Letter by Tedford et al Regarding Article, "Effective Arterial Elastance in the Pulmonary Arterial Circulation: Derivation, Assumptions, and Clinical Applications".
Letter by Tedford et al Regarding Article, "Effective Arterial Elastance in the Pulmonary Arterial Circulation: Derivation, Assumptions, and Clinical Applications".
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Tedford 等人关于文章“肺动脉循环中的有效动脉弹性：推导、假设和临床应用”的信函。
DOI：
10.1161/circheartfailure.120.007081
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Kass,DavidA
中科院分区：
文献类型：
--
作者：
Tedford,RyanJ;Hsu,Steven;Kass,DavidA
我们饶有兴趣地阅读了 Brener 等人撰写的深思熟虑的文章，其中指出了计算肺有效动脉弹性 (Ea)（右心室 (RV) 后负荷的集总参数）时的几个关键考虑因素。当我们考虑如何最好地评估健康和疾病中的 RV-肺动脉 (PA) 耦合时，这些问题至关重要。作者指出，正常的右心室压力-容积环形状在射血早期达到峰值，收缩末期压力下降，这与隔膜上的对应情况完全不同。因此，射血末容量低于 RV 收缩末期容量，并且通过平均肺动脉压 (mPAP) 而不是收缩期峰值压 (sPAP) 可以更好地估计收缩末压 (Pes)。最后，他们指出，由于左心房压力通常更接近 mPAP，因此在计算 Ea 时不应忽略它。我们同意，对于正常的肺血管负荷，这些警告可能适用。然而，即使出现轻度肺动脉高压 (PH)，右心室的 PV 环形状也会随着射血过程中压力的升高而变化，并在收缩末期或接近收缩末期达到峰值，与左心室非常相似（图）。随着形态上的这种变化，射血末期和收缩末期发生的体积几乎相同，并且正如我们和其他人所证明的那样，sPAP 比 mPAP 更能近似 Pes。 2, 3 我们进一步注意到，在没有左心房压力升高的情况下，肺血管回路的平均阻力 × 顺应性（RC，或舒张压舒张时间常数）的乘积相当恒定 4，使得 mPAP 和 sPAP 高度线性相关。对于全身动脉系统来说情况就不那么严重了。因此，我们认为 sPAP 在 PH 情况下作为 Pes 的估计优于 mPAP。
We read with interest the thoughtful piece by Brener et al1 which points out several key considerations when calculating pulmonary effective arterial elastance (Ea), a lumped parameter of right ventricular (RV) afterload. These issues are critical as we consider how best to assess RV-pulmonary arterial (PA) coupling in health and disease. The authors note that the normal RV pressure-volume loop shape peaks early in ejection with declining pressures to end-systole quite unlike its counterpart across the septum. Thus, end-ejection volume is lower than the volume at RV end-systole, and end-systolic pressure (Pes) is better estimated by mean pulmonary artery pressure (mPAP) rather peak systolic pressure (sPAP). Lastly, they note that as left atrial pressure is often much closer to mPAP, it should not be ignored when calculating Ea. We agree that for normal pulmonary vascular loads these caveats likely apply. Upon development of even mild pulmonary hypertension (PH), however, PV-loop shape for the RV changes with pressure rising throughout ejection and peaking at or near end-systole, much as for the LV (Figure). With this change in morphology, end-ejection and end-systole occur at near-identical volumes, and Pes is better approximated by sPAP than mPAP as we and others have shown. 2, 3 We further note that the product of mean resistance× compliance for the pulmonary vascular circuit (RC, or time constant of diastolic pressure relaxation), is fairly constant 4 in the absence of elevated left atrial pressure, making mPAP, and sPAP highly linearly correlated. This is less so for the systemic arterial system. Therefore, we believe that sPAP is superior to mPAP as an estimate of Pes in the setting of PH.
DOI：
10.1152/ajpheart.00796.2007
发表时间：
2008-06-01
影响因子：
4.8
作者：
Morimont, Philippe;Lambermont, Bernard;D'Orio, Vincent
通讯作者：
D'Orio, Vincent
清醒狗肺循环对急慢性肺静脉高压的脉动血流动力学反应分析
影响因子：
20.1
作者：
R. Hopkins;J. Hammon;P. A. McHale;P. K. Smith;R. Anderson
通讯作者：
R. Anderson