Gaibazzi Nicola, Petrucci Nicola, Ziacchi Vigilio
Department of Cardiology, Ospedale Civile, Desenzano del Garda (BS), Italy.
J Am Soc Echocardiogr. 2005 Dec;18(12):1270-6. doi: 10.1016/j.echo.2005.06.006.
The aims of this study were to investigate the clinical agreement between myocardial performance index (MPI) measured conventionally and by pulsed-wave tissue Doppler (PW-TD) of the mitral annulus, and to test whether PW-TD MPI can accurately differentiate between healthy subjects and patients affected by congestive heart failure (CHF) with mild to moderate reduction of systolic function.
Calculation of MPI using PW-TD may have advantages over conventional left ventricle inflow/outflow tract pulsed-wave Doppler (PWD) method; for example, all of the data needed for PW-TD MPI calculation can be derived from one single cardiac cycle, whereas with PWD at least two different cycles are needed. Thus, heart rate variability does not interfere with PW-TD MPI.
In group A, we included 70 healthy adults with normal left ventricular ejection fraction and normal diastole, whereas for group B we studied 50 patients with CHF and left ventricular ejection fraction between 35% and 45%. MPI measured with PWD was statistically different (P < .0001) from MPI measured with PW-TD both in group A (0.33 +/- 0.09 vs 0.42 +/- 0.09) and group B (0.69 +/- 0.15 vs 0.79 +/- 0.12). Nonetheless, clinical agreement existed between the two methods in the single subject. Receiver operating characteristic curves showed very high accuracy for both methods to discriminate patients with CHF from healthy subjects; the optimal cutoff point was different and specific to each method: 0.50 for the conventional method and 0.60 for the PW-TD method.
We found clinical agreement between MPI measured in the same subject with the conventional PWD method and with PW-TD. Both methods had similarly high diagnostic accuracy for CHF, but this study supports the use of a higher MPI cut-point for best diagnostic accuracy when using the new PW-TD method.
We performed a study in healthy adults and in patients with congestive heart failure to investigate the clinical agreement between MPI measured conventionally and by PW-TD of the mitral annulus. We found mild agreement between MPI measured by the conventional method and by PW-TD. Both methods had high diagnostic accuracy for CHF. PW-TD method requires a higher MPI cut-point for best diagnostic accuracy.
本研究旨在探讨传统测量的心肌性能指数（MPI）与二尖瓣环脉冲波组织多普勒（PW-TD）测量的MPI之间的临床一致性，并测试PW-TD MPI能否准确区分健康受试者和收缩功能轻度至中度降低的充血性心力衰竭（CHF）患者。
使用PW-TD计算MPI可能比传统的左心室流入/流出道脉冲波多普勒（PWD）方法具有优势；例如，PW-TD MPI计算所需的所有数据都可以从单个心动周期中得出，而使用PWD至少需要两个不同的周期。因此，心率变异性不会干扰PW-TD MPI。
A组纳入70名左心室射血分数正常且舒张功能正常的健康成年人，而B组研究50名CHF患者，其左心室射血分数在35%至45%之间。在A组（0.33±0.09对0.42±0.09）和B组（0.69±0.15对0.79±0.12）中，用PWD测量的MPI与用PW-TD测量的MPI在统计学上均有差异（P<0.0001）。尽管如此，两种方法在单个受试者中存在临床一致性。受试者工作特征曲线显示，两种方法在区分CHF患者和健康受试者方面都具有很高的准确性；最佳截断点不同且每种方法都有特异性：传统方法为0.50，PW-TD方法为0.60。
我们发现同一受试者用传统PWD方法和PW-TD测量的MPI之间存在临床一致性。两种方法对CHF的诊断准确性都同样高，但本研究支持在使用新的PW-TD方法时采用更高的MPI截断点以获得最佳诊断准确性。
我们对健康成年人和充血性心力衰竭患者进行了一项研究，以调查传统测量的MPI与二尖瓣环PW-TD测量的MPI之间的临床一致性。我们发现传统方法和PW-TD测量的MPI之间存在轻度一致性。两种方法对CHF都有很高的诊断准确性。PW-TD方法需要更高的MPI截断点以获得最佳诊断准确性。
