Total arch replacement and frozen elephant trunk for aortic dissection in aberrant right subclavian artery

Abstract

Objectives: Aortic dissection (AoD) in the presence of an aberrant right subclavian artery (ARSA) is very rare. Clinical experience is limited, and there is no consensus regarding the optimal management strategy. We seek to evaluate the safety and efficacy of the total arch replacement (TAR) and frozen elephant trunk (FET) technique as an approach to AoD in patients with ARSA by retrospectively analysing our single-centre experience.

Methods: From 2009 to 2017, we performed TAR + FET for 22 patients with ARSA sustaining AoD (13 acute, 59.1%). The mean age was 46.0 years [standard deviation (SD) 8.3], and 19 patients were male (86.4%). ARSA orifice was dilated in 15 (68.2%) patients, and a Kommerall diverticulum was diagnosed in 13 (59.1%) patients with a mean diameter of 21.8 mm (SD 7.7; range 15-40). Surgery was performed via femoral and right/left carotid cannulation under hypothermic circulatory arrest at 25°C. The ARSA was reconstructed using a separate branched graft.

Results: ARSA was closed proximally by ligation in 16 (72.7%) patients, direct suture in 4 (18.2%) patients and both in 2 (9.1%) patients. Operative mortality was 13.6% (3/22). Type Ib endoleak occurred in 1 (4.5%) patient at 8 days. Follow-up was complete in 100% at mean 4.2 years (SD 2.0), during which 3 late deaths and 1 reintervention for type II endoleak occurred. Survival was 81.8% and 76.4% at 3 and 5 years, respectively. Freedom from reoperation was 89.2% up to 8 years. In competing risks analysis, the incidence was 22.1% for death, 10.8% for reoperation and 67.1% for event-free survival at 5 years. The false lumen, ARSA orifice and Kommerall diverticulum were obliterated in 100%. Grafts were patent in 100%. No patients experienced cerebral ischaemia and upper extremity claudication. Hypothermic circulatory arrest time (min) was sole predictor for death and aortic reintervention (hazard ratio 1.168, 95% confidence interval 1.011-1.348; P = 0.034).

Conclusions: The TAR and FET technique is a safe and efficacious approach to AoD in patients with ARSA. Modifications of routine TAR + FET techniques are essential to successful repair, including femoral and right/left carotid artery cannulation, ligation of ARSA on the right side of the trachea and ARSA reconstruction with a separate graft.

Keywords: Aberrant subclavian artery; Aneurysm; Dissection; Frozen elephant trunk; Thoracic aorta; Total arch replacement.