Dialysis-associated muscle cramps related to high-flow arteriovenous fistula and high cardiac output failure reversed with fistula ligation.

Muscle cramps are common in patients undergoing haemodialysis, but their pathophysiology is not well understood. The effect of regional blood flow reduction on the neuromuscular compartment as a result of a high-flow arteriovenous fistula (HFAVF) was not previously implicated in dialysis-associated muscle cramps. We report a patient with HFAVF (blood flow rate 2450 ml/min) causing high cardiac output failure who developed severe muscle cramps during dialysis, significantly limiting ultrafiltration and causing fluid overload. Ligation of the fistula resulted in complete reversal of muscle cramps, allowing for adequate ultrafiltration. This case highlights the need for clinical vigilance and potential screening for HFAVF in dialysis patients presenting with persistent muscle cramps.