The hemodynamics of steal syndrome and its treatment.

A 61-year-old man developed steal syndrome after creation of a transposed basilic vein arteriovenous fistula (AVF) resulting in rest pain and ischemic ulcers in the fingertips. Our initial surgically created stenosis reduced the diameter by 32% and the area by 56%, and increased the radial artery pressure from 52 to 78 mmHg, with relief of symptoms. Within 3 weeks his symptoms reappeared. Repeat measurements did not explain his return of symptoms. A second area of stenosis was created in the AVF, with a diameter reduction of 75%, and an area reduction of 94%. His symptoms resolved, and his ulcers healed. The hemodynamics of the AVF and the steal syndrome were evaluated by duplex imaging and Doppler pressure assessment. A greater stenosis increased the radial artery pressure from 78 to 140 mmHg while maintaining flow through the AVF. Rather than increasing the degree of stenosis at the first site, we created a second area of stenosis. Hemodynamically, this would be additive to the first without the risk of creating a high-grade stenosis that could thrombose the AVF. Increasing the resistance in the AVF will decrease flow in the AVF and, ultimately, increase flow to the hand.