Nomograms of Fetal Right Ventricular Fractional Area Change by 2D Echocardiography

Fetal Echocardiographic Evaluation of Tricuspid Valve and Right Ventricular Function Including Global Longitudinal Strain in Hypoplastic Left Heart Syndrome and Association with Postnatal Outcomes

Despite significant advancements in the care of patients with hypoplastic left heart syndrome (HLHS) morbidity and mortality remain high. Postnatal right ventricular dysfunction and tricuspid regurgitation (TR) are associated with worse outcomes in HLHS. We aim to determine if right ventricle functional parameters and TR on fetal echocardiogram are associated with postnatal outcomes in HLHS patients. Retrospective review was performed on all fetuses with HLHS from 2014 to 2022 at our institution. Initial and follow up fetal echocardiogram measurements of right ventricular myocardial performance index (MPI), fractional area change (FAC) and global longitudinal strain (GLS) were retrospectively measured. The presence and severity of TR was recorded from the fetal echocardiogram reports. Postnatal outcomes including transplant-free survival, hospital length of stay > 30 days after initial palliation and need for bidirectional Glenn at < 4 months were reviewed. Forty-three subjects met inclusion criteria. Mean gestational age at presentation was 26.1 ± 5.9 weeks. Nine subjects died and 3 required heart transplantation. Initial fetal echocardiogram MPI was significantly lower (better) (0.36 ± 0.06 vs 0.44 ± 0.11; p =  < 0.001) and FAC was significantly higher (better) (45 ± 6% vs 40 ± 8%; p = 0.035) in transplant-free survivors. Fetal right ventricular GLS and presence of mild TR were not associated with postnatal outcome. In fetuses with HLHS, abnormal MPI and right ventricular FAC are associated with decreased transplant-free survival. There was no observed association between GLS and postnatal outcomes. To our knowledge this is the first study examining fetal right ventricular function and GLS in HLHS patients and its link to postnatal outcomes.

Challenges in clinical identification of right ventricular dysfunction in preterm infants with persistent pulmonary hypertension of the newborn

BACKGROUND

Right ventricular dysfunction, typically qualitatively diagnosed (Q-RVd) in preterm infants, requires echocardiography which is not always acutely available. We aimed to identify clinical indices of Q-RVd in very preterm infants (gestational age, GA <32 weeks) with persistent pulmonary hypertension of newborn (PPHN) and examine the reliability and validity of Q-RVd.

METHODS

Forty-seven infants with mean ± SD GA of 26.8 ± 2.7 weeks who had targeted neonatal echocardiography (TNE) ≤72 h old, during PPHN, were retrospectively studied. Three standard TNE clips were reviewed by two blinded assessors, and infants categorized as Q-RVd if moderate-severe RVd was diagnosed on ≥2 clips. Cardiopulmonary clinical indices at TNE and quantitative RV functional markers were compared between Q-RVd vs. no-RVd groups. Potential quantitative RVd definitions examined by classifying each measurement as "low" or "normal" using published data. Inter-rater agreement for Q-RVd assessed using Kappa statistics.

RESULTS

Mean age at TNE was 25.3 ± 20.4 h with Q-RVd diagnosed in 19(40 %) infants. Q-RVd group demonstrated higher peak oxygen requirements (96 ± 9 % vs. 84 ± 16 %, p < 0.01); however, no clinical parameters at TNE differentiated the groups. Quantitative measures were lower in Q-RVd patients, confirming classification validity. Among tested quantitative definitions, low RV stroke volume was associated with lower systolic blood pressure (41±7 vs. 47±9 mmHg, p = 0.02) and higher shock index (4.02±0.80 vs. 3.44±0.72, p = 0.02). Kappa for Q-RVd was 0.55 (95%CI 0.32-0.77).

CONCLUSIONS

The non-specific nature of clinical markers of RVd in preterm infants with PPHN necessitates echocardiographic diagnosis of RVd. Studies should examine prognostic relevance of RVd and establish outcome-based quantitative definitions in preterm infants.

Fetal left-atrial posterior-space-to-diagonal ratio at 17-37 weeks' gestation for prediction of total anomalous pulmonary venous connection

OBJECTIVES

To develop normative data for the left-atrial posterior-space-to-diagonal (LAPSD) ratio and post-left atrium space (PLAS) index in fetuses from 17 to 37 weeks' gestation, and determine the optimal cut-offs of the LAPSD ratio and PLAS index to discriminate between normal fetuses and those with total anomalous pulmonary venous connection (TAPVC).

METHODS

This was a prospective cross-sectional assessment of 428 structurally normal fetuses between 17 and 37 weeks' gestation and a retrospective study of 27 TAPVC fetuses. The fetal LAPSD ratio was calculated by dividing the left atrium-descending aorta distance (LDD) by the left atrial diagonal diameter (LA). The PLAS index was calculated as the ratio of the LDD to the descending aorta diameter (DA). Pearson's correlation analysis was used to examine the correlation of cardiac parameters with gestational age (GA) and fetal somatic growth. The PLAS index and LAPSD ratio were compared between the normal and TAPVC groups to assess their usefulness in the prenatal diagnosis of TAPVC.

RESULTS

LDD, LA and DA measures showed moderate to strong positive correlation, whereas both the LAPSD ratio and PLAS index showed a slight decrease with increasing GA and biometric variables. The fetal LAPSD ratio and PLAS index in TAPVC cases were significantly greater compared with those of fetuses with a normal heart (both P < 0.001). There were no significant differences in the PLAS index and LAPSD ratio between the isolated and complex TAPVC groups (both P = 1). No significant associations of the PLAS index and LAPSD ratio with fetal gender, four-chamber view type (apical, basal or lateral) or TAPVC type were found. Using values of ≥ 0.35 for the LAPSD ratio and of ≥ 1 for the PLAS index exhibited similar excellent diagnostic performance, with a sensitivity of 100% and specificity of 97.0% or 95.1% for detecting TAPVC.

