Coronary magnetic resonance angiography (CMRA) is being increasingly used in pediatric patients with congenital coronary artery anomalies (CAAs). However, the data on the free-breathing self-navigation technique, which has the potential to simplify the acquisition plan with a high success rate at 3T, remain scarce. This study investigated the clinical application value of self-navigated (sNAV) CMRA at 3T in pediatric patients with suspected CAAs and compared it to conventional diaphragmatic-navigated (dNAV) CMRA.
From April 2019 to March 2022, we enrolled 65 pediatric patients (38 males and 27 females; mean age 8.5±4.4 years) with suspected CAAs in this prospective study. All patients underwent both dNAV and sNAV sequences in random order with gradient recalled echo (GRE) sequence during free breathing, with 39 (20 males and 19 females; mean age 10.2±3.6 years) of them additionally undergoing coronary computed tomography angiography (CCTA) or invasive coronary angiography (ICA). We measured and compared the success rate, scan time, visual score of the 9 main coronary artery segments, vessel sharpness, and vessel length between the two sequences. The diagnostic accuracy was compared using CCTA or ICA as a reference.
The success rate of sNAV-CMRA (65/65, 100%) was higher than that of dNAV-CMRA (61/65, 93.8%) (P<0.001), and the scan time of sNAV-CMRA (7.3±2.5 min) was significantly shorter than that of dNAV-CMRA (9.1±3.6 min) (P=0.002). The acquisition efficiency of dNAV-CMRA was 40.5%±12.9%, while for sNAV-CMRA, 100% acquisition efficiency was achieved. There was no significant difference in vessel length of any of the coronary arteries, visual score, or vessel sharpness of the left circumflex coronary artery (LCX) between the two sequences (all P values >0.050). The visual score and vessel sharpness of the right coronary artery and left anterior descending coronary artery (LAD) were significantly improved in dNAV-CMRA compared with sNAV-CMRA (all P values <0.050). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the detection of CAAs were not significantly different between the two sequences (all P values >0.050).
Our findings demonstrated that both sNAV and dNAV in CMRA provide clinical application value in pediatric patients with CAAs and have similar diagnostic performance. Although the image quality of sNAV-CMRA is slightly inferior compared to that of dNAV-CMRA, sNAV-CMRA allows for a simpler scanning procedure.