Stent-induced new entry and device migration associated with hemodynamic stress after thoracic endovascular aortic repair for type B chronic aortic dissection using computational fluid dynamics analysis: a case report

Abstract

BackgroundStent graft-induced new entry (SINE) after thoracic endovascular aortic repair (TEVAR) is a serious adverse event which leads to stent graft migration and rupture. SINE is known to be more frequent in cases of chronic dissection and oversizing. However, few studies have evaluated the influence of hemodynamic stress on SINE in patients with chronic dissection. Here, we report a rare case of TEVAR for chronic dissection with a dissection stent, inducing SINE 6 years after the first surgery. In addition, we analyze the hemodynamic stress for the aortic event using computational fluid dynamics (CFD) analysis.Case presentationA 69-year-old male underwent TEVAR with left subclavian artery debranching for chronic type B aortic dissection, using a stent graft and dissection stent. The postoperative course was uneventful, but follow-up computed tomography (CT) showed that the stent graft and bare-metal stent had dislodged 4 years after surgery. The gap between the bare-metal stent and the stent graft increased over time, and the proximal edge of the bare-metal stent led to SINE at the descending aorta 6 years after surgery. We performed reintervention to cover the SINE. The patient recovered well and was discharged at 6 days postoperatively. He is currently in good condition 6 months after reintervention. CFD analysis of the patient’s CT image suggested that the local change in wall shear stress at the stent graft and dissection stent might be related to the aortic event.ConclusionHemodynamic stress is a factor affecting SINE and device migration. CFD may be useful for evaluating patient-specific risk of aortic events.