Noninvasive assessment of arteriovenous fistula.

Noninvasive diagnostic techniques permit objective assessment of the presence, location, and hemodynamic alterations associated with congenital or acquired arteriovenous fistulas. Doppler ultrasound may be used to assess abnormal velocity signals and directional blood flow in afferent and efferent limbs of the fistula, as well as abnormal pressure gradients in the involved extremity. Plethysmography permits graphic qualitative assessment of pulse wave form alterations before and after compression of the fistula. In addition, venous occlusion plethysmography permits quantitation of limb or digit blood flow before and after fistula. In addition, venous occlusion plethysmography permits quantitation of limb or digit blood flow before and after fistula compression. Illustrative cases of congenital and acquired arteriovenous fistulas demonstrate the utility of these noninvasive techniques in the objective assessment of patients.