Firstenberg M S, Greenberg N L, Smedira N G, McCarthy P M, Garcia M J, Thomas J D
The Cleveland Clinic Foundation, Cleveland, USA.
Comput Cardiol. 2001;28:613-6.
Inertial forces (Mdv/dt) are a significant component of transmitral flow, but cannot be measured with Doppler echo. We validated a method of estimating Mdv/dt. Ten patients had a dual sensor transmitral (TM) catheter placed during cardiac surgery. Doppler and 2D echo was performed while acquiring LA and LV pressures. Mdv/dt was determined from the Bernoulli equation using Doppler velocities and TM gradients. Results were compared with numerical modeling. TM gradients (range: 1.04-14.24 mmHg) consisted of 74.0 +/- 11.0% inertial forcers (range: 0.6-12.9 mmHg). Multivariate analysis predicted Mdv/dt = -4.171(S/D (RATIO)) + 0.063(LAvolume-max) + 5. Using this equation, a strong relationship was obtained for the clinical dataset (y=0.98x - 0.045, r=0.90) and the results of numerical modeling (y=0.96x - 0.16, r=0.84). TM gradients are mainly inertial and, as validated by modeling, can be estimated with echocardiography.
惯性力（Mdv/dt）是二尖瓣血流的一个重要组成部分，但无法用多普勒超声心动图测量。我们验证了一种估计Mdv/dt的方法。10名患者在心脏手术期间放置了双传感器二尖瓣（TM）导管。在获取左心房（LA）和左心室（LV）压力的同时进行多普勒和二维超声心动图检查。使用多普勒速度和TM梯度通过伯努利方程确定Mdv/dt。将结果与数值模型进行比较。TM梯度（范围：1.04 - 14.24 mmHg）中74.0 +/- 11.0%为惯性力（范围：0.6 - 12.9 mmHg）。多变量分析预测Mdv/dt = -4.171（S/D（比率）） + 0.063（LA容积 - 最大值） + 5。使用该方程，临床数据集（y = 0.98x - 0.045，r = 0.90）和数值模型结果（y = 0.96x - 0.16，r = 0.84）之间获得了很强的相关性。TM梯度主要是惯性的，并且经模型验证，可以用超声心动图进行估计。
