PC16. No Major Difference in Long-Term Outcomes for EVAR Placed Outside of Instructions for Use (IFU)

Abstract

Studies have shown that the majority of endovascular aneurysm repair (EVAR) is performed outside the instructions for use (IFU). We report our long-term outcomes following EVAR with respect to device-specific IFU. CT angiography data from 566 consecutive patients who underwent elective EVAR between 2003 and 2014 were examined. Preoperative anatomic measurements for each patient were taken and compared with device-specific IFU. Primary outcomes included all-cause mortality and AAA-related mortality. Secondary outcomes were late-onset rupture, need for reintervention, endoleaks, aneurysm sac enlargement, and operative complications. Ten different stent grafts were placed in this set of patients with a mean follow-up of 3.54 ± 2.65 years. Most patients (465 [82.2%]) were male, and the mean age was 74.8 ± 8.70 years. Overall, 176 patients (31.1%) fit all IFU criteria, and 535 patients (94.5%) fit at least half of IFU criteria. Iliac diameter was most commonly outside of IFU (253 [44.7%]). Demographics and comorbidities were comparable between the groups in and outside of IFU. AAA-related and all-cause mortality was similar between these two groups, as was late-onset rupture, need for reintervention, endoleaks, aneurysm sac enlargement, and major operative complications. The sole statistically significant difference in secondary outcomes was increased perioperative blood transfusion in those treated outside the IFU, 13.2% vs 6.2% in those treated within IFU (P = .02); however, this was not associated with decreased access vessel diameter or iliac rupture. When looking at specific criteria, violating the infrarenal aortic neck diameter resulted in increased type I endoleaks (P = .046) and AAA-related mortality (P = .047). Despite most patients being treated outside IFU, there was no difference in outcomes with respect to mortality, rupture, or most major complications. Independently, infrarenal neck diameter was found to be associated with increased AAA-related mortality and type I endoleaks.