RESUMO
Background: For complicated Stanford type B aortic dissection (TBAD), thoracic endovascular aortic repair (TEVAR) is the recommended treatment; however, the type of renal artery that should be repaired remains controversial. The study aimed to investigate the changes in the renal artery and renal volume in complicated TBAD after TEVAR and the predictors of renal atrophy. Methods: The cohort study retrospectively enrolled patients with acute and subacute complicated TBAD who underwent aortic computed tomography angiography (CTA) 1 month before as well as 1 week and half a year after TEVAR from January 2010 to May 2017. According to the source of blood supply shown in preoperative CT, the renal artery was classified in 3 ways: type 1, supplied by the aortic true lumen; type 2, supplied by the aortic false lumen; or type 3, supplied by both the true and false lumen. Results: A total of 91 patients (81 men and 10 women) with an average age of 48.12±10.35 years were enrolled. Renal arteries were classified as type 1 (n=91), type 2 (n=35), and type 3 (n=56). There was no difference in the distribution of the 3 types on the left and right sides (type 1 vs. type 2 vs. type 3: 52:39 vs. 15:20 vs. 24:32; P=0.152). After TEVAR, type 3 was more likely to have spontaneous healing than type 2 (16.1% vs. 2.9%; P=0.049). There was no significant difference in the preoperative volume of kidneys of the 3 types (type 1 vs. type 2 vs. type 3: 198.23±38.68 vs. 197.37±41.77 vs. 195.10±36.11 mL; P=0.893). The postoperative volume of types 2 and 3 was smaller than that of type 1 (type 1 vs. type 2 vs. type 3: 190.09±43.25 vs. 165.15±52.63 vs. 170.70±45.28 mL; P=0.006). The renal volume was reduced in all 3 types of renal artery, especially in type 2 (the change of renal volume for type 1 vs. type 2 vs. type 3: -8.14±29.31 vs. -32.22±41.59 vs. -24.41±38.44 mL; P=0.001). The relative change of renal volume for type 1 vs. type 2 vs. type 3: (-3.64±15.69)% vs. (-16.00±21.29)% vs. (-11.97±18.22)%; P=0.001). During the median follow-up of 668 days, 7 patients (7.7%) belonging to types 2 and 3 developed renal atrophy. False lumen thrombosis in the abdominal aorta and/or the renal artery was the predictor of renal atrophy [hazard ratio (HR) =17.757; P=0.008]. Conclusions: Patients with type 2 or 3 renal artery and false lumen thrombosis in the abdominal aorta and/or renal artery should be monitored closely and actively intervened to prevent renal atrophy.
RESUMO
Background: The napkin-ring sign (NRS) was accepted as unstable plaques at coronary computed tomography angiography (CCTA). However, the incidence is relatively low. We sought to assess whether the newly defined diamond-attenuation-sign [DAS, defined as a qualitative plaque feature in a mixed plaque (MP) on CCTA cross-section images by the presence of two features: a visual calcification (in the shape of a diamond) accompanied by an annular-shape lower attenuation plaque tissue surrounding the lumen like a ring], could be accurately identified as unstable atherosclerotic plaques. Methods: Eight heart transplant recipients (8 male; mean age, 48.5±11.6 years; range, 37-65 years) underwent CCTA exams prior to heart transplant surgery. Segment-based CCTA sections were independently evaluated for various plaque patterns including non-calcified plaque (NCP) with NRS (NCP-NRS), NCP without NRS (NCP-non-NRS), MP with DAS (MP-DAS), MP without DAS sign (MP-non-DAS), and calcified plaque (CP). Results: NCP-NRS plaques in 6.4% (23/358), NCP-non-NRS plaques in 24.0% (86/358), MP-DAS plaques in 18.2% (65/358), MP-non-DAS plaques in 20.1% (72/358), and calcified-plaques in 7.0% (25/358) of all cases. The specificity and positive predictive values of the MP-DAS and NCP-NRS signs to identify unstable plaque features were excellent (97.1% vs. 98.6%, 90.8% vs. 87.0%, respectively). DAS plaques were more frequently seen on CCTA exams than that of NRS (39.3% vs. 13.3%, respectively, P=0.001). The diagnostic performance of MP-DAS to identify unstable coronary lesions was superior compared to NCP-NRS [area under the receiver operating characteristic curve (ROC), 0.756; 95% CI: 0.717-0.791 vs. 0.558; 95% CI: 0.514-0.600, respectively, P<0.001]. Conclusions: Both the DAS and NRS had a high specificity and positive predictive value for the presence of unstable lesions. DAS was a better identification of unstable atherosclerotic plaques in the assessment of plaque-calcification-pattern (PCP).