Arteriovenous Fistula-Associated Ascites

Introduction: Dialysis-associated ascites (DAA) is a diagnosis of exclusion in End-Stage Kidney Disease (ESKD). The prognosis is grim and typically obviates kidney transplantation. We present a case of refractory ascites in a hemodialysis (HD) patient initially diagnosed as DAA, later determined to be cardiac ascites from arteriovenous fistula (AVF) related high-output heart failure (HOHF). The ascites resolved and the HOHF improved with AVF ligation and the patient was subsequently able to receive a kidney transplant. Case Description: A 43 year-old woman with ESKD on HD via a mildly aneurysmal AVF developed ascites with a serum albumin ascitic gradient (SAAG) < 1.1 g/dL. After comprehensive workup for ascites, she was diagnosed with DAA. Later she was found to have an ejection fraction (EF) of 25% and due to this plus her ascites, she was deemed to not be a kidney transplant candidate. Doppler studies of the AVF showed elevated peak systolic velocities and subsequent right heart catheterization (RHC) revealed a high cardiac index (CI) that normalized upon AVF occlusion (see Table). After AVF ligation and tunneled dialysis catheter placement for HD, her EF improved to 45% and ascites resolved in 3 months. She became eligible for and received a kidney transplant 9 months later. Discussion: DAA is a diagnosis of exclusion and has a mortality rate of 45% within 15 months of diagnosis. While a kidney transplant is the definitive treatment, our patient was unsuitable due to her reduced EF and ascites. Flow studies of her AVF were elevated and subsequent RHC revealed an abnormally high CI that normalized with AVF occlusion. An AVF alters peripheral circulation hemodynamics, reducing resistance and increasing cardiac output. Excessive blood influx can raise central venous pressure and left ventricular end-diastolic pressure, resulting in HOHF and cardiogenic ascites. With AVF ligation, her EF improved to 45%, ascites resolved, and she recieved a kidney transplant. This case emphasizes the need to consider AVF related HOHF as a reversible cause of ascites in the patient with ESKD, especially if the AVF is aneurysmal. Cardiac output (CO) and Index (CI) before and after AVF occlusion with a BP cuff - Condition CO CI (nl 2.6-4.2) Baseline 6.7L/min 4.5L/min Cuff Inflated 4.1L/min 2.7L/min Cuff Deflated 6.7L/min 4.4L/min