Experience of the Zenith Dissection Endovascular System in the emergency setting of malperfusion in acute type B dissections

Objective: This study evaluated the safety and effectiveness of the Zenith Dissection Endovascular System (Cook Medical, Bloomington, Ind) in the urgent treatment of acute type B aortic dissections complicated by organ malperfusion. Methods: Between June 2011 and June 2013, we prospectively enrolled all patients with acute type B dissection (<14 days) complicated by visceral malperfusion and treated by the Zenith Dissection Endovascular System, including a proximal covered stent and a distal noncovered stent. Organ malperfusion was diagnosed during the clinical, biological, and morphologic follow-up of patients admitted to a dedicated intensive care unit (SOS Aorta). End points were 30-day mortality and morbidity, and reoperation rate, survival, and remodelling of the dissected aorta during follow-up. Results: Fifteen patients (11 men; mean age, 60 +/- 12 years) were treated in emergency procedures with a median delay of 36 hours. Malperfusions included renal ischemia in all patients, intestinal ischemia in nine, and lower limb ischemia in six. The proximal entry tear in each patient was covered by a stent Zenith TX2 graft (mean diameter, 36 mm; mean length, 170 mm; Cook Medical), supplemented by a noncovered aortic stent (diameter, 36 or 46 mm; length, 164 mm) with a technical success rate of 100%. The left subclavian artery in 10 patients was covered without revascularization. One chimney was necessary to revascularize the left common carotid artery. Six patients required complementary arterial branch stenting for persistent static malperfusion, using eight peripheral stents (five iliacs, three renals). No deaths were recorded during the 30-day postoperative period. Major adverse events were reported in three patients (20%): 1 paraparesis with complete recovery, 1 colonic resection, 1 stroke, and 2 transient renal failures. The mean hospital stay was 14 +/- 6 days. During a mean follow-up of 8 +/- 3 months, one sudden death, no aortic-related complications, and no reoperations or conversions were recorded. Remodelling with healing of the thoracic false lumen was obtained in 10 patients (67%), and five others had a partially thrombosed false lumen without remodelling. Conclusions: Used as a treatment for organ malperfusion complicating acute type B dissections, the Zenith Dissection Endovascular System achieved safely and effectively satisfactory clinical results in the short term. The long-term effect of this composite treatment on aortic remodelling remains to be determined.