Abstract
OBJECTIVE: Both standard and low-profile endografts have been used for physician-modified endografts (PMEGs) to treat complex aortic aneurysms; however, recent data from a 2025 multi-institutional analysis suggest that low-profile devices are associated with type IIIc endoleak rates as high as 15% at the 20-month follow-up. Early demonstrations of PMEG modifications, including fenestration reinforcement with polytetrafluoroethylene (PTFE) cuffs, have proposed a possible remedy to these elevated endoleak rates. This analysis evaluates a single center's experience with PTFE cuff reinforcement for PMEG fenestrations.
METHODS: All PMEGs performed at our institution between 2016 and 2025 were retrospectively reviewed. Each PMEG included fenestrations that were individually reinforced with a PTFE cuff and an embolization coil, secured with a running locking Ethibond suture. Primary outcomes included target vessel-related (type Ic and IIIc) endoleaks and endoleak-related reintervention. Outcomes were analyzed on both per-patient and per-fenestration bases. Bridging stent type (iCAST vs VBX) was also evaluated as a potential modifier of outcomes, with secondary outcomes including stent patency and target vessel instability. Rates of endoleak at 1 month and beyond were reported using Kaplan-Meier estimates.
RESULTS: Overall, 229 PMEGs (100% low profile; 861 PTFE cuffs) were included in our analysis with a median follow-up of 1.3 years. The median age was 76 years and patients were primarily White (89%) and male (72%). The majority of cases were done electively (82%) for juxtarenal aneurysms (65%). The median aneurysm diameter at time of repair was 62 mm, and 80% included four or more target vessel fenestrations. Through 2 years, 26% (n = 42) of patients underwent an aneurysm- or PMEG-associated reintervention; of these, nearly one-half (n = 21 [15% of all patients]) were endoleak related. The most common indication for endoleak-related reintervention was sac expansion from type II endoleaks (8.9%). Type Ic and IIIc endoleaks occurred in 2.2% and 1.1% of patients, respectively. Bridging stents included 358 iCAST and 489 VBX. Stent distribution differed significantly by vessel, yet no significant differences were observed in 2-year patency (98% vs 99%), stent-related stenosis/occlusion (2.1% vs 2.0%), or reintervention rates (1.0% vs 1.3%) (all P > .05). On a per-fenestration basis, type Ic and IIIc endoleaks occurred in 0.6% and 0.1% of fenestrations, respectively, with no difference based on stent type (iCAST, 0.7% vs VBX, 0.8%; P = .23). Overall, freedom from target vessel instability at 2 years was >98% across all groups and vessels, without any difference in bridging stent type (98.3% vs 98.6%; P = .82).
CONCLUSIONS: PMEG modification with individual fenestration reinforcement using a PTFE cuff and an embolization coil demonstrates effective fenestration sealing with notably low rates of target vessel-related endoleaks. Bridging stent choice does not appear to be a primary determinant of target vessel instability, endoleaks, or reinterventions, potentially underscoring the importance of fenestration modifications over stent platform differences. These findings suggest the value of using this technique for PMEG customization in low-profile devices.