Role of four-dimensional echocardiography with high-definition flow imaging and spatiotemporal image correlation in detecting fetal pulmonary veins

Slow flow HD and traditional CDFI technologies in identifying pulmonary veins in the first trimester

OBJECTIVE

This study aims to assess the feasibility and effectiveness of color doppler flow imaging (CDFI) technology and the Slow Flow HD imaging technique in identifying fetal pulmonary veins (PVs) in the first trimester (11-13 + 6 weeks), and further explore the factors affecting fetal pulmonary vein identification in early pregnancy.

METHODS

Echocardiography and scanning of PVs were performed in 240 normal singleton fetuses in early pregnancy by using CDFI and slow flow HD techniques, to compare the ability of two methods to identify the PVs. Slow Flow HD technology was used to further investigate the difference of PVs identification at different gestational ages [group I (11-11 + 6 weeks), group II (12-12 + 6 weeks), group III (13-13 + 6 weeks)] and with different maternal body mass indices (BMI) (≥ 25 and < 25). In 31 cases of 240 fetuses, transvaginal ultrasonography was added due to maternal habitus or significant retroversion of the uterus, and the difference in PVs identification between transabdominal and transvaginal examination was analyzed.

RESULTS

Successful PVs identification rates via CDFI and Slow Flow HD were 32.0% and 88.3%, respectively (p < 0.05). The identification rate of at least one and two pulmonary veins in Slow Flow HD was 88.3% and 76.2%, and all four pulmonary veins in 11.6% (p < 0.05). The identification rate of group I, II and III were 76.4%, 88.9% and 96.0%, respectively. The identification rate was 45.1% in the transabdominal ultrasound group and 83.8% in the transvaginal ultrasound group. The identification rate was 62.5% in the BMI ≥ 25 group and 94.7% in the BMI < 25 group (p < 0.05).

CONCLUSIONS

Slow Flow HD can detect PVs in early pregnancy more often than using CDFI. Slow Flow HD is a feasible and effective imaging technique for evaluating PVs in early pregnancy.

Fetal Pulmonary Venous Return: From Basic Research to the Clinical Value of Doppler Assessment

The fetal pulmonary circulation represents less than 25% of the fetal cardiac output. In comparison with the pulmonary arteries, studies on pulmonary veins are few and limited, and many questions remain to be answered. The literature reports that pulmonary veins play an important role in regulating vascular flow, forming an active segment of the pulmonary circulation. The development of more sophisticated ultrasonography technology has allowed the investigation of the extraparenchymal pulmonary veins and their waveform. The recognition of the pulmonary vein anatomy in echocardiography is important for the diagnosis of anomalous pulmonary venous connections, with a significant impact on prognosis. On the other hand, the identification of the normal pulmonary vein waveform seems to be a reliable way to study left heart function, with potential applicability in fetal and maternal pathology. Thus, the goal of this narrative review was to provide a clinically oriented perspective of the available literature on this topic.

Feasibility of Transabdominal Real-time CDFI and HDFI Techniques for Fetal Pulmonary Vein Display in the First Trimester

OBJECTIVE

This study aimed to assess the feasibility and usefulness of transabdominal color Doppler flow imaging (CDFI) technology and the high-definition flow imaging (HDFI) technique in detecting fetal pulmonary veins (PVs) in the first trimester (11-13₊₆ weeks).

METHODS

From December 2018 to October 2019, 328 pregnant women with 328 normal singleton fetuses (crown-rump length: 45-84 mm) who had undergone CDFI and HDFI scans for fetal heart and vessel examination were enrolled in this study. The cases were divided into three groups according to the gestational age: group A, 11⁺⁰ -11⁺⁶ weeks; group B, 12⁺⁰ -12⁺⁶ weeks; and group C, 13⁺⁰ -13⁺⁶ weeks. Baseline sonograms and CDFI and HDFI images were analyzed by two senior radiologists independently and blindly. The abilities of CDFI and HDFI to display PVs were compared.

