Purpose : To present early and midterm results of the periscope endograft (PG) technique to maintain left subclavian artery (LSA) blood flow in thoracic endovascular aortic repairs (TEVAR) involving zone 3. Methods : From April 2010 to January 2013, 14 consecutive high-risk patients (11 men; mean age 70±8 years, range 56-87) underwent TEVAR with the PG technique for 10 thoracic aortic aneurysms (TAA), 2 traumatic aortic ruptures, and 2 aortic dissectionmergently for rupture (3 TAAs and the 2 trauma cases). Two patients had a periscope deployed in an aberrant right subclavian artery. The periscope endografts were sized 1 to 2 mm larger than the branch artery at the intended landing zone. The caudal end was extended distal to the intended distal landing site of the thoracic stent-graft, which was usually deployed after the PG. Both the PG and thoracic stent-grafts were generally molded using the kissing balloon technique. Outcomes analyzed were immediate technical success, perioperative mortality and morbidity, aneurysm diameter change, and periscope endograft patency. Results : Immediate technical success was 100%, with all procedures completed as planned. Perioperatively, one periscope occluded and one of the ruptured TAA patients died. One percutaneous access site hematoma required only conservative management. At a mean follow-up of 26±9 months (range 9-37), there was no additional PG occlusion. The Kaplan-Meier estimate of PG patency was 93% at 2 years. Conclusion : The periscope endograft is a simple technique to maintain perfusion to the LSA in cases where the aortic stent-graft crosses its ostium. The PG technique can be performed transfemorally and even percutaneously, and it can be applied to all supra-aortic branches. Early and midterm results are encouraging, but more experience and long-term results are mandatory before this technique can be widely recommended.