CONCLUSIONS

Our study demonstrates that the LAPSD ratio is a practical and effective screening tool for diagnosing fetal TAPVC, similar to the PLAS index. Incorporating these parameters into routine cardiac scanning may enhance the prenatal detection of TAPVC. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Cord Blood Cardiovascular Biomarkers in Left-Sided Congenital Heart Disease

Fetal echocardiography has limited prognostic ability in the evaluation of left-sided congenital heart defects (left heart defects). Cord blood cardiovascular biomarkers could improve the prognostic evaluation of left heart defects. A multicenter prospective cohort (2013−2019) including fetuses with left heart defects (aortic coarctation, aortic stenosis, hypoplastic left heart, and multilevel obstruction (complex left heart defects) subdivided according to their outcome (favorable vs. poor), and control fetuses were evaluated in the third trimester of pregnancy at three referral centers in Spain. Poor outcome was defined as univentricular palliation, heart transplant, or death. Cord blood concentrations of N-terminal precursor of B-type natriuretic peptide, Troponin I, transforming growth factor β, placental growth factor, and soluble fms-like tyrosine kinase-1 were determined. A total of 45 fetuses with left heart defects (29 favorable and 16 poor outcomes) and 35 normal fetuses were included, with a median follow-up of 3.1 years (interquartile range 1.4−3.9). Left heart defects with favorable outcome showed markedly increased cord blood transforming growth factor β (normal heart median 15.5 ng/mL (6.8−21.4) vs. favorable outcome 51.7 ng/mL (13.8−73.9) vs. poor outcome 25.1 ng/mL (6.9−39.0), p = 0.001) and decreased placental growth factor concentrations (normal heart 17.9 pg/mL (13.8−23.9) vs. favorable outcome 12.8 pg/mL (11.7−13.6) vs. poor outcome 11.0 pg/mL (8.8−15.4), p < 0.001). Poor outcome left heart defects had higher N-terminal precursor of B-type natriuretic peptide (normal heart 508.0 pg/mL (287.5−776.3) vs. favorable outcome 617.0 pg/mL (389.8−1087.8) vs. poor outcome 1450.0 pg/mL (919.0−1645.0), p = 0.001) and drastically reduced soluble fms-like tyrosine kinase-1 concentrations (normal heart 1929.7 pg/mL (1364.3−2715.8) vs. favorable outcome (1848.3 pg/mL (646.9−2313.6) vs. poor outcome 259.0 pg/mL (182.0−606.0), p < 0.001). Results showed that fetuses with left heart defects present a distinct cord blood biomarker profile according to their outcome.

Feasibility of 4D-Spatio Temporal Image Correlation (STIC) in the Comprehensive Assessment of the Fetal Heart Using FetalHQ®

Fetal Heart Quantification (FetalHQ®) is a novel speckle tracking software that permits the study of global and regional ventricular shape and function from a 2D four-chamber-view loop. The 4D-Spatio Temporal Image Correlation (STIC) modality enables the offline analysis of optimized and perfectly aligned cardiac planes. We aimed to evaluate the feasibility and reproducibility of 4D-STIC speckle tracking echocardiography (STE) using FetalHQ® and to compare it to 2D STE. We conducted a prospective study including 31 low-risk singleton pregnancies between 20 and 40 weeks of gestation. Four-chamber view volumes and 2D clips were acquired with an apex pointing at 45° and with a frame rate higher than 60 Hz. Morphometric and functional echocardiography was performed by FetalHQ®. Intra- and interobserver reproducibility were evaluated by the intraclass correlation coefficient (ICC). Our results showed excellent reproducibility (ICC > 0.900) for morphometric evaluation (biventricular area, longitudinal and transverse diameters). Reproducibility was also good (ICC > 0.800) for functional evaluation (biventricular strain, Fractional Area Change, left ventricle volumes, ejection fraction and cardiac output). On the contrary, the study of the sphericity index and shortening fraction of the different ventricular segments showed lower reproducibility (ICC < 0.800). To conclude, 4D-STIC is feasible, reproducible and comparable to 2D echocardiography for the assessment of cardiac morphometry and function.

Prescriptive standards of echocardiographic morphometric and functional parameters in uncomplicated monochorionic diamniotic fetuses

OBJECTIVE

To create prescriptive standards of cardiac morphometric and functional parameters in a cohort of uncomplicated monochorionic diamniotic (MCDA) twins.

METHOD

Fetal echocardiography was performed in a cohort of uncomplicated monochorionic twin fetuses scanned longitudinally, including comprehensive morphometric and functional parameters, using 2-D imaging, M-mode and conventional Doppler. A multilevel polynomial hierarchical model adjusted by gestational age and estimated fetal weight was used to fit each cardiac parameter.

RESULTS

The global heart dimensions including the atrial and ventricular areas, the ventricles dimensions and myocardial wall thicknesses and most of the functional parameters, such as the longitudinal myocardial motion and the biventricular cardiac output showed a positive quadratic increment throughout pregnancy. On the other hand, the left ejection fraction, shortening fraction and right fractional area change decreased with gestational age. Scatterplots for the main structural and functional parameters and ratios by gestational age, with mean, 5th, 10th, 90th, and 95th percentiles are provided. Regression equations by estimated fetal weight are also created.

CONCLUSION

We provide specific comprehensive echocardiographic prescriptive standards for uncomplicated MCDA twin fetuses following current standardized methodology. The implementation of these charts will potentially help to better identify abnormal cardiovascular parameters associated to monochorionic complications.