RESULTS

Successful PV display rates via CDFI and HDFI were 2.3% and 68.2% (P<0.01), 22.4% and 82.4% (P<0.01), 41.5% and 91.2% (P<0.01) for group A, group B, and group C, respectively. The total successful display rates for the two methods were 28.9% (CDFI) and 84.8% (HDFI) (P<0.01).

CONCLUSIONS

The HDFI technique is more valuable than CDFI for detecting PVs in early pregnancy (11-13⁺⁶ weeks). HDFI can detect at least one PV in all cases and may be used to detect pulmonary venous anomalies early.

Prenatal diagnosis of right aortic arch and aberrant left subclavian artery in association with bilateral ductus arteriosus by two-and four-dimensional echocardiography: a case of rare vascular ring and review of literature

The incidence of bilateral ductus arteriosus is sporadically reported in the uterus, and right aortic arch with aberrant of the left subclavian artery in association with bilateral ductus arteriosus is therefore extremely rare. We describe a case of right aortic arch and aberrant left subclavian artery associated with bilateral ductus arteriosus. Scanning around the three-vessel and trachea view to search for an "O" shape and a "U" shape vascular ring is essential for the diagnosis, which reveals vascular structures coursing around the trachea. Four-dimensional echocardiography with high-definition flow imaging and spatiotemporal image correlation technique illustrates the spatial relationships of these vessels and the trachea, which should be considered as a complementary modality in fetal cardiac examinations.

Two- and four-dimensional echocardiography with high-definition flow imaging and spatiotemporal image correlation in the diagnosis of fetal isolated partial anomalous pulmonary venous connection

Partial anomalous pulmonary venous connection (PAPVC) is a rare malformation. We describe a case of PAPVC, in which the left pulmonary veins coursed to the left innominate vein through a vertical vein and finally drained into the right superior vena cava; the right pulmonary veins were connected to the left atrium. Tracing the origin and destination of abnormal vessels presented at the three-vessel and trachea view is useful for the diagnosis. Four-dimensional echocardiography with high-definition flow imaging and spatiotemporal image correlation facilitates the identification of the drainage of fetal pulmonary veins, which should be considered as a complementary modality in obstetric ultrasonic examination when cardiac abnormalities are suspected.

Prenatal screening of fetal ventriculoarterial connections: benefits of 4D technique in fetal heart imaging

Background

Identification of prenatal ventriculoarterial connections in fetuses with conotruncal anomalies (CTA) remains one of the greatest challenges for sonographers performing screening examinations. Herein, we propose a novel protocol of 4D volume analysis that identifies ventriculoarterial connections and evaluate its clinical utility in routine screenings.

Methods

Twenty-nine cases of transposition of the great arteries (TGA), 22 cases of double-outlet right ventricle (DORV), 36 cases of tetralogy of Fallot (TOF), 14 cases of truncus arteriosus (TCA), and randomly selected 70 normal fetuses were reviewed in this study. All cases were evaluated using 2D data alone (2D method), post-processing volumes with no exact algorithm (4D-1 method), or with the proposed algorithm (4D-2 method), or using the 2D and 4D data together (combined method). Comparisons were made to evaluate the detection rate of ventriculoarterial connections for these different methods.

Results

During 18–28 gestational weeks, the detection rate of 4D-2 modality was satisfactory. The detection rate of the combined method was significantly higher than 2D method in the identification of TGA, TOF, and TCA. The detection rate of 4D-1 method was significantly lower than 4D −2 modality for CTA fetuses. During late pregnancy, the detection rate for both 4D modalities was very low due to the poor quality of the 4D volumes.

Conclusions

We proposed a detailed protocol, which allowed the examiner to identify fetal ventriculoarterial connections by 4D volumes. Inclusion of blood information into the volumes improved diagnosis. Our findings suggest that the incorporation of 4D STIC into routine screenings could improve the detection for TGA, TOF, and TCA.

Electronic supplementary material

The online version of this article (doi:10.1186/s12947-017-0108-5) contains supplementary material, which is available to authorized users.