺动脉压力和流量波形，分别提交给肺栓塞（A组）或内毒素休克（B组）。A组在基线时和上级腔静脉注射自体血凝块（0.3 g/kg）后每30 min测量一次，B组在内毒素输注后每30 min测量一次。比较了两种肺动脉负荷的计算方法。一方面，采用肺动脉系统的三元件Windkessel模型（WK）计算E-a [E-a（WK）]，作为标准计算;另一方面，与体循环相似，E-a被评估为RV Pes与SV的比值[E-a（PV）= Pes/SV]。在两组中，尽管E-a（PV）和E-a（WK）之间的相关性在广泛的改变条件下非常好，但E-a（PV）系统性地高估了E-a（WK）。当左心房压力（Pla）并入E-a [E-a*（PV）=（Pes-Pla）/SV]时，该偏移消失。因此，E-a *（PV），定义为RV Pes减去Pla与SV的比值，提供了一种方便、有用和简单的方法来评估肺动脉负荷及其对RV功能的影响。
The aim of this study was to test whether the simple ratio of right ventricular (RV) end-systolic pressure (Pes) to stroke volume (SV), known as the effective arterial elastance (E-a), provides a valid assessment of pulmonary arterial load in case of pulmonary embolism-or endotoxin-induced pulmonary hypertension. Ventricular pressure-volume (PV) data (obtained with conductance catheters) and invasive pulmonary arterial pressure and flow waveforms were simultaneously recorded in two groups of six pure Pietran pigs, submitted either to pulmonary embolism (group A) or endotoxic shock (group B). Measurements were obtained at baseline and each 30 min after injection of autologous blood clots (0.3 g/kg) in the superior vena cava in group A and after endotoxin infusion in group B. Two methods of calculation of pulmonary arterial load were compared. On one hand, E-a provided by using three-element windkessel model (WK) of the pulmonary arterial system [E-a(WK)] was referred to as standard computation. On the other hand, similar to the systemic circulation, E-a was assessed as the ratio of RV Pes to SV [E-a(PV) = Pes/SV]. In both groups, although the correlation between E-a(PV) and E-a(WK) was excellent over a broad range of altered conditions, E-a(PV) systematically overestimated E-a(WK). This offset disappeared when left atrial pressure (Pla) was incorporated into E-a [E-a* (PV) = (Pes - Pla)/SV]. Thus E-a * (PV), defined as the ratio of RV Pes minus Pla to SV, provides a convenient, useful, and simple method to assess the pulmonary arterial load and its impact on the RV function.