Diagnostic Validity and Reliability of Low-Dose Prospective ECG-Triggering Cardiac CT in Preoperative Assessment of Complex Congenital Heart Diseases (CHDs)

Abstract

For the precise preoperative evaluation of complex congenital heart diseases (CHDs) with reduced radiation dose exposure, we assessed the diagnostic validity and reliability of low-dose prospective ECG-gated cardiac CT (CCT). Forty-two individuals with complex CHDs who underwent preoperative CCT as part of a prospective study were included. Each CCT image was examined independently by two radiologists. The primary reference for assessing the diagnostic validity of the CCT was the post-operative data. Infants and neonates were the most common age group suffering from complex CHDs. The mean volume of the CT dose index was 1.44 ± 0.47 mGy, the mean value of the dose-length product was 14.13 ± 5.4 mGy*cm, and the mean value of the effective radiation dose was 0.58 ± 0.13 mSv. The sensitivity, specificity, PPV, NPV, and accuracy of the low-dose prospective ECG-gated CCT for identifying complex CHDs were 95.6%, 98%, 97%, 97%, and 97% for reader 1 and 92.6%, 97%, 95.5%, 95.1%, and 95.2% for reader 2, respectively. The overall inter-reader agreement for interpreting the cardiac CCTs was good (κ = 0.74). According to the results of our investigation, low-dose prospective ECG-gated CCT is a useful and trustworthy method for assessing coronary arteries and making a precise preoperative diagnosis of complex CHDs.

Keywords: cardiac CT; complex CHDs; low-dose; prospective ECG-gated.

Figure 1

Flow chart of the study.

Figure 2

A 5-month-old male patient with truncus arteriosus Type I. (a) Curved MIP and (b) 3D-VR image showing a common arterial trunk arising with a single prominent truncal valve overriding both ventricles. The trunk measures 9 mm in length and 19 mm in diameter, along with cardiomegaly with dilatation of all chambers, predominantly right-sided, and VSD with overriding prominent truncal valve. (c) 3D-VR image showing a short MPA trunk arising from the left posterolateral aspect of the common trunk. This short MPA trunk measures 3.5 mm in length and 10 mm in diameter. The RPA shows a relatively tight segment (arrow) measuring approximately 2.5 mm in length and 4.5 mm in diameter at its origin. (d) 3D-VR image at the level of the MPA origin. The ascending aorta is seen arising from the right lateral aspect of this trunk.

Figure 3

A one-month-old female patient with total anomalous pulmonary venous return (right side→SVC/left side→common vein→portal vein). (a) Coronal 3D-VR image revealing left upper and lower pulmonary veins communicated to form one common vein passing downward right to the aorta to join the portal vein after a 40 mm course and a 90-degree angle curve. (b) Curved MIP image revealing right upper and lower pulmonary veins joined at the entry site at the base of the SVC just beside the junction of a large azygous vein. (c) Axial MIP image revealing patent foramen ovale of 3 mm with a right to left shunt. There was no pulmonary vein connection to the left atrium.