First-in-man results of a novel vascular graft coated with resorbable polymer for aortic reconstructions--a multicenter, non-randomized safety study.

Objectives: The purpose of this "first-in-man" study was to investigate the safety of a novel vascular polyester prosthesis coated with a resorbable polymer and free of any animal-based coating agents such as gelatin or collagen.

Methods: In a nonrandomized first-in-man multicenter safety study, the frequency of perigraft seroma (PGS) as the primary endpoint was studied in consecutive patients undergoing aortic reconstructions. The follow-up control to study the primary endpoint was intended at 3 months under routine clinical conditions. Pre- and postoperative white blood cell counts (WBC), C-reactive protein (CRP), and liver enzyme levels to characterize the systemic inflammation response and possible metabolic consequences were determined at different postoperative time points (secondary endpoints). Additionally, the primary unassisted patency rate, perioperative complications and serious adverse events, as well as intraoperative handling properties of the graft based on a semiquantitative scale were assessed. Magnetic resonance angiography (MRA) follow-up investigations were scheduled postoperatively at 3 months to determine graft tissue integration and the presence of PGS.

Results: A total of 24 patients with comorbidities such as coronary artery disease (8.3 %, 2/24), chronic occlusive pulmonary disease (COPD, 8.3 %, 2/24), Fontaine III/IV (20.8 %, 5/24), and diabetes (20.8 %, 5/24) were enrolled from June 2011 to September 2012. Due to two early nongraft-related deaths, there were 22 patients that had a follow-up. In these 22 patients, the freedom from PGS was 90.9 % (20/22) suggesting that the graft/tissue integration was comparable to other vascular grafts described in the relevant literature. WBC counts were not significantly different (pre (8.67 ± 2.98 1/nl) vs. follow-up (7.97 ± 2.24 1/nlI, p = 0.203). Likewise, preoperative CRP serum levels (6.47 ± 11.59 mg/l) were not different from those at follow-up (7.87 ± 12.81 mg/l, p = 0.769). There were two patients with a documented coagulation disorder and two premature deaths (cardiac failure, cerebral bleeding). The primary unassisted patency at follow-up was 77.3 % (17/22) in all patients who reached the follow-up (85.0 % or 17/20 if two cases with documented coagulation disorders are excluded). The reasons for occlusions were technical/surgical difficulties (2/5) and documented coagulation disorders (2/5). In one occlusion, the cause was unknown. There were no graft infections. Intraoperative graft handling properties were evaluated less favorable as compared to the routinely used gelatin- or collagen-coated polyester grafts in each investigator's clinical practice.

Conclusions: Our results suggest that Uni-Graft® Synthetic is a promising prosthetic vascular graft to reduce PGS. Our findings should be interpreted with caution noting the limitation of the lack of a control group.