A modified frozen elephant trunk technique for acute Stanford type A aortic dissection

Abstract

Background: Acute Stanford type A aortic dissection is often fatal, with a high mortality rate and requiring emergency intervention. Salvage surgery aims to keep the patient alive by addressing severe aortic regurgitation, tamponade, primary tear, and organ malperfusion and, if possible, prevent the late dissection-related complications in the proximal and downstream aorta. Unfortunately, no optimal standard treatment or technique to treat this disease exists. Total arch replacement with frozen elephant trunk technique plays an important role in treating acute type A aortic dissection. We aim to describe a modified elephant trunk technique and report its short-term outcomes.

Methods: From February 2018 to August 2019, 16 patients diagnosed with acute Stanford type A aortic dissection underwent surgery with the modified frozen elephant trunk technique at Xiamen Heart Center (male/female: 9/7; average age: 56.1 ± 7.6 years). All perioperative variables were recorded and analyzed. We measured the diameters of the ascending aorta, aortic arch, and descending aorta on the bifurcation of the pulmonary and abdominal aortas and compared the diameters at admission, before discharge, and 3 months after discharge.

Results: Fifteen patients (93.8%) had hypertension. The primary tears were located in the lesser curvature of the aortic arch and ascending aorta in 5 (31.3%) and 9 patients (56.3%), respectively, and no entry was found in 2 patients (12.5%). The dissection extended to the iliac artery and distal descending aorta in 14 (87.6%) and 2 patients (12.5%), respectively. The duration of cardiopulmonary bypass (CPB), cross-clamping, and antegrade cerebral perfusion were 215.8 ± 40.5, 140.8 ± 32.3, and 55.1 ± 15.2 min, respectively. Aortic valve repair was performed in 15 patients (93.8%). Bentall procedure was performed in one patient (6.3%). Another patient received coronary artery repair (6.3%). The diameters at all levels were greater on discharge than those on admission, except the aortic arch. After 3 months, the true lumen diameter distal to the frozen elephant trunk increased, indicating false lumen thrombosis and/or aortic remodeling.

Conclusions: The modified frozen elephant trunk technique for acute Stanford type A aortic dissection is safe and feasible and could be used for organ malperfusion. Short-term outcomes are encouraging, but long-term outcomes require further investigation.

Keywords: Acute Stanford type a aortic dissection; Fenestration; Frozen elephant trunk.

Fig. 1

a: The illustration of a “fenestrated” frozen elephant trunk for Stanford A dissection; b: The red arrow and the black arrow indicate continuous suture and circumferential suture to prevent endoleak; the blue arrow indicates continuous mattress suture. c: The illustration of the “fenestration”

Fig. 2

CTA about the aorta at different levels at admission,before discharge, and 3 months after discharge. The upper four pictures stands for the aorta at the bifurcation of the pulmonary artery, aortic arch, and diaphragm and at the bifurcation of the common iliac artery when admitted in hospital (a-d). The middle and final four pictures stands for the aorta at the bifurcation of the pulmonary artery, aortic arch,and diaphragm and at the bifurcation of the common iliac artery when before discharge(e-h) and 3 months after discharge(i-l)

Fig. 3

Three-dimensional reconstruction of the aorta at admission, before discharge,and 3 months after discharge(a-c)

Fig. 4

a: Changes of true lumen of descending aorta at diaphragm muscle site. b: Changes of true lumen of descending aorta at distal stent site. c: Changes of true lumen of descending aorta at celiac axis site