Low-Dose Dual-Source Computed Tomography for Evaluating Persistent Truncus Arteriosus Associated with Cardiovascular Anomalies: Comparison with Transthoracic Echocardiography

Abstract

BackgroundTo assess the morphological features of persistent truncus arteriosus (PTA) on low-dose dual-source computed tomography (DSCT) and compare its diagnostic value for associated cardiovascular anomalies with that of transthoracic echocardiography (TTE).Methods:Twenty-four PTA patients were enrolled in this retrospective study. The types of PTA, diameters of the truncus artery (TA), main pulmonary artery (MPA), right pulmonary artery (RPA), left pulmonary artery (LPA), and ventricular septal defect (VSD) on DSCT were recorded. Besides, all associated cardiovascular abnormalities were assessed. The diagnostic performance of DSCT and TTE for associated anomalies were compared. The effective doses of DSCT were calculated.Results:Four types were found: type A1(n=13/24, 54.17%), type A2(n=7/24, 29.16%), type A3（n=3/24, 12.50%）and type A4(n=1/24,4.17%). The mean diameter of VSD, TA, MPA, RPA, and LPA was 1.47±0.56cm, 3.92±1.56cm, 2.27±1.65cm, 1.48±0.74cm and 1.38±0.66cm, respectively. 78 associated cardiovascular anomalies were confirmed. The most common associated abnormalities were VSD (100%), right-sided aortic arch (33.33%) and aortopulmonary collateral vessels (29.17%). Although TTE was better at diagnosing intracardiac anomalies (accuracy:99.17% vs. 95%; sensitivity: 97.06% vs. 88.24%; specificity: 100% vs. 97.67%), DSCT had an advantage in diagnosing the associated cardiovascular abnormalities (accuracy: 98.61% vs. 96.07%; sensitivity: 94.87% vs. 82.05%; specificity: 99.44% vs. 99.15%). The estimated mean effective doses was 0.98±0.37mSv (＜1mSv). Conclusions:Low-dose DSCT could accurately confirm the morphological features of PTA. Compared to TTE, low-dose DSCT is a better diagnostic tool for associated cardiovascular abnormalities. Combining with TTE will be beneficial to provide more accurate information for clinical interventions.