Preoperative mapping venography in patients who require hemodialysis access: imaging findings and contribution to management.

PURPOSE: To analyze the use of preoperative venographic mapping in patients who require permanent hemodialysis access.

MATERIALS AND

METHODS

Ninety-one patients underwent 108 preoperative studies. Sixty-eight (75%) were documented to have ongoing or previous hemodialysis at the time of the study. A total of 154 arms were assessed with venograms (75 right, 79 left); 74 of the patients (81%) had previous access. Venographic mapping was not performed in patients with clearly usable veins as determined by the referring surgeon.

RESULTS

A total of 170 veins were suitable for access creation (ie, continuous vein of suitable caliber). Of these, 78 were used (40 fistulas [51%] and 38 grafts [49%]), and 87% of accesses were successfully used for dialysis (73% primarily, 14% after additional intervention). Anatomic variants included early brachial-basilic confluence (44%), double terminal cephalic arch (4%), and brachial-basilic "ladders" (7%). Significant central venous stenosis was found in 10% of studies, limiting the ability to use the affected side for access. There were significant associations between (i) the number of previous accesses and access type created (P = .002, Fisher exact test) and (ii) the number of veins visualized and access type created (P < .001, Fisher exact test). A greater number of previous access attempts correlated with graft rather than fistula placement for permanent access, and increased numbers of veins seen on venography correlated with an increased chance of permanent access placement.

CONCLUSIONS

Venography may identify clinically occult veins usable for hemodialysis access. Anatomic variants are common and may affect choice of access site.