Risk of symptomatic venous thromboembolism after abdominal aortic aneurysm repair in long-term follow-up of 1021 consecutive patients

Objective: Venous thromboembolism (VTE), including deep venous thrombosis and pulmonary embolism (PE), is an infrequent but consequential and potentially preventable complication after major surgical procedures. The aim of the study was to describe the long-term occurrence of symptomatic VTE in patients undergoing abdominal aortic aneurysm (AAA) repair and to ascertain patient-specific risk factors as well as to compare the rate with that of a reference population. Methods: The study included all patients who had undergone endovascular or open AAA repair, both elective and urgent/acute cases, at the Tampere University Hospital (Finland) between February 2001 and December 2016; 59% of patients had undergone endovascular and 41% open repair, and 23% of all cases had required urgent or emergency treatment. Information about later treatment episodes for symptomatic VTE and survival data were obtained from national registries. The reference population was obtained from national registries with a random sample of inhabitants matched for age, sex, and location of residence with a 4:1 ratio and was analyzed similarly. Results: Altogether, 1021 patients and 4065 controls were included (88% male; median age, 74 years in both groups). The high-risk period for VTE lasted for approximately 3 months, and during that time, its occurrence was highest in patients with coronary disease (2.5%), after open repair (2.4%), and in an urgent or emergency setting (2.6%), whereas the rate was low after endovascular aneurysm repair (1.0%). The cumulative incidence of VTE at 3 months, 1 year, 3 years, and 5 years was 1.1%,1.6%, 2.7%, and 4.5% in patients and 0.1%, 0.3%,1.0%, and 1.8% in the reference population, respectively (P < .001 each). Most VTE events were PE in the patient group. The 5-year mortality rates were 37.9% in patients and 23.8% in controls (P < .001). Conclusions: The incidence of symptomatic VTE, particularly PE, after AAA repair is significant, in both short-term and long-term follow-up. Open surgery, acute setting, and concomitant coronary disease appear to increase the risk.