Development of a demonstration model of a rotational atherectomy system

The rotational atherectomy procedure offers a fast and efficient treatment method with regard to stenoses of the vascular system.

Atherectomy is a minimally invasive procedure in which coronary and peripheral arterial occlusions are treated mechanically with minimal surgical effort. This includes the removal of plaque and calcium deposits that can occur in the context of vascular disease. "Mechanical treatment" in this case defines the dilatation (widening) of the vessel lumen without damaging the vessel wall through overstretching or injury [01-03].

Compared to balloon angioplasty, rotational atherectomy is a procedure that puts less stress on the vessel wall. Here, the occlusion material is "milled out" and not compressed against the vessel wall [04].

In the project funded by the Senate Commission for Studies and Teaching (K1), the students have now developed a demonstration model of a jetstream rotational atherectomy system.

The interdisciplinary approach of the project was interesting, as mechanical engineering, electrical engineering and physiological issues had to be dealt with.

The demonstration model focuses on visualising the treatment method, with students learning about the structure and functions of the catheter system. Individual groups of students worked on the tasks in the various processing areas and, in consultation with each other, created a concept for the development of the model, which then formed the basis for practical implementation. With regard to the model, questions about flow behaviour within the vascular system with regard to stenoses and the necessity of biocompatibility of such medical devices could be discussed.

The demonstration model serves the purpose of demonstration in courses and practical trainings. In addition, the system can be continued in the future as part of student final theses and mini-projects.

Within the scope of the student project, a functional demonstration model of a rotational atherectomy system could be developed. One of the focal points was the visualisation of the treatment method, for which a suitable scale of 20:1 was chosen for the model. The structure and functions of the catheter system can thus be analysed in detail. The cooperation of the students among each other was promoted by the project, which was finally also evident in the assembly of the various components of the model, which are optimally coordinated with each other. However, there is still a need for optimisation with regard to the replacement material for the stenosis.

The demonstration model is to be used in the courses and lectures as early as next semester. Instructions for using the model in practical training are still being worked on. Flow investigations with the help of the PIV system (Particle Image Velocimetry) available in the laboratory are also planned in order to improve the flushing system, i.e. the outflow of the dissolved particles.