Background: To evaluate the clinical value of foetal intelligent navigation echocardiography (5D Heart) for the display of key diagnostic elements in basic sections.
Methods: 3D volume datasets of 182 normal singleton foetuses were acquired with a four chamber view by using a volume probe. After processing the datasets by using 5D Heart, eight cardiac diagnostic planes were demonstrated, and the image qualities of the key diagnostic elements were graded by 3 doctors with different experiences in performing foetal echocardiography.
Results: A total of 231 volume datasets acquired from the 182 normal foetuses were used for 5D Heart analysis and display. The success rate of 8 standard diagnostic views was 88.2%, and the success rate of each diagnostic view was 55.8-99.2% and 70.7-99.0% for the random four chamber view as the initial section and for the apical four chamber view as the initial section, respectively. The success rate of each diagnostic element in the 8 diagnostic sections obtained by 5D Heart was 58.9%~ 100%. Excellent agreement was found between experienced sonographers and less-experienced sonographers (kappa> 0.769). Inter- and intra-observer agreement were substantial to near-perfect, kappa values ranging from 0.612 to 1.000 (Cohen’s kappa).
Conclusions: 5D Heart can significantly improve the image quality of key diagnostic elements in foetal echocardiography with low operator dependency and good reproducibility.
Conflict of interest statement
The authors declare that they have no competing interests.
Fig. 1 Seven anatomical structures within the heart that are marked using Anatomic Box®. The seven anatomical structures were as follows: 1) cross-section of the aorta at the level of the stomach; 2) cross-section of the aorta at the level of the four chamber view; 3) crux; 4) right atrial wall; 5) pulmonary valve; 6) cross-section of the superior vena cava; and 7) transverse aortic arch
Fig. 2 The nine diagnostic sections displayed by 5D Heart. The 9 diagnostic sections displayed by 5D Heart are as follows: 1) 3VT; 2) four chamber; 3) five chamber; 4) left ventricular outflow tract; 5) short-axis view of great vessels/right ventricular outflow tract; 6) abdomen/stomach; 7) ductal arch; 8) aortic arch; and 9) superior and inferior vena cava. STIC volume datasets of the foetal heart showing nine cardiac diagnostic planes with automatic labelling with 5D Heart in each plane, anatomical structures, foetal left and right sides and cranial and caudal ends
Fig. 3 The three grades of image quality. A structure of interest that could be imaged clearly scored 3 points (c); adequately, 2 points (b); and unidentifiable, 1 point (a)
Fig. 4 The components of foetal heart direction (n = 231). 1 to 12 means the apex of the foetal heart points between the 1- and 12- o’clock, and the rate of each direction is shown in the pie chart
Fig. 5 Number of foetal echocardiography views successfully obtained in each foetal heart with 5D Heart (n = 50). 3 to 8 means the total number of diagnostic planes retrieved from one foetus, and the success rates are shown in the pie chart