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Extra-Intracranial Standard Bypass in the Elderly: Perioperative Risk, Bypass Patency and Outcome

Background: Patients with chronic atherosclerotic vessel occlusion and cerebrovascular hemodynamic insufficiency may benefit from extra-intracranial (EC-IC) bypass surgery. Due to demographic changes, an increasing number of elderly patients presents with cerebrovascular hemodynamic insufficiency. So far, little data for EC-IC bypass surgery in elderly patients suffering occlusive cerebrovascular disease are available. We therefore designed a retrospective study to address the question whether EC-IC bypass is a safe and efficient treatment in a patient cohort ≥70 years. Methods: 50 patients underwent EC-IC standard bypass surgery with translocation of the superficial temporal artery to an M2 segment of the medial cerebral artery. Criteria for bypass surgery were presence of symptomatic occlusive cerebrovascular disease of the anterior circulation and proof of a severely restricted or abrogated reserve capacity (detected by H2O-photon emission tomography or single photon emission computer tomography - before and after forced vessel dilatation by diamox). The incidence of perioperative neurological and surgical complications, bypass patency, bypass function and short-term outcome were retrospectively analyzed. Results: The study cohort consisted of 16 patients ≥70 years (mean = 74.3 years, SE 1.3). It was compared to a cohort of 34 patients <70 years (mean = 61.2 years, SE 1.0). Both groups underwent EC-IC bypass surgery after careful preoperative work-up. Both patient groups did not differ significantly in gender, vascular pathology, previous history of diseases/comorbidity or clinical symptoms. The number of patients which underwent stenting or other endovascular treatments of the internal or common carotid artery prior to EC-IC bypass surgery was significantly higher in the group of patients ≥70 years (37.5 vs. 0%, p < 0.001). Perioperative stroke rate was 0% in both groups and mild morbidity occurred in 18.8 and 14.7%, respectively (p = 0.699). One 84-year-old female patient died due to perioperative endocarditis. Initial bypass patency was 93.8% in patients above the age of 70 years and 97.1% in the younger group (p = 0.542). Secondary occlusion rate was low in both groups (≥70 years: 0% vs. <70 years 3.7%). No new neurologic deficit occurred in patients with a patent bypass during the follow-up period (median 18 ± 13.1 months). Two patients with an initially occluded bypass and one with a secondary bypass occlusion suffered from new neurological symptoms. Conclusions: Our data show comparable safety and efficiency of EC-IC bypass surgery in patients under and above the age of 70 years due to a careful preoperative work-up and a strict indication for bypass surgery.