Four-dimensional computed tomography assessment of ruptured triple lumen type B aortic dissection: A case report

Abstract

Abstract Background Few studies have investigated the effect of the intimal morphology of type B aortic dissection(TBAD) on the blood flow after rupture. We report a case of a 30-yar-old male with complicated TBAD, who underwent assessment with four-dimensional computed tomography (4D-CT). Case Summary Patient presented with chest tightness for 14 days, a heart rate of 67 bpm, regular rhythm, and two years of hypertension. Precisely 14 days prior, he had been diagnosed with aortic dissection by ultrasound at another hospital. 4D-CT showed thoracoabdominal aortic dissection (Stanford type B), left haemothorax, multiple dissection tears, an initial tear located at the large curvature side of the aortic arch, a proximal tear entrance >15 mm, and a descending aorta exit >5 mm. 4D-CT analysis and visualisation of the intimal flap showed a parallel three-lumen spatial morphology of true-false-true, and the lumen showed partial thrombosis in the false lumen. Further quantitative analysis of the area of the initial and re-entry tear during the cardiac cycle revealed that the ratio of the initial tear to re-entry tear was consistent with the expansion ratio of the false lumen to the true lumen of the re-entry tear. The patient improved and was discharged one week after undergoing TEVAR for descending aortic dissection. Discussion The complex triple-lumen TBAD, characterized by multiple tears and blood flow channels, poses challenges for thoracic endovascular aortic repair (TEVAR). 4D-CT facilitates the visualization of intimal flap spatial distribution and enables a thorough assessment of interlayer dilation risk within a realistic and complex haemodynamic context, thereby refining the risk stratification for the progression of complicated aortic dissection and its associated complex complications.