Volume analysis of true and false lumens in acute complicated type B aortic dissections after thoracic endovascular aortic repair with stent grafts alone or with a composite device design.

OBJECTIVE: This study compared the 12-month evolution of the aortic volume in patients who underwent thoracic endovascular aortic repair (TEVAR) with stent grafts alone or a composite device (Zenith TX2 stent graft and Zenith Dissection stent; Cook Medical, Bloomington, Ind) for acute (≤2 weeks from onset) complicated type B aortic dissection. METHODS: This was a retrospective analysis comparing prospectively collected data from 45 patients who underwent standard TEVAR repair at three European institutions (TEVAR group) and 39 patients in the Study of Thoracic Aortic type B Dissection using Endoluminal Repair (STABLE I) study who received a composite device (STABLE group). The analysis included consecutive patients treated for acute, complicated type B dissection and with available baseline and 12-month computed tomography imaging. Volume analysis was performed by using a semiautomated centerline algorithm. RESULTS: Baseline demographics, medical history, extent of dissection, and clinical indications were largely similar between the two groups. There was no difference in the length of aorta covered by stent grafts (167 ± 47 mm in STABLE and 184 ± 49 mm in TEVAR; P = .11). The STABLE group had an initial larger false lumen volume in the thoracic (203 ± 72 cm(3) vs 162 ± 74 cm(3); P = .01) and abdominal aorta (63 ± 29 cm(3) vs 36 ± 27 cm(3); P < .001). In the thoracic aorta, each group exhibited a significant increase in true lumen volume and a significant decrease in false lumen volume through 12 months. The total aortic volume increased significantly in the STABLE group (P < .001) but not in the TEVAR group. In the abdominal aorta, only the STABLE group exhibited a significant increase in the true lumen volume (P < .001) and a significant decrease in the false lumen volume (P = .004) postoperatively. At 12 months, the true lumen continued to increase significantly in the STABLE group (P = .03). However, no statistically significant difference was detected when the two groups were compared for the overall changes in the true lumen and false lumen volumes from preprocedure to 12 months, and both groups exhibited a statistically significant increase in total abdominal aortic volume at 12 months. There was no statistical difference between the two groups in the proportions of patients who experienced >10% changes in the thoracic or abdominal total lumen volume after TEVAR. Patients in the two groups (all survived 12 months) had similar clinical outcomes, including rupture, conversion, and reinterventions. CONCLUSIONS: According to this volume analysis, thoracic endografting for acute complicated type B dissections promotes significant thoracic aortic remodeling. The use of bare-metal dissection stents leads to significant true lumen expansion and false lumen regression in the early follow-up and to subsequent continued true lumen expansion in the abdominal aorta; however, a definitive benefit in aortic remodeling over TEVAR alone was not demonstrated at 1 year.

Aortic remodeling after endovascular treatment of complicated type B aortic dissection with the use of a composite device design.

OBJECTIVE: The purpose of this study is to report updated clinical and aortic remodeling results from the Study for the Treatment of complicated Type B Aortic Dissection using Endoluminal repair (STABLE) trial, a prospective, multicenter study evaluating safety and effectiveness of a pathology-specific endovascular system (proximal stent graft and distal bare metal stent) for the treatment of complicated type B aortic dissection. METHODS: All 86 enrolled patients (mean age, 59 years; 73.3% men) were treated within 90 days of symptom onset (55 with acute dissections and 31 with nonacute dissections). Inclusion criteria were branch vessel obstruction/compromise, impending rupture as evidenced by periaortic effusion/hematoma, resistant hypertension, persistent pain/symptoms, or aortic growth ≥5 mm within 3 months (or transaortic diameter ≥40 mm). Remodeling of the dissected aorta, including thrombosis of the false lumen and changes in the true lumen, false lumen, and transaortic diameter, were assessed in patients with available computed tomographic imaging through 2 years. RESULTS: The 30-day mortality rate was 4.7% (4/86) in the overall patient group (5.5% in acute patients and 3.2% in non-acute patients). Freedom from all-cause mortality was 88.3% at 1 year and 84.7% at 2 years (no significant difference between acute and nonacute patients). From baseline to 2 years, the true lumen diameter increased significantly in the descending thoracic aorta and the more distal abdominal aorta, along with a decrease in the false lumen diameter in both aortic segments. A majority of patients had either a stable or shrinking transaortic diameter in the thoracic (80.3% at 1 year and 73.9% at 2 years) or abdominal aorta (79.1% at 1 year and 66.7% at 2 years). Transaortic growth (>5 mm) occurred predominantly in acute dissections. Consistently, a shorter time from symptom onset to treatment was found to predict transaortic growth in the abdominal aorta (P = .03). CONCLUSIONS: Endovascular repair of complicated type B aortic dissection with the use of a composite construct demonstrates favorable early clinical outcomes and aortic remodeling. However, patients treated in the acute setting may be prone to aortic growth and may require close observation. Follow-up through 5 years is ongoing.

Results of the United States multicenter prospective study evaluating the Zenith fenestrated endovascular graft for treatment of juxtarenal abdominal aortic aneurysms.

OBJECTIVE: This study reports the results of a prospective, multicenter trial designed to evaluate the safety and effectiveness of the Zenith fenestrated endovascular graft (Cook Medical, Bloomington, Ind) for treatment of juxtarenal abdominal aortic aneurysms (AAAs). METHODS: Sixty-seven patients with juxtarenal AAAs were prospectively enrolled in 14 centers in the United States from 2005 to 2012. Custom-made fenestrated stent grafts were designed with one to three fenestrations on the basis of analysis of computed tomography data sets. Renal alignment was performed with balloon-expandable stents. Follow-up included clinical examination, laboratory studies, mesenteric-renal duplex ultrasound, abdominal radiography, and computed tomography imaging at hospital discharge and at 1 month, 6 months, and 12 months and yearly thereafter up to 5 years. RESULTS: There were 54 male and 13 female patients with a mean age of 74 ± 8 years enrolled. Mean aneurysm diameter was 60 ± 10 mm. A total of 178 visceral arteries required incorporation with small fenestrations in 118, scallops in 51, and large fenestrations in nine. Of these, all 118 small fenestrations (100%), eight of the scallops (16%), and one of the large fenestrations (11%) were aligned by stents. Technical success was 100%. There was one postoperative death within 30 days (1.5%). Mean length of hospital stay was 3.3 ± 2.1 days. No aneurysm ruptures or conversions were noted during a mean follow-up of 37 ± 17 months (range, 3-65 months). Two patients (3%) had migration ≥ 10 mm with no endoleak, both due to cranial progression of aortic disease. Of a total of 129 renal arteries targeted by a fenestration, there were four (3%) renal artery occlusions and 12 (9%) stenoses. Fifteen patients (22%) required secondary interventions for renal artery stenosis/occlusion in 11 patients, type II endoleak in three patients, and type I endoleak in one patient. At 5 years, patient survival was 91% ± 4%, and freedom from major adverse events was 79% ± 6%; primary and secondary patency of targeted renal arteries was 81% ± 5% and 97% ± 2%, freedom from renal function deterioration was 91% ± 5%, and freedom from secondary interventions was 63% ± 9%. CONCLUSIONS: This prospective study demonstrates that endovascular repair of juxtarenal AAAs with the Zenith fenestrated AAA stent graft is safe and effective. Mortality and morbidity are low in properly selected patients treated in centers with experience in these procedures.