Anatomic severity grading score predicts technical difficulty, early outcomes, and hospital resource utilization of endovascular aortic aneurysm repair

Abstract

In 2002, a system for the grading of abdominal aortic aneurysms (AAAs) was developed by the Society for Vascular Surgery (SVS). Because the correlation of the anatomic severity grading (ASG) score to patient outcomes has yet to be validated, we provide our experience with calculating the ASG score using three-dimensional (3-D) image-rendering software and provide the practical translation of this score into early outcomes and hospital charges. All patients who underwent an endovascular aneurysm repair (EVAR) for infrarenal AAAs between 2009 and 2010 were retrospectively reviewed for demographics, intraoperative data, and 30-day outcomes. ASG scores were calculated from morphologic measurements, and two independent patient groups were created: those with a low ASG score (score <14) and a high ASG score (score ≥14). We identified 108 patients (mean age, 75 years), of whom 56 were in the low-score ASG group and 52 were in the high-score ASG group. Operative outcomes significantly different in the low-score group vs high-score group were number of endograft implants (three vs four, P = .001), operative time (113 vs 210 minutes, P < .0001), blood loss (227 vs 866 mL, P = .0002), and contrast volume (100 vs 131 mL, P = .032). In the low-score group compared with the high-score group, access site adjuncts were 14% vs 50% (P < .0001), and intraoperative adjuncts were 54% vs 80% (P = .004). Most adjuncts (75%) were endovascular. No EVARs were converted to open. Mean hospital stay was 2 days for the low-score group and 5 days for the high-score group (P = .012). The 30-day operative mortality was zero. No aneurysm-related deaths occurred during follow-up. In the low-score vs high-score groups, mean operating room supply charge was $16,646 vs $25,765 (P = .006), and the mean total hospital charge was $70,956 vs $105,153 (P = .016). The anatomic severity grading score can be easily and rapidly calculated from computed tomography images with the aid of 3-D image-rendering software. The anatomic severity grading score correlates with the technical difficulty of EVAR and the extent of hospital resource utilization.