The transverse four-chamber view for the assessment of atrial tissue deformation in the fetus.

AIMS: To determine if atrial tissue deformation (peak strain, PS) and time to peak strain (TTPS) can be assessed in the fetus, with identification of best echocardiographic plane. MATERIALS AND METHODS: Pulsed-wave tissue Doppler study of a longitudinal and a transverse four-chamber view (FCV) in each of 20 healthy fetuses. Determination of PS and TTPS in regions of interest (ROI), viz., lateral walls of the right and left atria (RA, LA); comparison of values depending on section plane, with results-based discussion of the physiology of fetal atrial deformation and of possible clinical uses. RESULTS: PS and TTPS could be determined on transverse FCV in 91% of subjects and in 61% on longitudinal FCV. Transverse PS and TTPS were significantly higher than longitudinal (p = 0.0001). Transverse PS was significantly higher in RA than in LA (26.9% vs. 17.3%, p = 0.034), and transverse TTPS was significantly shorter in RA than in LA (p = 0.034). CONCLUSION: Atrial radial PS and TTPS determinations are possible in the fetus. The transverse FCV is best suited for these. The highest PS values and shortest TTPS values are found in ROI representing the RA. Our findings may contribute to detailed intrauterine assessment of atrial and ventricular myocardial function.

An automated assay for the assessment of cardiac arrest in fish embryo.

Studies on fish embryo models are widely developed in research. They are used in several research fields including drug discovery or environmental toxicology. In this article, we propose an entirely automated assay to detect cardiac arrest in Medaka (Oryzias latipes) based on image analysis. We propose a multi-scale pipeline based on mathematical morphology. Starting from video sequences of entire wells in 24-well plates, we focus on the embryo, detect its heart, and ascertain whether or not the heart is beating based on intensity variation analysis. Our image analysis pipeline only uses commonly available operators. It has a low computational cost, allowing analysis at the same rate as acquisition. From an initial dataset of 3192 videos, 660 were discarded as unusable (20.7%), 655 of them correctly so (99.25%) and only 5 incorrectly so (0.75%). The 2532 remaining videos were used for our test. On these, 45 errors were made, leading to a success rate of 98.23%.

Image-Derived Assessment of Left Ventricular Mass in Fetal Myocardial Hypertrophy by 4-Dimensional Echocardiography: An In Vitro Study.

OBJECTIVES: This study tested the accuracy of new 4-dimensional fetal echocardiography to evaluate left ventricular (LV) mass in an experimental model of fetal myocardial hypertrophy. METHODS: Ten fresh rabbit hearts were studied. Fetal myocardial hypertrophy was simulated by fixing different amounts of myocardial tissue to the LV epicardium. A small latex balloon was mounted on vinyl tubing and fixed within each LV cavity. The proximal end of the tube was attached to a pulsatile pump apparatus. The pump was calibrated to deliver stroke volumes of 2 and 4 mL at stroke rates of 60 and 120 beats per minute (bpm). Four-dimensional data were acquired and analyzed with quantification software. Reference values for LV mass were determined by the displacement method. RESULTS: Echo-derived measurements of LV mass showed good correlations with reference values at all stroke rates and stroke volumes: at 2 mL and 60 bpm, r = 0.95; at 2 mL and 120 bpm, r = 0.95; at 4 mL and 60 bpm, r = 0.93; and at 4 mL and 120 bpm, r = 0.95 (P< .01 for all values). There was also excellent interobserver (r = 0.98; mean difference of -0.32 g; -4.4% of the mean) and intraobserver (r = 0.98; mean difference of -0.28 g; -3.8% of the mean) agreement. CONCLUSIONS: In this controlled in vitro study, high-resolution 4-dimensional echocardiography was shown to accurately assess LV mass and have the potential to evaluate fetal myocardial hypertrophy.

Functional assessment of the fetal heart: a review.

The purpose of this review is to evaluate the current modalities available for the assessment of fetal cardiac function. The unique anatomy and physiology of the fetal circulation are described, with reference to the difference between in-utero and ex-utero life. M-mode, early/atrial ratio, myocardial performance index, three-dimensional and four-dimensional ultrasound, tissue Doppler including strain and strain rate, speckle tracking, magnetic resonance imaging and venous flow assessment are described. The modalities are analyzed from the perspective of the clinician and certain questions are posed. Does the modality assess systolic function, diastolic function or both? Is it applicable to both ventricles? Does it require extensive post-processing or additional hardware, or does it make use of technology already available to the average practitioner? The reproducibility and reliability of the techniques are evaluated, with reference to their utility in clinical decision-making. Finally, directions for future research are proposed.

Functional assessment of the evolution of congenital heart disease in utero.

PURPOSE OF REVIEW: This article reviews recent developments in the assessment of changes in structure and function in the fetal heart with the focus on congenital heart disease malformations. RECENT FINDINGS: Use of the combination of the cardiovascular profile score, the biophysical profile score and additional physiological measurements with Doppler echocardiography have allowed better characterization of disease states and the changes that can occur in utero during the last two trimesters of gestation. SUMMARY: A comprehensive examination of the structure and function of the fetal heart together with the evaluation of other parameters of fetal wellbeing are necessary for comprehensive assessment of the evolution of congenital heart disease in utero. Only such an objective surveillance can elucidate the pathophysiology and natural history, guide appropriate timing of intervention, monitor the success of any in-utero therapy, and predict perinatal outcome.

Uterine contractions might increase heart preload in the recipient fetus in early-onset twin-twin transfusion syndrome: an ultrasound assessment.

OBJECTIVES: Uterine contractions (UC) in twin pregnancy are often experienced, yet the effects of UC in twin-twin transfusion syndrome (TTTS) remain to be clarified. The recipient heart preload condition and the effects of UC were evaluated and the final objective was to clarify the effects of tocolysis. METHODS: Firstly, the preload indexes (PLIs) and cardiothoracic area ratios (CTARs) were analyzed on both fetuses of 10 TTTS cases, aged from 14 to 28 gestational weeks in stage III/IV cases for evaluating the preload condition. Then, the PLIs in the presence and absence of UC in the recipient fetuses were determined to evaluate the difference. RESULTS: The PLIs of the recipient and the donor fetuses were 0.78 +/- 0.34 (n = 163) and 0.35 +/- 0.13 (n = 71) respectively. The CTARs were 30.2 +/- 6.1 (n = 62) and 23.4 +/- 5.4 (n = 62) respectively. The PLIs in the absence and presence of UC in the recipient fetuses were 0.69 +/- 0.29 and 0.99 +/- 0.38 (n = 35). All above comparisons showed highly significant differences (p < 0.0001). CONCLUSION: The recipient fetuses have signs of cardiac dilatation and a high-preload condition. UC transiently further raises high-preload conditions of the recipient fetus. Thus, tocolysis may be necessary for management in cases of early-onset severe TTTS.