Aditi Mahajan

The (Pulsed-Wave) Doppler Fetal Myocardial Performance Index: Technical Challenges, Clinical Applications and Future Research.

Functional cardiovascular assessment is becoming an increasingly important tool in the study of fetal pathology. The myocardial performance index (MPI) is a parameter measuring global myocardial function. Since its introduction, several studies have proposed methods to improve its reproducibility and have constructed normative reference ranges. Fetal heart evaluation using the MPI is technically challenging, requiring specific training and expertise, and a consensus has yet to be reached on the method of delineating the time periods used to calculate the index. Despite these limitations, it has been shown to be a useful and highly sensitive parameter of dysfunction in a number of fetal pathologies. Further research is warranted into the effect of pathology on MPI, parameters of unilateral cardiac strain that utilise MPI, and automation of the MPI to encourage incorporation of the MPI as a useful tool in clinical practice.

Use of the Foetal Myocardial Performance Index in monochorionic, diamniotic twin pregnancy: a prospective cohort and nested case-control study

Abstract Aims: Assess clinical utility of the foetal Myocardial Performance Index (MPI) in evaluation and management of monochorionic, diamniotic twin (MCDA) pregnancies. Methods: Prospective cohort of (a) initially uncomplicated MCDA (b) Complicated MCDA, including twin–twin transfusion syndrome (TTTS), selective intrauterine growth restriction (sIUGR), and liquor and/or growth discordance (L/GD) not meeting TTTS or sIUGR criteria. TTTS and sIUGR were case-control matched. Routine Dopplers and MPI were taken and correlated to diagnosis and final outcome. Results: Twenty-six always uncomplicated pairs, 51 always complicated pairs, and seven uncomplicated to pathological pairs were included. TTTS recipient (n = 25) left and right MPI and intertwin difference (ITD) were significantly elevated, however, were already elevated in Stage I (n = 10), and did not predict progression or pregnancy outcome. sIUGR MPI (n = 11) did not differ significantly from control. Of 15-L/GD pairs, two that progressed to TTTS had significantly higher left and right MPI values in the future recipient (0.61 and 0.72) versus future sIUGR larger twins (0.48 and 0.51) or stable L/GD (0.47 and 0.52): p < .01 for all comparisons. Conclusions: In this cohort, MPI did not add substantial diagnostic/prognostic information to current routine evaluation in established TTTS or sIUGR though potentially differentiated L/GD cases progressing to TTTS.

Novel spatial–temporal image correlation derived indices of tissue vascular impedance: A variability study

4D (3D + time) indices of tissue impedance using power Doppler (PD) ultrasound (US) can be measured with spatial–temporal image correlation (STIC) imaging. We wished to evaluate their repeatability and their influence under changes to US machine settings and regional differences within the placenta.