Surgical Outcomes And Postoperative Descending Aorta Morphologic Remodeling After Thoracic Endovascular Aortic Repair For Acute And Chronic Type B Aortic Dissection

Figures & data

Figure 1 Schematic diagram showing the TL, FL and ML area measured directly at the L1, L2 and L3 (dotted lines) levels and the measurements of TI (a/b) and RoC (c/2).

Notes: Level 1: the bronchial bifurcation level; Level 2: the lower edge of the left atrium level; and Level 3: the level of the celiac trunk; a, intra-aorta centerline length between the left subclavian artery and celiac trunk; b, linear distance between the left subclavian artery and celiac trunk; c, distance from the inner wall of the ascending aorta to the inner wall of the descending aorta at the level of the pulmonary artery.
Abbreviations: TL, true lumen; FL, false lumen; ML, maximal lumen; TI, tortuosity index; RoC, radius of curvature.

Figure 2 The definitions and mathematical measurements of the taper ratio (TR), the oversizing ratio (OR) and the mismatch rate (MR) before TEVAR. Pre-TR = 1−(A_DLZ/A_PLZ); Pre-OR = (A_SG/A_DLZ)−1; Pre-MR = D_SG/D_DLZ.

Notes: (A) VR reconstruction images from a patient affected by TBAD. Measurement of the aorta and TL on two planes: DLZ and PLZ. (B) Axial computed tomography scans obtained in the PLZ plane showing the area (A_PLZ) of the TL. (C) Axial computed tomography scans obtained in the DLZ plane showing the area (A_DLZ) and maximal diameter (D_DLZ) of the TL.
Abbreviations: TEVAR, thoracic endovascular aortic repair; DLZ, distal landing zone; PLZ, proximal landing zone; TL, true lumen; A_SG, distal area of the fully expanded stent graft; D_SG, distal diameter of the selected stent graft.

Figure 3 The definitions and mathematical measurements used to calculate the taper ratio (TR), oversizing ratio (OR) and mismatch rate (MR) after TEVAR. Post-TR = 1−(A_DLZ’/A_PLZ’); Post-OR = (A_SG’/A_DLZ)−1; Post-MR = D_SG/D_DLZ’.

Notes: (A) VR reconstruction images from the same patient affected by TBAD. (B) Axial computed tomography scans obtained in the PLZ plane showing the area (A_PLZ’) of the TL. (C) Axial computed tomography scans obtained in the DLZ plane showing the distal TL area (A_DLZ’) and maximal diameter (D_DLZ’) of the TL of the partially expanded stent.
Abbreviations: TEVAR, thoracic endovascular aortic repair; DLZ, distal landing zone; PLZ, Proximal landing zone; TL, true lumen; A_SG’, the distal area of the partially expanded stent graft; D_SG, the distal diameter of the selected stent graft; A _DLZ, is the TL area of the presumed DLZ before TEVAR

Table 1 Baseline Characteristics

Variables	Acute Group No. (%) Or Mean±SD	Chronic Group No. (%) Or Mean±SD	P-value
Age (years)	59.13 ± 9.91	55.92 ± 12.06	0.451
Male	52 (82.5)	18 (78.3)	0.890
Characteristics
Hypertension	58 (92.1)	20 (87.0)	0.762
Smoking	41 (65.1)	16 (69.6)	0.697
Uremia	5 (7.9)	3 (13.0)	0.762
Diabetes	11 (17.5)	4 (17.4)	1
COPD	2 (3.2)	2 (8.7)	0.619
Cardiac disease	5 (7.9)	1 (4.3)	0.920
Carotid disease	2 (3.2)	0	1
Indications for TEVAR
Impending rupture	17 (27.0)	4 (17.4)	0.977
Organ malperfusion	19 (30.2)	2 (8.7)	0.040
Resistant hypertension	15 (23.8)	5 (21.7)	0.841
Refractory pain	24 (38.1)	8 (34.8)	0.778
Aortic growth	4 (6.3)	8 (34.8)	0.003

Abbreviation: TEVAR, thoracic endovascular aortic repair.

