Significance of systolic-phase imaging on full-phase ECG-gated CT angiography to detect intimal tears in aortic dissection

Abstract

Purpose For patients with aortic dissection (AD) and intramural hematoma (IMH), the optimal cardiac phase to detect intimal tears (IT) and ulcer-like projections (ULP) on retrospective electrocardiogram (ECG)-gated computed tomography angiography (CTA) remains unclear. The purpose of this study was to compare the accuracy of retrospective ECG-gated CTA for detecting IT in AD and ULP in IMH between each cardiac phase. Materials and methods A total of 75 consecutive patients with AD and IMH of the thoracic aorta were enrolled in this single-center retrospective study. The diagnostic performance to detect IT and ULP in the thoracic aortic regions (including the ascending aorta, aortic arch, and proximal and distal descending aorta) was compared in each cardiac phase on retrospective ECG-gated CTA. Results In the systolic phase (20%), the accuracy, sensitivity, and specificity to detect IT in AD was 64% (95% confidence interval [CI] 56–72%), 69% (95%CI 60–78%), and 25% (95%CI 3.3–45%), respectively. In the diastolic phase (70%), the accuracy, sensitivity, and specificity to detect IT in AD was 52% (95%CI 43–60%), 52% (95%CI 42–61%), and 50% (95%CI 25–75%), respectively. The accuracy to detect IT in AD on ECG-gated CTA was significantly higher in the systolic phase than that in the diastolic phase (P = 0.025). However, there were no differences in the accuracy (83%; 95%CI 78–89%), sensitivity (71%; 95%CI 62–80%), or specificity (100%; 95%CI 100%) to detect ULP in IMH between the cardiac cycle phases. Conclusion Although it is currently recommended for routine diagnosis of AD and IMH, single-diastolic-phase ECG-gated CTA has risk to miss some IT in AD that are detectable in the systolic phase on full-phase ECG-gated CTA. This information is critical for determining the optimal treatment strategy for AD.

Progress of CT aortic angiography combined with coronary artery in the evaluation of acute aortic syndrome

“…Although CT technologies have been developed fast, the diagnosis of AAS is increasingly dependent on aortic CTA in the clinic. Because of the complexity of the disease (accompanied by complications), a single aortic CTA cannot completely deal with the clinical problems (14,(26)(27)(28)(29), for example, type I AD needs to perform as follows: (a) confirm whether there is an intimal film; (b) evaluate the degree of disease according to the aortic structure; (c) identify the true or false lumen; (d) judge the location of the breach; (e) identify whether the lesion is anterograde or retrograde; (f) identify whether the aortic valve orifice is incomplete, (g) confirm the degree and mechanism of incomplete closure; (h) identify whether there are cumulative branches and the degree of cumulative lesions. There are various AAS complicated with CAD, which results in the difficulty of clinical surgery.…”