Flow-limiting lesions or embolic phenomena can produce vertebrobasilar ischemia. This study aims to differentiate the pathophysiology of vertebral ischemia and examine contemporary outcomes after distal vertebral reconstruction.Methods
Between February 2005 and November 2011, 41 consecutive distal vertebral artery (VA) reconstructions were performed in 34 patients, including bypass to the third portion of the VA (V3) at the C1–2 level (n = 24) or the C0–1 level (n = 7); transposition of the external carotid artery or its occipital branch onto V3 (n = 6); transposition of V3 onto the internal carotid artery (n = 3); and bypass from the ipsilateral subclavian artery to V3 (n = 1). Six patients required a concomitant carotid intervention, and nine patients required a partial resection of the C1 transverse process. Symptoms, present in 91% of patients, were attributed to a flow-limiting lesion in 16 (52%), to embolization in nine (29%), and to a mixed etiology in six (19%).Results
Intraoperatively, five patients required graft revision or conversion of a transposition to a bypass, and two patients required vertebral ligation. Median blood loss was 260 mL. Median hospital length of stay was 1 day. Postoperatively, one patient (2%) required re-exploration for bleeding, a stroke occurred in one patient (2%), and cranial nerve injury occurred in three patients (7%). There were no perioperative deaths. Survival analysis showed that primary patency at 1, 2, and 5 years, respectively, was 74%, 74%, and 54%. Secondary patency was 80% at 1 year and remained so through the end of follow-up at 80 months. A statistically significant difference in patency was noted favoring arterial transposition over vertebral bypass of 100%, 100%, and 83% at 1, 2, and 5 years, respectively, vs 65%, 65%, and 39% (P = .018). Considering successful redo bypass grafting for late failure, 97% of patients demonstrated preserved patency at their last follow-up. There were two late deaths of unknown etiology and no late strokes.Conclusions
Distal VA reconstruction for flow-limiting or embolic lesions provides excellent stroke protection and symptomatic relief with acceptable perioperative risk in selected patients.