Cardiac Complications following Creation of Arteriovenous Access in Medicare Beneficiaries with ESKD

Background: Arteriovenous fistulas (AVFs) and grafts (AVGs) are the preferred long-term hemodialysis access for the majority of patients, but produce hemodynamic changes that contribute to cardiac complications including heart failure, pulmonary hypertension, and atrial arrhythmia. This cohort study leverages nationwide claims data to examine adverse cardiac events associated with AVGs and AVFs among patients with ESKD. Methods: We performed a retrospective cohort study using 100% Medicare fee-for-service claims to identify adults with ESKD undergoing AVF or AVG creation from 2017−2024. The primary outcome was hospitalization for a composite adverse cardiac event (heart failure, pulmonary hypertension, or atrial fibrillation or flutter) within 1 year. Secondary outcomes included the composite outcome through 5 years, its individual components, all-cause hospitalization, and flow-reduction procedures. Cumulative incidence functions were estimated using Fine-Gray subdistribution hazard models. Independent variable analyses were conducted for the primary outcome. Results: We identified 210,002 accesses (mean age 66.3 years; 43% female) including 147,709 (70%) AVFs and 62,293 (30%) AVGs. AVG recipients had a greater burden of baseline comorbidity and cardiovascular disease. Through 1 year, the cumulative incidence of hospitalization for an adverse cardiac event was 40% (AVF 39%, AVG 44%, P < .001), constituting 61% of all-cause hospitalizations. Heart failure predominated (AVF 33%, AVG 37%, P < .001), followed by atrial fibrillation or flutter (AVF 19%, AVG 21%, P < .001), and pulmonary hypertension (AVF 8%, AVG 9%, P < .001). Older age (≥ 50 years), AVG creation, pre-existing pulmonary hypertension, and atrial arrhythmia were independently associated with a higher hazard of the primary outcome (P < .05). Conclusions: The high rate of hospitalization for adverse cardiac events in the first year after arteriovenous access creation supports consideration of strategies (e.g., lower-flow forearm access, flow-volume surveillance) to mitigate the hemodynamic consequences of long-term arteriovenous access.