Results after elective open repair of pararenal abdominal aortic aneurysms

Abstract

This study presents a retrospective analysis of long-term outcomes and factors influencing early and late results of a 20-year experience with open repair of atherosclerotic pararenal abdominal aortic aneurysms (PAAAs). Records of consecutive patients who underwent open repair of PAAA between 1990 and 2010 at a tertiary referral care center were analyzed for demographics, comorbidities, operative variables, complications, and 30-day mortality. Long-term results were also assessed through a local electronic medical database and direct follow-up. Variables influencing early and late results were evaluated by univariate and multivariate logistic regression analyses, stepwise backward elimination, and Cox proportional hazard regression. The study included 200 patients (94% men; mean age, 69.5years) who were monitored for a mean of 107.3months. The aneurysm was juxtarenal in 78% of patients, suprarenal in 19.5%, and type IV thoracoabdominal in 2.5%. Mortality at 30days was 2.5%. At least one major complication occurred in 51.5%. Postoperative acute renal failure (pARF) occurred in 11% of the patients, 3% had temporary hemodialysis, but only 0.5% required chronic hemodialysis. pARF was significantly related to preoperative renal function (P= .009), visceral ischemia >30minutes (P= .05), and supraceliac or supramesenteric clamp site (P= .005). Respiratory complications (13.8%) were associated with an increasing stage of chronic obstructive pulmonary disease (P= .020), proximal clamp site (P= .047), and intraoperatively infused crystalloids (P= .014). Cardiac complications (12.8%) were related to previous myocardial infarction (P= .031) and proximal clamp site (P= .003). Late deaths were observed in 21.5%. Mean survival was 50months, with Kaplan-Meier survival estimates of 78% at 5years and 60.5% at 10years. Variables influencing long-term survival included age (hazard ratio [HR], 2.67; P= .01), chronic obstructive pulmonary disease stage 2 (HR, 5.14; P= .01) and stage 3 (HR, 4.54; P= .03), postoperative cardiac complication (HR, 3.93; P ≤ .00), previous myocardial infarction (HR, 1.47; P= .02), peripheral artery disease (HR, 1.97; P= .03), and smoking (HR, 1.17; P= .02). Survival and late-onset renal insufficiency were unaffected by preoperative renal function. Late renal failure was observed in 6.2% of the patients but did not predict mortality. Conventional surgical repair of PAAAs can be performed with acceptable short-term and long-term mortality. Although pARF is frequent, chronic hemodialysis at discharge is rare. Cardiac and respiratory complications are also common and associated with worse survival. Our data represent a potentially useful benchmark for complex endovascular repairs of this type of aneurysm.