Evaluation of the Fetal Left Ventricular Myocardial Performance Index (MPI) by Using an Automated Measurement of Doppler Signals in Normal Pregnancies

Abstract

The myocardial performance index is widely used as an indicator of the heart’s performance. However, due to the subjective nature of ultrasonic testing, there are differences in the measurements among inspectors, requiring a quantitative and objective assessment. In this study, an automated program was developed to quantitatively evaluate the myocardial performance index (MPI) and the cardiac time intervals in the left ventricle for each trimester. One hundred and thirty-three pregnant women who visited the hospital for prenatal examinations were studied, and skilled inspectors obtained left ventricular blood flow waveforms from 47 fetuses in the 12 weeks, 54 fetuses in the 22 weeks, and 32 fetuses in the 31 weeks of pregnancy using a pulse Doppler mode of ultrasound equipment. The acquired images automatically measured the isovolumetric contraction time (IVCT), isovolumetric relaxation time (IVRT,) ejection time (ET), and filling time (FT), and calculated the Tei index (TI) and the K-index (KI); each interval was manually measured during the actual inspection for comparison. In this study, the ultrasonic Doppler waveform was objectively analyzed and measured by the automated program, and it will help with the evaluation of fetal heart function.

Turkish reference ranges for the left fetal modified myocardial performance index

“…With the introduction of routine use in automated methods, the relationship of MPI with fetal pathologies will be understood more clearly in the future. 31,32 Previous studies have reported that a learning process is required in order to perform accurate MPI measurements. For example, Cruz-Martinez et al 30 reported average numbers related to the completion of the learning process associated with left Mod-MPI measurements, such as 42 for ET, 77 for ICT, and 83 for IRT.…”

Myocardial performance index and cardiovascular diseases

“…23 Hashemi et al Cases (24-40 weeks) with idiopathic mildly increased AFI Idiopathically, a slight rise in the amniotic fluid index (AFI) was linked to a big rise in the fetal MPI in both the left and right ventricles Ref. 24 Kim et al…”

“…22 Idiopathically, a slight rise in the amniotic fluid index (AFI) was linked to a big rise in the fetal MPI in both the left and right ventricles. 23 Kim et al 24 made an automated way to recognize IVCT, IVRT, and ET and figure out the MPI so that the LV MPI of fetuses can be measured quantitatively and objectively with ultrasonic doppler. All tasks except data collection were done automatically, and the actual measurements of the same fetus were used to figure out the clinical value.…”

How Automated Techniques Ease Functional Assessment of the Fetal Heart: Applicability of MPI+™ for Direct Quantification of the Modified Myocardial Performance Index

“…As a non-invasive, pulsed-wave (PW) Doppler-derived measure of global myocardial function, it is currently used to evaluate fetal cardiac anatomy, hemodynamics and function [1]. By now, the Mod-MPI has been widely used to assess the function of the heart in a wide variety of pathological intrauterine conditions by estimating early fetal cardiac adaptive changes in complicated pregnancies, including fetal growth restriction (FGR), gestational diabetes, twin-to-twin transfusion syndrome (TTTS), congenital heart defects (CHD), pre-eclampsia, intrahepatic cholestasis of pregnancy (ICP) and other fetal intra-and extracardiac conditions [1,3,[17][18][19][20][21][22]. Ventricular dysfunction is associated with higher MPI values.…”