Impact of True and False Lumen Origins on Target Vessel Instability in Post-Dissection F/BEVAR

To evaluate the occurrence of target artery-related adverse events in post-dissection F/BEVAR patients, based upon artery origin from the true or false lumen. This is a multicenter, prospective, cohort study evaluating post-dissection patients treated with F/BEVAR, in the US Aortic Research Consortium. The primary endpoint was 5-year target vessel instability (TVI). Secondary endpoints included 5-year primary patency, freedom from secondary interventions (SIs), and type Ic and IIIc endoleaks. The analysis was performed on a per-vessel basis. A total of 1052 target arteries were analyzed, primarily including the celiac, superior mesenteric, and renal arteries, with individual hepatic and splenic arteries occasionally incorporated in the repair. Of the 277 patients included, 75% were men, and 19% were black, with a mean age of 66.8 ± 10.3 years. The mean aneurysm sac diameter was 66.0 ± 11.4 mm, with extent II thoracoabdominal aneurysms being the most prevalent (72.6%) among this cohort. Technical success was obtained in 96% of the cases. As primary outcome, the incidence of target vessel instability (TVI) was significantly lower (P<0.001) among the true-lumen vessels (16.4%) compared to false-lumen (29.9%) and dual-lumen arteries (43.8%). As for the secondary outcomes, the incidence of type Ic endoleak was significantly higher (P=0.001) in false-lumen vessels (9.6%) and dual-lumen vessels (8.6%) compared to true-lumen vessels (3.3%). There was no significant difference in the incidence of type IIIc endoleak (p=0.241) or target vessel occlusion (P=0.458). Target artery stenosis was significantly more common among arteries originating from the false lumen compared to true lumen (2.6% vs 0.4%, P=0.009). Fenestrations were associated with a higher incidence (30.5%) of TVI when compared to branches (5.9% P=0.005), however, this was observed only among dual-lumen vessels. Arteries incorporated by a fenestration and that had a dual-lumen origin, were associated with a higher occurrence of secondary interventions (23.7%) compared to true-lumen vessels (8.6%, P=0.010). The same was not observed among the arteries incorporated by a branch configuration. The time-to-event analysis demonstrated a significantly higher 5-year freedom from TVI in true-lumen vessels compared to false and dual-lumen ones (True lumen: 83.6%; False=70.1 %; Dual=56.2 %; Log-rank P=0.0002). Freedom from secondary interventions at 5 years was significantly higher in true-lumen vessels compared to dual-lumen ones (Log-rank P=0.0104), but not to false-lumen arteries (Log-rank P=0.0847). The 5-year primary patency did not differ significantly among groups (True lumen: 98.3%; False = 92.6%; Dual=93.9%; Log-rank P=0.1368). On Cox proportional hazards analysis, dual-lumen (95% CI 1.24-3.28, p=0.005) and false-lumen (95% CI 1.04 - 2.60, p=0.0325) target arteries were associated with an increased hazard of TVI, when compared to true lumen arteries, having 2.02 (P=0.005) and 1.65 (P=0.0325) times more risk of presenting TVI than a true-lumen vessel CONCLUSIONS: In F/BEVAR for post-dissection aneurysms, target vessel instability and secondary intervention are significantly lower in target arteries originating from the true lumen, when compared to false-lumen or dual-lumen vessels. Device design, with use of fenestrations or branches may also play a role, with a significant difference only observed in dual-lumen target arteries.