Department of Cardiology, Asklepieion General Hospital, Athens, Greece.
Hellenic J Cardiol. 2011 Jan-Feb;52(1):23-9.
The ratio of early diastolic transmitral velocity to early mitral annular diastolic velocity (E/Ea) can be used to group patients according to filling pressures. However this relationship has not been validated in the intermediate group (E/Ea = 8-15). The time difference between the onset of E and Ea also correlates with left ventricular (LV) filling pressures. The purpose of our study was to evaluate the correlation between the time interval difference of isovolumic relaxation (T[IVRT-IVRTa]) and N-terminal pro-brain natriuretic peptide (NTpro-BNP) in patients with an intermediate E/Ea ratio.
Echocardiography was performed simultaneously with NTpro-BNP measurement in 60 consecutive patients who had an intermediate E/Ea and were in sinus rhythm. Ea and the isovolumic relaxation time (IVRTa) at the septal and lateral sites of the mitral annulus were measured using pulsed tissue Doppler and the average was utilised. Pulsed Doppler was used to measure E and IVRT. E/Ea and IVRT-IVRTa (T[IVRT-IVRTa]) were calculated.
We demonstrated significant correlations between T[IVRT-IVRTa] and NTpro-BNP (r = -0.72, p<0.001), maximal systolic velocity of the mitral annulus (Sa: r = -0.50, p < 0.001), pulmonary artery systolic pressure (r = 0.42, p = 0.002), IVRTa (r = -0.27, p = 0.03), LV ejection fraction (LVEF: r = -0.26, p = 0.04), IVRT (r = -0.24, p = 0.04). We were unable to demonstrate significant relationships between NTpro-BNP and E deceleration time, left atrial diameter/area/volume, Ea or E. By a multiple linear regression analysis, including T[IVRT-IVRTa], IVRT, IVRTa, E/Ea, LVEF, pulmonary artery systolic pressure and Sa as potential determinants, TIVRT-IVRTa (= -0.57, p < 0.001) was shown to be the best independent predictor of NTpro-BNP (r 2 = 0.68, p < 0.001).
T[IVRT-IVRTa] correlates strongly with NTpro-BNP levels in patients with intermediate E/Ea, and could be used as a simple echocardiographic index, with reasonable accuracy.
早期舒张期二尖瓣血流速度与二尖瓣环早期舒张速度之比（E/Ea）可用于根据充盈压对患者进行分组。然而，这种关系在中间组（E/Ea=8-15）中尚未得到验证。等容舒张时间（IVRT）起始与 Ea 起始之间的时间差也与左心室（LV）充盈压相关。本研究的目的是评估中间 E/Ea 比值患者的等容舒张期（T[IVRT-IVRTa]）时间差与 N 末端脑利钠肽前体（NTpro-BNP）之间的相关性。
对 60 例连续窦性心律且 E/Ea 处于中间范围的患者同时进行超声心动图和 NTpro-BNP 测量。使用脉冲组织多普勒测量二尖瓣环间隔和侧壁的 Ea 和等容松弛时间（IVRTa），并取平均值。使用脉冲多普勒测量 E 和 IVRT。计算 E/Ea 和 IVRT-IVRTa（T[IVRT-IVRTa]）。
我们发现 T[IVRT-IVRTa]与 NTpro-BNP（r=-0.72，p<0.001）、二尖瓣环最大收缩速度（Sa：r=-0.50，p<0.001）、肺动脉收缩压（r=0.42，p=0.002）、IVRTa（r=-0.27，p=0.03）、左心室射血分数（LVEF：r=-0.26，p=0.04）、IVRT（r=-0.24，p=0.04）之间存在显著相关性。我们未能证明 NTpro-BNP 与 E 减速时间、左心房直径/面积/容积、Ea 或 E 之间存在显著关系。通过多元线性回归分析，包括 T[IVRT-IVRTa]、IVRT、IVRTa、E/Ea、LVEF、肺动脉收缩压和 Sa 作为潜在决定因素，T[IVRT-IVRTa]（=-0.57，p<0.001）是 NTpro-BNP 的最佳独立预测因子（r2=0.68，p<0.001）。
在 E/Ea 处于中间范围的患者中，T[IVRT-IVRTa]与 NTpro-BNP 水平密切相关，可用作一种简单的超声心动图指数，具有合理的准确性。
