Arteriovenous graft patency outcomes and prognostic factors

Abstract

Objectives: Arteriovenous graft for hemodialysis shows poorer outcomes than arteriovenous fistula, due to frequent stenosis and thrombosis. We investigated arteriovenous graft patency outcomes and prognostic factors for these outcomes.

Methods: We included a single-center cohort of patients receiving arteriovenous graft for hemodialysis access from 2010 to 2014. Demographics, laboratory data, comorbidities, and medications were collected from medical records. Surgical factors related to graft operation including the type and diameter of connected vessels, graft location, and type of operation (elective or emergency) were also recorded. Outcomes included primary and secondary patency. Survival analysis was conducted using the Kaplan-Meier method; univariate and multivariate analyses were used to evaluate the prognostic factors.

Results: Data from 225 grafts were analyzed. During the follow-up period (mean: 583 days, range: 1-1717 days), 138 (61%) grafts required intervention and 46 (20%) permanently failed. Primary patency at one, two, and three years was 42%, 20%, and 16%, respectively. Secondary patency at one, two, and three years was 85%, 72%, and 64%, respectively. Multivariate analysis showed that primary patency was negatively associated with increasing age and location of vessel anastomosis (reference-brachiobrachial anastomosis; brachiobasilic - HR, 0.569; 95% CI, 0.376-0.860; p = 0.007; brachioaxillary anastomosis - HR 0.407; 95% CI, 0.263-0.631; p < 0.0001); secondary patency was positively associated with diastolic blood pressure, serum albumin level, and hemoglobin over 10 g/dL. Adverse events other than stenosis or thrombosis, such as infection/inflammation or pseudoaneurysm were observed in approximately 20% of grafts.

Conclusions: Factors associated with diminished primary arteriovenous graft patency included increased patient age and location of vessel anastomosis (brachiobrachial type compared to brachiobasilic or brachioaxillary type); diminished secondary patency was associated with low diastolic blood pressure, low serum albumin, and hemoglobin level under 10 g/dL. Among these factors, diastolic blood pressure, serum albumin, and hemoglobin level may be modifiable and could improve arteriovenous graft patency outcomes.

Keywords: Arteriovenous graft; hemodialysis access; patency outcome; primary patency; secondary patency.