Effect of hemodialysis access blood flow on cardiac events after coronary artery bypass grafting using an internal thoracic artery.

Background: The possibility of coronary steal through an arteriovenous fistula (AVF) in hemodialysis (HD) patients with coronary artery bypass grafts (CABGs) using an ipsilateral internal thoracic artery (ITA) has been suggested. In order to define the significance of such a possibility, we analyzed cardiac events and mortality risk in patients in relation to AVF flow. Methods: A retrospective cohort study was performed on prevalent HD patients from a single center. The outcomes included a first cardiac event, cardiac death and death from any cause. Results: The group consisted of 23 chronic HD patients having ITA CABG and upper extremity AV access, 12 patients had an ipsilateral and 11 patients had a contralateral location of ITA CABG and an upper extremity AV access. The mean follow-up period was for 37.0 months. Multivariable Cox proportional-hazards regression analysis of risk of death from any cause in relation to AV access flow showed no increased risk, neither in the group with ipsilateral location of ITA grafts and dialysis accesses (adjusted HR, 3.047 [95% CI, 0.996 to 1.000], p = 0.081), nor in the group with contralateral location of both shunts (adjusted HR, 0.173 [95% CI, 0.997 to 1.002], p = 0.678). There was no significant correlation between AV access blood flow and the risk of first cardiac event as well as cardiac death in either study group. Conclusions: In this study on HD patients having ipsilateral ITA CABG and AVF, fistula flow rate was not found to be associated with mortality or cardiac risk.