Thorac cardiovasc Surg
DOI: 10.1055/s-0039-1687887
Original Basic Science
Georg Thieme Verlag KG Stuttgart · New York

Experimental Studies for Small Diameter Grafts in an In Vivo Sheep Model—Techniques and Pitfalls

1  Department of Cardiothoracic Surgery, Uniklinik Köln, Köln, Germany
,
Maria Guschlbauer
2  Dezentrales Tierhaltungsnetzwerk, Universitätsklinikum Köln, Cologne, Germany
,
1  Department of Cardiothoracic Surgery, Uniklinik Köln, Köln, Germany
,
Max Theodor Wacker
3  Department of Cardiac Surgery, Universitatsklinikum Magdeburg, Magdeburg, Germany
,
Stefanie Reinhardt
1  Department of Cardiothoracic Surgery, Uniklinik Köln, Köln, Germany
,
1  Department of Cardiothoracic Surgery, Uniklinik Köln, Köln, Germany
,
Anton Sabashnikov
1  Department of Cardiothoracic Surgery, Uniklinik Köln, Köln, Germany
,
Alexandra Maul
4  Department of Experimentelle Medizin, Universitätsklinikum Köln, Cologne, Germany
,
Anja Sterner-Kock
4  Department of Experimentelle Medizin, Universitätsklinikum Köln, Cologne, Germany
,
Thorsten C.W. Wahlers
1  Department of Cardiothoracic Surgery, Uniklinik Köln, Köln, Germany
,
Maximilian Scherner
3  Department of Cardiac Surgery, Universitatsklinikum Magdeburg, Magdeburg, Germany
,
Jens Wippermann
3  Department of Cardiac Surgery, Universitatsklinikum Magdeburg, Magdeburg, Germany
› Author Affiliations
Further Information

Publication History

25 December 2018

05 March 2019

Publication Date:
28 April 2019 (online)

Abstract

Background Scientific attempts to create the “ideal” small diameter vascular graft have been compared with the “search of the holy grail.” Prosthetic material as expanded polytetrafluoroethylene or Dacron shows acceptable patency rates to large caliber vessels, while small diameter (< 6 mm) prosthetic conduits present unacceptably poor patency rates. Vascular tissue engineering represents a promising option to address this problem.

Material and Methods Thirty-two female Texel-sheep aged 6 months to 2 years underwent surgical common carotid artery (CCA) interposition using different tissue-engineered vascular substitutes. Explantation of the grafts was performed 12 (n = 12) and 36 (n = 20) weeks after surgery. Ultrasound was performed on postoperative day 1 and thereafter every 4 weeks to evaluate the graft patency.

Results The average length of implanted substitutes was 10.3 ± 2.2 cm. Anesthesia and surgical procedure could be performed without major surgical complications in all cases.

The grafts showed a systolic blood flow velocity (BFV) of 28.24 ± 13.5 cm/s, a diastolic BFV of 9.25 ± 4.53 cm/s, and a mean BFV of 17.85 ± 9.25 cm/s. Native vessels did not differ relevantly in hemodynamic measurements (systolic: 29.77 cm/s; diastolic: 7.99 cm/s ±  5.35; mean 15.87 ± 10.75). There was no incidence of neurologic complications or subsequent postoperative occlusion. Perioperative morbidity was low and implantation of conduits was generally well tolerated.

Conclusion This article aims to give a precise overview of in vivo experiments in sheep for the evaluation of small diameter vascular grafts performing CCA interposition, especially with regard to pitfalls and possible perioperative complications and to discuss advantages and disadvantages of this approach.

Author contributions

Conception and design: KE, MG, TCWW, SM, JW.


Analysis and data interpretation: KE, MG, WB, MTW, SR, ID, AS, AM, ASK, TCWW, SM, JW.


Data collection: KE, MG, WB, MTW, SR, ID, AS, AM, ASK, TCWW, SM, JW.


Writing the article: KE, MG.


Critical revision of the article: KE, MG, WB, MTW, SR, ID, AS, AM, ASK, TCWW, SM, JW.


Final approval of the article: KE, MG, WB, MTW, SR, ID, AS, AM, ASK, TCWW, SM, JW.


SM and JW share the senior authorship.


Both authors contributed equally to this manuscript.