Concomitant Endografting of a?Type B Aortic Dissection During Transfemoral Aortic Valve Replacement

摘要

An 87-year-old woman with severe aortic stenosis underwent a transfemoral transcatheter aortic valve replacement (TAVR). Intraoperative transesophageal echocardiography demonstrated a well-seated valve with no paravalvular leak; however, a new acute type B aortic dissection was identified. Endografts were delivered through the TAVR sheath and deployed, effectively treating the dissection. The patient did well postoperatively, with imaging at 2 years demonstrating a well-functioning aortic valve and no migration or endoleak of the thoracic endografts. To our knowledge, this is the first report of successful concomitant thoracic endografting during TAVR for the treatment of iatrogenic aortic dissection in this setting.;;Dr Szeto discloses a financial relationship with Edwards Lifesciences, Medtronic, LivaNova, and Micro?Interventional Devices; Dr Bavaria with Edwards Lifesciences, Medtronic, COOK Medical, Boston Scientific, W. L. Gore and Associates, and St Jude Medical; Dr Anwaruddin with Edwards Lifesciences and Medtronic; Dr Desai with Medtronic and W. L. Gore and Associates.;To our knowledge, this is the first report of concomitant TEVAR for the treatment of an iatrogenic acute type B aortic dissection during transfemoral TAVR. Preoperative imaging can identify patients at high risk for this complication based on anatomic factors including degree of calcification and tortuosity of the aorta. In this particular case, there was severe calcification and angulation of the distal aortic arch. It is likely that the TAVR valve, during arch transit, caused lifting of a calcific plaque, leading to flow between the plaque and the adventitial layer that progressed antegrade into a true Debakey IIIa dissection.Acute uncomplicated type B dissections have classically been managed with medical therapy. Proponents of the medical therapy strategy have pointed to a lack of firm data establishing a survival benefit to TEVAR in this clinical setting. In addition, there are operative risks associated with TEVAR, including a risk of retrograde type A dissection.We advocate for TEVAR in this scenario because of several factors. The risk of mortality is significantly increased in iatrogenic versus spontaneous type B dissections (37% versus 10%) [3][3]. In the setting of TAVR, the first report of an iatrogenic type B dissection was unrecognized and resulted in rupture and death [4][4]. Presumably, the depth of injury in these cases extends further into the aortic wall than traditional type B dissection, which begins with a primary intimal tear. From a technical standpoint, the endografts can be delivered through the existing TAVR access and wires. Particular attention should be paid to not oversizing the endografts more than 10% to mitigate the risk of retrograde dissection. For this reason, it is our practice to oversize grafts by 10% and to avoid ballooning in aortic dissections. In this case, we used traditional sizing measurements based on preoperative computed tomography to size the endograft. We typically use preoperative spinal drains in all patients considered high risk for spinal ischemia, although no drain was placed in this case because it was an unplanned urgent procedure. Our protocol for postoperative spinal cord ischemia is spinal drainage to a cerebrospinal fluid pressure less than 10 cm H20 and maintaining mean arterial pressures greater than 90 mm Hg.In the longer term, randomized trial data from the ADSORB and INSTEAD clinical trials have demonstrated significant improvements in aortic remodeling in patients treated with TEVAR for acute uncomplicated type B dissections, with higher rates of complete false lumen thrombosis and greater reduction of false lumen diameter compared with medical therapy alone [5, 6]. In conclusion, we demonstrate the first case of concomitant TEVAR for iatrogenic acute type B dissection during transfemoral TAVR and advocate for its use in this setting because of technical ease, the reduction in associate