CT Imaging Of Type B Aortic Dissection Endovascular Repair Postoperative Follow-up:What Factors Are Associated With The Change Of The False Lumen

Backgroud:Endovascular aortic repair is one of the most important therapy for acute type B aortic dissection, but the persistence of false lumen after repair process interferes with the therapeutic effect. False lumen diameter expanding can forecast complications and death associated with aorta.Purpose;To investigate the factors that be associated with variation of lumen diameter by using computed tomography, which consisting of the postoperative residual numbers of entry tears, the location of the top residual tear entry and the affected situation of main branches of aorta.Material and method:Collecting the patients clinically diagnosed with type B aortic dissection, all of which were treated with endovascular aortic repair and adopted aortic CT examination at least more than2times after intervention. Two radiologists measured the false lumen and main diameter on CTA images respectively and calculated the diameter changes in value every year. Observated the postoperative residual numbers of entry tears, the location of the top residual tear entry and the main aorta branches, then analyzes the relations between these factors and aortic diameter changes. We suggested p<0.05for difference was statistically significant.Result:Altogether of49patients,39male and10female, measured a total of147segments. The average variations of the false lumens diameter respectively were:-0.65±2.73,0.91±3.6,0.41±2.9, and the whole false lumen diameter variation was0.24±2.74. The average variations of the main lumens respectively were:0.51+2.32,0.98±2.98,0.57±2.14, and the whole main lumen variation was0.69±1.72. The units were mm/year. The postoperative residual numbers of entry tears, the location of the top residual tear entry were correlated with false lumen diameter changes (p<0.05). At celiac axis and renal artery levels, the more entry tears, the faster lumen expanded, and the false lumens without obvious tear became closure or smaller. The variation of false lumen at celiac axis level and the variation of total lumen at renal artery were associated with the location of the top residual tear entry(p=0.048;0.002). There was no correlation between false lumen diameter variation and the factors of patients’gender, age, smoking, hypertension and the extent of aortic atherosclerosis.Conclusion:The number of entry tears and main aorta branches involved were the main predictors of false lumen expanding. It may provide guideline for monitoring these patients closely, or adopting intervention as soon as possible.