Impact of fenestrated stent graft misalignment on patient outcomes

During fenestrated endovascular aneurysm repair (FEVAR), accurate alignment of the fenestration and the target artery is necessary to prevent complications. This study's objective is to determine the incidence of clinical outcomes following fenestration misalignment during FEVAR.

A single-center, retrospective chart review was performed for all elective FEVARs between January 2008 and April 2015. Data were gathered from patient records and intraoperative imaging. Native vessel angles were calculated using the vessel centerlines. Intraoperative stent graft orientation was determined by changing the angle of the image intensifier as the fenestration was profiled for cannulation. Vertical fenestration misalignment was defined as 4 mm or greater and is the distance from the center of the fenestration markers to the center of the target vessel ostium at the time of cannulation. Horizontal stent graft misalignment was defined as a difference between the native vessel angle and the intraoperative fenestration angle of 15° or more. Early and late clinical outcomes were analyzed with respect to the presence of either vertical or horizontal misalignment of the renal artery fenestrations.

The study cohort includes 65 patients who underwent FEVAR during this study period. A horizontal misalignment of 15° or more occurred in 40% of patients (n = 26) and 30° or more in 9.2% of patients (n = 6). A vertical misalignment of 4 mm or greater occurred in 32.3% of patients (n = 21). The incidence of severe postoperative complications, defined as any in-hospital end-organ ischemia and/or death, was significantly greater for patients with stent graft misalignment-31% (n = 11) vs 3% (n = 1) in the aligned group. There was a trend toward higher rates of target vessel cannulation failure in patients with stent graft misalignment 3% (n = 99 fenestrations) vs 0% (n = 76 fenestrations). The combined incidence of any intraoperative target vessel complication was significantly higher in patients with misalignment, 8.1% (4, 15) vs 1.3% (0, 8). Long-term survival was significantly lower in patients with stent graft misalignment, which was primarily driven by high intraoperative and in-hospital mortality rates (P < .05).

Intraoperative stent graft misalignment is associated with higher rates of procedural target vessel complications and severe postoperative adverse events. Patients with stent graft misalignment should be considered at high risk for early postoperative complications. These results highlight an important need for improved FEVAR planning.