Impact of fenestrated stent graft misalignment on patient outcomes.

OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

The in-hospital costs of treating high-risk patients with fenestrated and branched endografts.

OBJECTIVE: This study determined the 30-day morbidity and mortality and in-hospital costs of elective fenestrated (fEVAR) and branched (bEVAR) endovascular aneurysm repairs at a single academic institution and determined factors that influence them. METHODS: All elective fEVAR or bEVAR patients treated between November 2007 and March 2014 in a Canadian academic hospital were included. Procedural details, 30-day morbidity and mortality rates, and cost of hospitalization were analyzed. Nonparametric bootstrap analysis was used to compare means between groups and calculate confidence intervals (CIs). RESULTS: There were 84 consecutive fEVAR (n = 61) and bEVAR (n = 23) procedures. The 30-day mortality was 3.3% for fEVAR and 4.3% for bEVAR. Mean hospital stay was 7.2 ± 0.8 days for fEVAR and 12.6 ± 2.2 days for bEVAR. The mean cost of the index hospitalization was $57,000 for fEVAR and $91,000 for bEVAR. Device-related costs accounted for 55% of the total costs. The occurrence of intraoperative or postoperative events were used to further divide each of the fEVAR and bEVAR groups into "complicated hospitalization" (fEVAR, n = 10; bEVAR, n = 13) and "uncomplicated hospitalization" (fEVAR, n = 51; bEVAR, n = 10) groups. Device-related costs were not significantly different between the complicated and uncomplicated hospitalization groups (mean difference [95% CI] fEVAR: $3383 [-$3405 to $9809], P = .3; and bEVAR: $1930 [-$7892 to $11,288], P = .68). However, there were significant differences between the complicated and uncomplicated hospitalization groups in hospital length of stay (mean difference [95% CI] fEVAR: 8.1 [3.0-13.2] days, P = .001; and bEVAR: 10.8 [5.9-19.9] days, P = .002) and nondevice-related costs (mean difference [95% CI,] fEVAR: $25,843 [$11,689-$43,247], P = .001; and bEVAR; $20,326 [$9362-$36,615], P = .002). CONCLUSIONS: bEVAR and fEVAR are expensive interventions. Intraoperative adverse events and postoperative systemic complications dramatically increase costs and length of stay. Measures to minimize complications will reduce hospitalization costs and improve patient outcomes.

Comparison of Qualitative and Quantitative Assessments of Iliac Artery Tortuosity and Calcification.

INTRODUCTION: During endovascular aneurysm repair, the iliac artery typically serves as a conduit for device delivery. The degree of tortuosity and calcification in the iliac artery ultimately determines whether the device can successfully traverse the vessel. These 2 parameters can be assessed using qualitative approaches or calculated using quantitative methods based on the Society for Vascular Surgery (SVS) reporting standards. The objective of this study was to determine whether qualitative methods are sufficient to accurately assess iliac artery tortuosity and calcification by calculating interobserver variability and comparing them to the SVS Reporting Standards. METHODS: Three vascular surgeons reviewed preoperative computed tomography scans for 50 patients who underwent fenestrated endovascular aneurysm repair and qualitatively assessed left and right iliac artery tortuosity and calcification. Iliac artery geometries were segmented from these image sets. Tortuosity index and calcification length ratio were calculated and categorized based on the SVS Reporting Standards. RESULTS: Interobserver variability was calculated for the qualitative assessments using interclass correlation coefficients. For tortuosity index, among the 3 observers, good agreement was found for the left iliac artery and fair agreement was found for the right. For calcification length ratio, excellent agreement was found for both iliac arteries. When compared to the quantitative assessment, the qualitative assessments underpredicted tortuosity in 2.3% of cases, matched the quantitative values in 16.7% of cases, and overpredicted tortuosity in 81.0% of cases. The qualitative assessments underpredicted calcification in 46.3% of cases, matched the quantitative values in 49.3% of cases, and overpredicted calcification in 4.3% of cases. CONCLUSION: Qualitative assessment of iliac artery tortuosity showed fair-to-good interobserver agreement and poor agreement to SVS Reporting Standards. Qualitative assessment of iliac artery calcification showed excellent interobserver agreement and fair agreement to SVS Reporting Standards. These trends should be considered when qualitative reporting methodologies are used.

Analysis of Iliac Artery Geometric Properties in Fenestrated Aortic Stent Graft Rotation.

INTRODUCTION: A complication of fenestrated endovascular aneurysm repair is the potential for stent graft rotation during deployment causing fenestration misalignment and branch artery occlusion. The objective of this study is to demonstrate that this rotation is caused by a buildup of rotational energy as the device is delivered through the iliac arteries and to quantify iliac artery geometric properties associated with device rotation. METHODS: A retrospective clinical study was undertaken in which iliac artery geometric properties were assessed from preoperative imaging for 42 cases divided into 2 groups: 27 in the nonrotation group and 15 in the rotation group. Preoperative computed tomography scans were segmented, and the iliac artery centerlines were determined. Iliac artery tortuosity, curvature, torsion, and diameter were calculated from the centerline and the segmented vessel geometry. RESULTS: The total iliac artery net torsion was found to be higher in the rotation group compared to the nonrotation group (23.5 ± 14.7 vs 14.6 ± 12.8 mm-1; P = .05). No statistically significant differences were found for the mean values of tortuosity, curvature, torsion, or diameter between the 2 groups. CONCLUSION: Stent graft rotation occurred in 36% of the cases considered in this study. Cases with high iliac artery total net torsion were found to be more likely to have stent graft rotation upon deployment. This retrospective study provides a framework for prospectively studying the influence of iliac artery geometric properties on fenestrated stent graft rotation.

Symptomatic congenital saccular aneurysm of the inferior vena cava associated with a circumaortic left renal vein.

Congenital saccular aneurysms of the inferior vena cava (IVC) are extremely rare, with 23 cases reported so far. We present a case of a 55-year-old woman with an acute episode of back pain that mimicked aortic dissection. Computed tomography ruled out aortic dissection but demonstrated a saccular aneurysm of the infrarenal IVC and a circumaortic left renal vein. The saccular aneurysm was excised, and the postoperative anatomopathologic examination revealed that it was congenital in nature. Surprisingly, preoperative symptoms of recurrent palpitations, dyspnea, and positional abdominal discomfort resolved after resection. This is the first reported case of a symptomatic congenital saccular aneurysm of the IVC with an associated circumaortic left renal vein.