This graduation thesis investigated how high-risk Class III medical devices can move from the linear “take–make–use–incinerate” model towards circular interventions. The case study was the Transcatheter Aortic Valve Implantation (TAVI) procedure, a minimally invasive intervention for patients with severe aortic stenosis. The main focus was the TAVI delivery system, the medical device used to implant prosthetic aortic heart valves via a catheter. The TAVI delivery system is used for approximately one hour, then discarded as hazardous waste, meaning it is incinerated at high temperature. The medical device contains high-grade polymers, base metals, and precious metals, which are destroyed after a single use.

To address this, the project identified a realistic entry point for circularity in high-risk medical devices that maintains patient safety, regulatory compliance, and clinical workflows. Achieving this required not just product design but a systems-thinking approach. For instance, even if the TAVI delivery system is redesigned, circularity cannot be achieved without a supporting collection system, regulatory alignment, and clear stakeholder responsibilities.

Building on this need for a systems approach, the research addressed the transition across four healthcare levels. These levels were defined through adapting the Multilevel Design Model (MLDM) and translating it to healthcare. The translated MLDM structured both the diagnostic analysis and the development of coordinated transition pathways. The four levels are:
1. Society: healthcare context (regulation and policies);
2. Healthcare system (logistics, infrastructure and collaboration);
3. Clinical workflow (clinical routines and behaviour);
4. Medical device (product architecture and material composition).

The MLDM was used to identify environmental hotspots, barriers and opportunities.
Based on this analysis, four circular design directions were developed by evaluating R-strategies for the TAVI delivery system, loading system, and packaging. Reuse, recycle, rethink and reduce were selected across these TAVI products. They were compared on environmental impact, implementation barriers, required product redesign, and workflow disruptions. Recycling the TAVI delivery system was selected as the solution direction.

Recycling the TAVI delivery system was identified as a strategic entry point, serving as a midway point for feasibility and impact. Next, the recycling barriers were identified as linear waste infrastructure, misaligned incentives, fragmented ownership, product design constraints, and workflow time pressure. These barriers were translated into design criteria and required system shifts across the four levels of healthcare.

The main outcome of this thesis is a system-embedded recycling framework for high-risk medical devices, demonstrated with the TAVI delivery system. The framework outlines six steps to create coordinated, controlled recycling pathways. It consists of:
1. Defining stakeholder motivation;
2. Selecting target materials to recycle;
3. Define technical and operational recycling process steps;
4. Assign roles and responsibilities;
5. Create recycling pathways;
6. Select intervention and product design proposals.

Original Equipment Manufacturers (OEMs) are positioned as initiators because product architecture makes recycling pathways technically feasible. Implementation still depends on OEMs, hospitals, and recyclers working together.

The framework is presented in a stakeholder-focused booklet that serves as both a practical guide and a call to action to initiate coordinated recycling pathways. To demonstrate it, the framework was applied to two recycling pathways for TAVI delivery systems. Pathway 1, centred on precious metal recycling, provides a short-term, low-operational burden option targeting high material value. Pathway 2 addresses polymer recycling and represents a medium-term, higher operational burden, targeting high volume. This pathway requires design-for-recycling strategies to be implementable. Collectively, the recycling pathways illustrate how concrete steps and assigned responsibilities can set the stage for strengthening circular strategies within healthcare.

Using the translated MLDM, the transition from the incineration default in the linear system to coordinated recycling pathways was structured. This was done across the four healthcare levels and four design phases. This model demonstrates how aligned interventions across society, healthcare systems, clinical workflows, and medical device design enable circular implementation for high-risk medical devices.

This research demonstrates that advancing circularity for high-risk medical devices requires alignment of people, processes, and technology. Incineration remains the default not just because of its complex design, but also because healthcare systems prioritise speed, sterility, and liability reduction. This thesis introduces recycling as a coordinated pathway at multiple system levels. It offers a structured framework for circular healthcare. Finally, it demonstrates how high-risk devices can move from hazardous waste to controlled recycling without compromising clinical performance or safety. ... Read more