Non-Invasively Assessed Haemodynamics in Patients with High Flow Arteriovenous Fistula and High Output Cardiac Failure

We have read with interest the recent paper in this journal by Lee et al.1 The authors examined 109 haemodialysis patients by detailed echocardiography and measured haemodialysis arteriovenous fistula (AVF) flow in a retrospective study. Then they followed them for a mean of 25 months, and during this time, 19 (17.4%) patients were hospitalized for high-output cardiac failure (HOCF). Lower estimated systemic vascular resistance (eSVR) was the best predictor of the hospitalization. Systemic vascular resistance (SVR) was estimated by the ratio of systemic blood pressure and velocity time integral of the left ventricular outflow tract. HOCF (or sometimes HOHF) is a relatively rare HF phenotype characterized by the combination of HF signs and symptoms together with cardiac index (CI) above 3.9 L/min/m2.2 High AVF flow represents one of the common aetiologies and is thus more frequent in patients on chronic haemodialysis where AVF is used as the vascular access,3, 4 and the study by Lee et al. was unique by the hospitalization records. The authors are supported by the Ministry of Health, Czech Republic-DRO (General University Hospital in Prague-VFN), 00064165.