Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. 2014, 158(4):562-568 | DOI: 10.5507/bp.2013.021

Evaluation of a novel vascular graft with a distal bifurcation designed to reduce the development of intimal hyperplasia. Experimental study in a porcine aorta model

Robert Vlachovsky^a, Robert Staffa^a, Martin Dvorak^a, Michal Vlasin^b, Marketa Hermanova^c, Thomas O'Brien^d, Timothy McGloughlin^d

^a Second Department of Surgery, St. Anne's University Hospital in Brno and Faculty of Medicine, Masaryk University, Brno, Czech Republic

^b Dogs & Cats Clinic, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences Brno

^c First Department of Pathological Anatomy, St. Anne´s University Hospital in Brno and Faculty of Medicine, Masaryk University, Brno

^d Centre for Applied Biomedical Engineering Research, Department of Mechanical and Aeronautical Engineering and Materials and Surface Science Institute, University of Limerick, Limerick, Ireland

Objective: Abnormal haemodynamics is commonly agreed to be a major contributor to the development of distal anastomotic intimal hyperplasia. A new vascular graft design proposed by computational studies was used to demonstrate its surgical feasibility and to compare it with the conventional graft in a porcine model.

Method: The device was used in 12 eight-month-old pigs, six received the new graft and six had a conventional graft. The proximal graft end was implanted into the aorta, the distal graft end was implanted into the iliac artery. The host artery was ligated in order to simulate occlusion. At 20 weeks after surgery the pigs were killed and the device was excised for histological and morphometric analysis.

Results: In five experimental grafts the reconstruction was occluded due to thrombosis; only one prosthesis was patent showing a minimum of neointimal hyperplasia. In the control group too only three of the six grafts were patent. A histological analysis revealed, as the cause of occlusion, fibrous tissue overgrowth corresponding in structure to neointimal hyperplasia. Differences in the number of obliterations and in occlusion rates between the profiles of the two groups were evaluated using the median test (P<0.05). The results were not statistically significant.

Conclusion: Although mathematical modelling had shown significant haemodynamic benefits of a naturally bifurcated graft, our study did not confirm its superiority over conventionally used prostheses.

Keywords: animal model, anastomosis, graft design, distal bifurcation, intimal hyperplasia, experimental study, pig

Received: August 25, 2012; Accepted: March 12, 2013; Prepublished online: April 10, 2013; Published: December 9, 2014  Show citation