Evolution of practice patterns and learning curve of aortic repair using the E-nside off-the-shelf inner branch...

To report the impact of the learning curve on the outcomes of branched endovascular aortic repair using an off-the-shelf preloaded inner branch device (E-nside).

Data from a physician-initiated national multicenter registry, including patients treated with E-nside endograft (INBREED [ItaliaN Branch Registry of E-nside EnDograft]) were collected prospectively (2020-2024). End points were early (30-day) technical success, mortality, major adverse events (MAEs), and 2-year freedom from endograft instability and target vessel instability. Patients were divided into early and late cohorts based on the median date of the procedure in each center.

There were 215 patients treated with the E-nside, 108 (393 target vessels) in the early and 107 (395 target vessels) in the late cohort. Most patients had a degenerative aneurysm (early, 82%; late, 75%; P = .326) or a chronic dissection (early, 6%; late, 15%; P = .025). Aneurysm extent was thoracoabdominal in 53% of patients and complex abdominal in 47%; and 23% were ruptured or symptomatic and 26% had an aneurysm size of more than 70 mm, without differences between groups. A narrow paravisceral aortic lumen of less than 25 mm was more frequent in the late cohort (late, 30%; early, 18%; P = .037). From the early to the late groups, there was an increase in the use of a total transfemoral approach (late, 29% vs early, 18%; P = .042), balloon-expandable bridging stents (late, 82% vs early, 76%; P = .032), and reinforcement bridging stents (late, 26%; early, 11%; P < .001). Operating time (late, 267 ± 131 minutes; early, 244 ± 130 minutes; P = .230), iodinated contrast volume (late, 181 ± 81 mL; early, 210 ± 141 mL; P = 108; P = .302), and dose area product (late, 272 ± 110 Gycm² early, 291 ± 118 Gycm²; P = .277) were similar in the two groups. Intraprocedural complications decreased in the later stage of the learning curve (late, 11%; early, 23%; P = .030), whereas overall 30-day mortality (late, 8%; early, 6%; P = .346), technical success (late, 99%; early, 98%; P = .286), and MAEs (late, 27%; early, 29%; P = .879) remained substantially stable. There were no differences in 2-year freedom from endograft instability (late, 100 ± 0%; early, 96 ± 5%; P = 1.00), freedom from target vessel instability (late, 98 ± 3%; early, 94 ± 2%; P = .090), and target vessel primary patency (late, 97 ± 2%; early, 97 ± 2%; P = .321).

The increased experience with the E-nside endograft was associated with a more frequent use of a total transfemoral approach and use of balloon-expandable and reinforced bridging stents. From the early to the late stages, there was a significant decrease in intraoperative complications, although most centers were learning independent and achieved a consistent mortality, MAE, procedural metrics, and mid-term results from the start.