Management and outcomes of symptomatic abdominal aortic aneurysms during the past 20 years.

OBJECTIVE: We compared the management of patients with symptomatic, unruptured abdominal aortic aneurysms (AAAs) treated at a tertiary care center between two decades. This 20-year period encapsulated a shift in surgical approach to aortic aneurysms from primarily open to primarily endovascular, and we sought to determine the effect of this shift in the evaluation, treatment, and clinical outcomes of patients with symptomatic AAA. METHODS: We reviewed 1429 consecutive patients with unruptured AAAs treated at a tertiary care hospital by six staff surgeons between 1995 and 2004 (era 1) and between 2005 and 2014 (era 2). Of those patients, 160 (11%) were symptomatic from their aneurysm and were included in our study. Patient demographics, operative approach, and outcomes were analyzed and compared for each period. RESULTS: Era 1 included 75 patients (71% men; average age, 73.1 ± 10.0 years) treated for symptomatic AAA (91.9% infrarenal, 4.0% juxtarenal, and 4.0% pararenal); of these, 68% were treated with open repair and 32.0% were treated with an endovascular repair. Perioperative mortality during this period was 5.3% (7.8% for the open cohort and 0% for the endovascular cohort). Era 2 included 85 patients (72.9% men; average age 72.0 ± 9.5 years) treated for symptomatic AAA (90.1% infrarenal, 7.5% juxtarenal, and 2.4% pararenal); of these, 29% were treated open and 71% underwent endovascular repair. Perioperative mortality was 5.9% (8.0% for the open cohort and 5.0% for the endovascular cohort). Era 2 had a significantly higher rate of endovascular repair compared with era 1 (71% vs 32%; P < .0001) and a trend toward decreased long-term mortality. The length of stay for era 2 was significantly reduced compared with era 1 (4 days vs 6 days; P = .005). CONCLUSIONS: To our knowledge, this is the largest single-institution cohort of symptomatic AAAs, which comprise 10% to 11% of overall aneurysms. As expected, we found a significant shift over time in the approach to these patients from a primarily open to a primarily endovascular technique. The modern era was also associated with decreased lengths of stay and fewer gastrointestinal and wound complications but no significant differences in overall perioperative mortality.

Use of a proactive duplex ultrasound protocol for hemodialysis access.

OBJECTIVE: Arteriovenous fistula (AVF) creation is the preferred approach for hemodialysis access; however, the maturation of AVFs is known to be poor. We established a proactive early duplex ultrasound (DUS) surveillance protocol for evaluating AVFs before attempted access. This study determined the effect of this protocol related to improving AVF maturation. METHODS: From 2008 to 2013, 153 patients received new upper extremity AVFs and an early DUS surveillance protocol at a single academic institution. The protocol involved an early DUS evaluation before hemodialysis cannulation of the AVF at 4 to 8 weeks after AVF creation. A positive DUS result was identified as a peak systolic velocity of >375 cm/s or a >50% stenosis on gray scale imaging, along with decreased velocity in the outflow vein. Patients with positive DUS findings underwent prophylactic endovascular or open intervention to assist with AVF maturation. Nature of secondary interventions, as well as AVF patency and maturation, were assessed. Overall clinical outcomes and fistula patency were investigated. RESULTS: During the study period, 183 upper extremity AVFs were created in 153 patients, including 82 radiocephalic, 63 brachiocephalic, and 38 brachiobasilic AVFs. A mortality rate of 43% (n = 66) was observed in a median follow-up period of 34.5 months (interquartile range, 19.6-46.9). A total of 164 early DUS were performed at a median of 6 weeks (interquartile range, 3.4-9.6 weeks) after the initial creation. Early DUS showed nine AVFs were occluded and were excluded from further analysis. Hemodynamically significant lesions were found in 62 AVFs (40%); however, only 17 (11%) were associated with an abnormal physical examination. Positive DUS finding prompted a secondary intervention in 81% of the patients. Among those with positive early DUS findings, AVF maturation was 70% in those undergoing a secondary intervention compared with 25% in those not undergoing a prophylactic intervention (P = .011). Primary-assisted patency for AVFs with early positive and negative DUS findings were 83% and 96% at 6 months, 64% and 89% at 1 year, and 52% and 82% at 2 years, respectively (P < .001). CONCLUSIONS: Early DUS surveillance of AVFs before initial access is reasonable to identify problematic AVFs that may not be reliably detected on clinical examination. Although DUS criteria for AVFs have yet to be universally accepted, proactive early postoperative DUS interrogation assists in the early detection of dysfunctional AVFs and improvement of fistula maturation. Despite improved patency in those with positive DUS findings who undergo prophylactic secondary intervention, overall patency remains inferior to those without an abnormality detected on early DUS imaging.