Analysis of the Learning Curve and Patient Outcomes of Endovascular Repair of Thoracoabdominal Aortic Aneurysms Using Fenestrated and Branched Stent Grafts: Prospective, Nonrandomized, Single-center Physician-sponsored Investigational Device Exemption Clinical Study.

Abstract

To evaluate the outcomes and learning curve of fenestrated and branched endovascular repair (F/BEVAR) of thoracoabdominal aneurysms. Endovascular aneurysm repair has reduced morbidity and mortality compared with open surgical repair. However, application to thoracoabdominal aneurysm repair remains limited by procedural complexity and device availability. Fifty patients treated in a prospective, nonrandomized, single-center Investigational Device Exemption (IDE) study between January 2014 and July 2017 were analyzed. Patients (mean age 75.6 ± 7.5 years; mean aneurysm diameter 67.3 ± 9.8 mm) underwent F/BEVAR of thoracoabdominal aneurysms (58% type IV; 42% type I-III) using custom-manufactured endografts. The experience was divided into 3 cohorts (Early: 1 to 17; Mid: 18 to 34; Late: 35 to 50) to evaluate learning curve effects on key process measures. F/BEVAR included 194 visceral arteries (average 3.9 per patient). Technical success was 99.5% (193/194 targeted arteries). Thirty-day major adverse events (MAEs) included 3 (6%) deaths, 1 (2%) new-onset dialysis, 3 (6%) paraparesis/paraplegia, and 2 (4%) strokes. One-year survival was 79 ± 7%. Comparing the Early and Late groups revealed reductions in procedure time (452 ± 74 vs 362 ± 53 minutes; P = 0.0001), fluoroscopy time (130 ± 40 vs 99 ± 27 minutes; P = 0.016), contrast administration (157 ± 73 vs 108 ± 38 mL; P = 0.028), and estimated blood loss (EBL; 1003 ± 933 vs 481 ± 317 mL; P = 0.042). Intensive care unit (ICU) and total length of stay (LOS) decreased from 4 ± 3 to 2 ± 1 days and from 7 ± 6 to 5 ± 2 days, respectively, but was not statistically significant. Use of F/BEVAR for treatment of thoracoabdominal aneurysms is safe and effective. During this early experience, there was a significant improvement in key process measures reflecting improvements in technique and physician learning over time.