通过二尖瓣血流和肺静脉血流相结合的方法对左心房最大dp/dt进行无创评估。

Noninvasive assessment of left atrial maximum dP/dt by a combination of transmitral and pulmonary venous flow.

作者信息

Nakatani S, Garcia M J, Firstenberg M S, Rodriguez L, Grimm R A, Greenberg N L, McCarthy P M, Vandervoort P M, Thomas J D

机构信息

Cardiovascular Imaging Center and the Department of Cardiology, The Cleveland Clinic Foundation, Ohio 44195, USA.

出版信息

J Am Coll Cardiol. 1999 Sep;34(3):795-801. doi: 10.1016/s0735-1097(99)00263-6.

DOI:10.1016/s0735-1097(99)00263-6

PMID:10483962

Abstract

OBJECTIVES

The study assessed whether hemodynamic parameters of left atrial (LA) systolic function could be estimated noninvasively using Doppler echocardiography.

BACKGROUND

Left atrial systolic function is an important aspect of cardiac function. Doppler echocardiography can measure changes in LA volume, but has not been shown to relate to hemodynamic parameters such as the maximal value of the first derivative of the pressure (LA dP/dt(max)).

METHODS

Eighteen patients in sinus rhythm were studied immediately before and after open heart surgery using simultaneous LA pressure measurements and intraoperative transesophageal echocardiography. Left atrial pressure was measured with a micromanometer catheter, and LA dP/dt(max) during atrial contraction was obtained. Transmitral and pulmonary venous flow were recorded by pulsed Doppler echocardiography. Peak velocity, and mean acceleration and deceleration, and the time-velocity integral of each flow during atrial contraction was measured. The initial eight patients served as the study group to derive a multilinear regression equation to estimate LA dP/dt(max) from Doppler parameters, and the latter 10 patients served as the test group to validate the equation. A previously validated numeric model was used to confirm these results.

RESULTS

In the study group, LA dP/dt(max) showed a linear relation with LA pressure before atrial contraction (r = 0.80, p < 0.005), confirming the presence of the Frank-Starling mechanism in the LA. Among transmitral flow parameters, mean acceleration showed the strongest correlation with LA dP/dt(max) (r = 0.78, p < 0.001). Among pulmonary venous flow parameters, no single parameter was sufficient to estimate LA dP/dt(max) with an r2 > 0.30. By stepwise and multiple linear regression analysis, LA dP/dt(max) was best described as follows: LA dP/dt(max) = 0.1 M-AC +/- 1.8 P-V - 4.1; r = 0.88, p < 0.0001, where M-AC is the mean acceleration of transmitral flow and P-V is the peak velocity of pulmonary venous flow during atrial contraction. This equation was tested in the latter 10 patients of the test group. Predicted and measured LA dP/dt(max) correlated well (r = 0.90, p < 0.0001). Numerical simulation verified that this relationship held across a wide range of atrial elastance, ventricular relaxation and systolic function, with LA dP/dt(max) predicted by the above equation with r = 0.94.

CONCLUSIONS

A combination of transmitral and pulmonary venous flow parameters can provide a hemodynamic assessment of LA systolic function.

摘要

目的

本研究评估了是否可以使用多普勒超声心动图无创估计左心房（LA）收缩功能的血流动力学参数。

背景

左心房收缩功能是心脏功能的一个重要方面。多普勒超声心动图可以测量左心房容积的变化，但尚未显示与诸如压力一阶导数的最大值（LA dP/dt(max)）等血流动力学参数相关。

方法

对18例窦性心律患者在心脏直视手术前后立即进行研究，同时测量左心房压力并进行术中经食管超声心动图检查。使用微测压导管测量左心房压力，并获得心房收缩期间的LA dP/dt(max)。通过脉冲多普勒超声心动图记录二尖瓣和肺静脉血流。测量心房收缩期间每个血流的峰值速度、平均加速度和减速度以及时间-速度积分。最初的8例患者作为研究组，以推导从多普勒参数估计LA dP/dt(max)的多元线性回归方程，后10例患者作为测试组以验证该方程。使用先前验证的数值模型来证实这些结果。

结果

在研究组中，LA dP/dt(max)与心房收缩前的左心房压力呈线性关系（r = 0.80，p < 0.005），证实了左心房中Frank-Starling机制的存在。在二尖瓣血流参数中，平均加速度与LA dP/dt(max)的相关性最强（r = 0.78，p < 0.001）。在肺静脉血流参数中，没有单个参数足以以r2>0.30估计LA dP/dt(max)。通过逐步和多元线性回归分析，LA dP/dt(max)的最佳描述如下：LA dP/dt(max)=0.1 M-AC±1.8 P-V - 4.1；r = 0.88，p < 0.0001，其中M-AC是二尖瓣血流的平均加速度，P-V是心房收缩期间肺静脉血流的峰值速度。该方程在测试组的后10例患者中进行了测试。预测的和测量的LA dP/dt(max)相关性良好（r = 0.90，p < 0.0001）。数值模拟验证了这种关系在广泛的心房弹性、心室舒张和收缩功能范围内成立，上述方程预测的LA dP/dt(max)的r = 0.94。