Fenestrated total arch thoracic endovascular aortic repair: coming of age

Total aortic arch replacement is one of the most demanding of cardiovascular surgical procedures despite advances in related surgical technique and anesthesiology. In a recent retrospective study of 3265 patients who underwent open total arch replacement, in-hospital mortality at specialized centers was 10.8%, and permanent neurologic deficit rate was 6.8% [1]. Zone 0 hybrid arch exclusion has similar mortality (10.3% vs. 10.2%) and permanent neurological deficit (8.9% vs. 6.2%) as open total aortic arch replacement [2]. Given this situation, the less invasive alternative of thoracic endovascular aortic repair (TEVAR) seems alluring. But total arch TEVAR faces several challenges, the principal ones being preservation of flow into all the aortic arch branches despite covering their ostia with the arch endograft and avoiding intra-procedural cerebral embolization. Several other problems may be encountered during arch TEVAR, which may be anatomic (tortuous arch, type-3 arch, Gothic arch), hemodynamic (due to the force of left ventricular ejection), device-related (inability to conform to arch anatomy and material fatigue) and access-related (lack of suitable large-bore femoral access, iliac disease and aortic tortuosity) [3]. One or more of these factors may conspire to cause device delivery failure, malposition, malapposition and ultimately treatment failure.
Branched TEVAR, using inner branched devices, is one of two main methods of total arch endovascular repair [4]. The double inner branched arch endograft (Cook Medical, Bloomington, IN, USA) has been the most investigated; early results in 38 patients (technical success 84.2%, 30-day mortality 13.2%, cerebrovascular complications 15.8%) were not optimal [5], but later outcomes with this device have been much better [6]. The technique requires a left carotid to left subclavian bypass to preserve flow into the latter, unless a three-branched version of the endograft is used [7]. There are other limitations: the device has to be custom made, does not appose the aortic wall in the branch-bearing section, has fixed orientation of branches, requires a right carotid or axillary cut-down for delivering the innominate stent, has its proximal sealing zone deep in the ascending aorta (where it may cover ostia of coronary bypass grafts) and the nose cone of the delivery system almost inevitably has to cross the aortic valve [8]. Outcomes obtained with another branched device designed for total arch TEVAR,...


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