Table 2 Procedural Details

Variables	Acute Group No. (%) Or Mean±SD	Chronic Group No. (%) Or Mean±SD	P-value
Stent graft type			0.23
Captivia	43 (68.3)	12 (52.2)
Zenith	7 (11.1)	2 (8.7)
Ankura	12 (19.0)	7 (30.4)
Grink	1 (1.6)	2 (8.7)
Tapered SG	15 (23.8)	11(47.8)	0.03
Median length, mm	182.96±22.32	193.35±13.60	0.02
Coverage LSA (n, %)			0.44
Total coverage	26 (41.3)	13 (56.5)
Partial coverage	20 (31.7)	5 (21.7)
Adjunctive procedures
Subclavian chimney	3 (4.8)	0	0.29
Restrictive bare stent	8 (12.7)	10 (43.5)	0.002
Distal stent graft extensions			0.91
Renal artery bare stent	2 (3.2)	2 (8.7)
Mesenteric artery bare stent	3 (4.8)	0
Ilio-femoral artery bare stent	1 (1.6)	0

Abbreviation: LSA, left subclavian artery.

Table 3 Complications And Results

Variables	Acute Group No. (%) Or Median	Chronic Group No. (%) Or Median	P-value
Technical success	63 (100)	23 (100)
Follow-up, months	34(26)	36(30)
30-day mortality	0	1 (4.3)	0.267
30-day aortic-related mortality	0	1 (4.3)	0.267
>30-day mortality	2 (3.2)	2 (9.1)	0.587
>30-day aortic-related mortality	1 (1.6)	1 (4.5)	0.453
Aortic rupture	0	2 (8.7)	0.069
Endoleak	4 (6.3)	2 (8.7)	0.576
Distal SINE	2 (3.2)	1 (4.3)	1
RTAD	1 (1.6)	0	1
Distal stent collapse	0	3 (13.04)	0.017
Stroke	3 (4.8)	1 (4.3)	1
Spinal ischemia or paraplegia	2 (3.2)	1 (4.3)	1
Renal failure	4 (6.3)	3 (13.0)	0.576
Secondary intervention	2 (3.2)	1 (4.3)	1

Abbreviations: SINE, stent graft-induced new entry; RTAD, retrograde type A dissection.

Table 4 Preoperative Descending Aorta Morphology Between The Acute And Chronic Groups

Variables	Acute Group Mean±SD Or Median	Chronic Group Mean±SD Or Median	P-value
True lumen area, mm^2
L1	342.3 ± 107.1	421.5 ± 121.7	0.004
L2	314.4 ± 97.3	250.1 ± 84.2	0.006
L3	263.4 ± 95.3	268.2 ± 78.1	0.829
False lumen area, mm^2
L1	485.4 ± 292.6	1445.0 ± 643.3	0.000
L2	498.5 ± 199.4	1375.2 ± 581.5	0.000
L3	356.9 ± 114.6	619.5 ± 273.6	0.000
Maximal lumen area, mm^2
L1	827.7 ± 384.4	1866.5 ± 712.4	0.000
L2	812.9 ± 516.9	1625.3 ± 535.7	0.000
L3	620.3 ± 324.4	887.7 ± 422.6	0.003
TR	0.57 (0.49)	0.74 (0.60)	0.000
OR	2.75 ± 1.89	3.96 ± 2.27	0.022
MR	1.23 ± 0.15	1.20 ± 0.19	0.467
TI	1.22 (1.19)	1.41 ± 0.17	0.000
RoC, mm	26.05 ± 4.64	28.26 ± 4.56	0.052

Abbreviations: TEVAR, thoracic endovascular aortic repair; TR, taper ratio; OR, oversizing ratio; MR, mismatch ratio; TI, tortuosity index; RoC, radius of curvature.

Figure 4 Area of the TL, FL and ML regression trends at different measured levels, along with the time before and after thoracic endovascular aortic repair (TEVAR).

Notes: Level 1: the bronchial bifurcation level; Level 2: the lower edge of the left atrium level; and Level 3: the level of the celiac trunk.
Abbreviations: TL, true lumen; FL, false lumen; ML, maximal lumen; Pre, pre-TEVAR; Post, Post-TEVAR; mo, months.

Table 5 Changes In Preoperative To Postoperative Descending Aorta Morphology Between The Acute And Chronic Groups

Variables	Acute Group Mean±SD	Chronic Group Mean±SD	P-value
Change in TR	0.29 ± 0.17	0.28 ± 0.16	0.685
Change in OR	1.80 ± 0.86	2.98 ± 1.85	0.028
Change in MR	0.11 ± 0.22	0.03 ± 0.21	0.323
Change in TI	0.00 ± 0.09	0.09 ± 0.10	0.000
Change in RoC, mm	1.53 ± 2.65	−0.030 ± 2.63	0.116

Abbreviations: TR, taper ratio; OR, oversizing ratio; MR, mismatch ratio; TI, tortuosity index; RoC, radius of curvature.