Aims: Biomechanical evaluation of small blood vessels and vascular grafts is an important task. In this work a method is presented for testing mechanical behaviour of very small tubular structures with less than 1mm diameter.

Methods: For the tensile measurements a BOSE ElectroForce system (Bose Corp. MN, USA) with a controllable linear motor for static and dynamic measurements was used. To measure very small ring-shaped specimens the system was modified with a cantilever and a special designed probe fixation.

Firstly, tensile behaviour on thoracic mice aortae after 19 weeks high-fat-diet (group 1) and a control group (group 2) were analyzed. Secondly, on electrospun vascular grafts repeated loading-unloading measurements were performed to obtain the dynamic behaviour in the physiological range.

Results: The modified system allowed measurements on very small specimen (0.7mm inner diameter in case of the mice aortae) and the use of very sensitive load cells of 10N and up to 0.5N.

For the mice aortae significant higher maximum tear forces in group 1 with 0.41 +/− 0.12N, than in group 2 with 0.34 +/− 0.10N were measured. Diverse tear forces and braking strains at different zones of the aorta could be observed. For the vascular grafts hysteresis curves could be recorded with peak-to-valley forces of 0.03 to 0.08N, corresponding to 80 and 120mmHg.

Conclusion: The established method enables a reproducible and sensible measurement of static and dynamic mechanical properties in small ring-shaped specimen of arteries and vascular prostheses.