Multilayer stents affect the final diameter of aortic aneurysms and maintain renal artery patency for a short time in a swine experimental model

Baptista-Strazzi APW was responsible for study conception, data collection, manuscript composition, critical revision, manuscript acceptance, agreement to accountability. Aun R and Wolosker N were responsible for study conception, critical revision, manuscript acceptance, agreement to accountability. Sincos IR was responsible for study conception, data collection, critical revision, manuscript acceptance, agreement to accountability. Tobita AM and Kaufmann O were responsible for data collection, manuscript acceptance, agreement to accountability. Portugal MFC and Paula VP were responsible for manuscript composition, critical revision, manuscript acceptance, agreement to accountability.

Procedure characteristics	Group		p-value
Procedure characteristics	Control (n=5)	Stent (n=6)	p-value
Operation Time (minutes)			0.248^#
Median (Q1; Q3)	195.0 (180.0; 210.0)	180.0 (180.0; 195.0)
Min; Max	180; 220	130; 210
Clamp time (minutes)			0.189^&
Median (SD)	32.2 (11.7)	24.2 (6.9)
Min; Max	18; 50	18; 35
Aneurysmal sac thrombosis			0.061^§
No (n [%])	5 (100.0)	2 (33.3)
Yes (n [%])	0 (0.0)	4 (66.7)
Surgical Complications			0.455^§
No (n (%))	4 (80.0)	6 (100.0)
Yes (n (%))	1 (20.0)	0 (0.0)
Anesthetic Complications			>0.999^§
No (n [%])	4 (80.0)	5 (83.3)
Yes (n [%])	1 (20.0)	1 (16.7)
Post-operatory complications			0.545^§
No ( n [%])	3 (60.0)	5 (83.3)
Yes ( n [%])	2 (40.0)	1 (16.7)
IVUS visualization of aneurysmal sac thrombus			---
No ( n [%])	5 (100)	6 (100)
Patency of renal arteries at re-evaluation procedure			---
Yes ( n [%])	5 (100)	6 (100)

Animal characteristics
Animal study number	Group	Aneurysm Graft	Outcome	Survived until 4-week re-evaluation
Animal 01	control	peritoneum	Ischemia-Reperfusion injury, death before 4 weeks	no
Animal 02	control	peritoneum	Paraplegia followed by euthanasia, death before 4 weeks	no
Animal 03	control	bovine per.	Ischemia-Reperfusion injury, death before 4 weeks	no
Animal 04	Stent	bovine per.	completed study protocol	yes
Animal 05	control	bovine per.	Intestinal occlusion, death before 4 weeks	no
Animal 06	control	bovine per.	completed study protocol	yes
Animal 07	control	bovine per.	completed study protocol	yes
Animal 08	control	bovine per.	completed study protocol	yes
Animal 09	Stent	bovine per.	completed study protocol	yes
Animal 10	Stent	bovine per.	Expansive cervical hematoma, immediate postop. death	no
Animal 11	Stent	bovine per.	Nonresponsive hypotension, immediate postop. death	no
Animal 12	Stent	bovine per.	Paraplegia followed by euthanasia, death before 4 weeks	no
Animal 13	Stent	bovine per.	completed study protocol	yes
Animal 14	control	bovine per.	completed study protocol	yes
Animal 15	Stent	bovine per.	completed study protocol	yes
Animal 16	control	bovine per.	completed study protocol	yes
Animal 17	Stent	bovine per.	completed study protocol	yes
Animal 18	Stent	bovine per.	completed study protocol	yes

Measurements (millimeters)	Control Group		Stent Group
	Aneurysm Construction	Re-evaluation after four weeks	Aneurysm Construction	Re-evaluation after four weeks
	Estimate mean value (95%CI)	Estimate mean value (95%CI)	Estimate mean value (95%CI)	Estimate mean value (95%CI)
Proximal Neck	10.56 (9.25; 11.87)	13.58 (12.27; 14.88)	10.47 (9.27; 11.66)	11.07 (9.87; 12.26)
Aneurysmal sac	17.56 (14.14; 20.98)	19.82 (16.40; 23.24)	17.85 (14.73; 20.97)	12.92 (9.79; 16.04)
Distal Neck	9.62 (8.12; 11.12)	12.86 (11.36; 14.37)	10.20 (8.83; 11.57)	10.72 (9.35; 12.09)

		Re-evaluation Procedure
Animal Characteristics		Aortic Explant			IVUS			Angiogram
Animal study number	Group	Patent Stent	Patent visceral branches	Sac thrombosis	Patent Stent	Patent visceral branches	Sac thrombosis	Patent Stent	Patent visceral branches	Sac thrombosis
Animal 01	control	_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis.	no	_			_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	no^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.
Animal 02	control	_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis.	no	_			_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	no^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.
Animal 03	control	_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis.	no	_			_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	no^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.
Animal 04	stent	yes	yes	yes	yes	yes	not seen	yes	stent	yes
Animal 05	control	_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis.	no	_			_	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	no^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.
Animal 06	control	_	yes	no	_	yes	no	_	yes	no
Animal 07	control	_	yes	no	_	yes	no	_	yes	no
Animal 08	control	_	yes	no	_	yes	no	_	yes	no
Animal 09	stent	yes	yes	yes	yes	yes	not seen	yes	yes	yes
Animal 10	stent	_	_	_	_			yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	no^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.
Animal 11	stent	_	_	_	_			yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	no^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.
Animal 12	stent	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis.	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis.	no				yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	yes^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.	no^* * Re-evaluation hastened by death or complication leading to euthanasia, these were excluded from statistical analysis. ^# # Aortic explant and/or angiograms were also performed in animals with hastened death to exclude occlusions in the aorta, side branches or the device in the stent group.
Animal 13	stent	yes	yes	no	yes	yes	not seen	yes	yes	no
Animal 14	control	_	yes	no	_	yes	no	_	yes	no
Animal 15	stent	yes	yes	yes	yes	yes	yes	yes	yes	yes
Animal 16	control	_	yes	no	_	yes	no	_	yes	no
Animal 17	stent	yes	yes	no	yes	yes	yes	yes	yes	no
Animal 18	stent	yes	yes	yes	yes	yes	yes	yes	yes	yes

Animal characteristics	Group		p-value
Animal characteristics	Control (n=5)	Stent (n=6)	p-value
Age (months)			0.787^#
Median (Q1; Q3)	4 (4; 4)	4 (4; 4)
Min; Max	4; 10	4; 5
Weight (kg)			0.413^&
Median (SD)	53.8 (15.5)	47.5 (8.5)
Min; Max	37; 74	40; 63
Mean Arterial Blood Pressure (mmHg)			0.619^&
Mean (SD)	82.4 (7.1)	86.8 (18.0)
Min; Max	73; 90	64; 113

[1] *Corresponding author. E-mail: mafe.portugal@gmail.com

Brasil

Brasil

Multilayer stents affect the final diameter of aortic aneurysms and maintain renal artery patency for a short time in a swine experimental model

OBJECTIVES:

METHODS:

RESULTS:

CONCLUSION: