Academic chairs
Medical engineering, fluid mechanics, materials engineering, cardiovascular technology — with an existing circulatory or endurance test bench.
Seeking laboratory access for the next validation stage.
Over several years, design work, manufactured modules and a circulation test rig have been built. The next step needs an environment that cannot be created privately — and partners who can work with blood, circulation and measurement technology.
Project status
What exists
Three modules exist as manufactured hardware of the earlier architecture stage: the pulsatile membrane chamber for the systemic circuit, the micro-axial pump for the pulmonary circuit and the pulse chamber. They were produced additively, from standard components and by hand.
A circulatory test bench is built and in operation. It has circulated fluid at blood-like viscosity. The sensing — flow, pressure and oxygenation, on both sides and before and after each inlet, plus preload and afterload — is installed.
The current architecture exists as design work and concept calculation; energy storage, battery management and inductive charging as concept, not as hardware.
Rationale
Why pulsatile
Current support systems mostly use rotary pumps at several thousand revolutions per minute. Reduced pulsatility there is associated with acquired von Willebrand syndrome, bleeding from arteriovenous malformations and aortic insufficiency; the cause is destruction of high-molecular-weight von Willebrand multimers by shear.
A displacement pump, by contrast, works at about one to two strokes per second — orders of magnitude fewer cycles and correspondingly lower shear. That is a design rationale, not a claim of efficacy.
Pulsatility also matters for the pulmonary circuit: in the Fontan and Glenn circulation, where the lung is perfused without pulsation, impaired endothelial function, reduced nitric oxide availability and rising pulmonary vascular resistance are documented.
Needs
What is being sought
The next development step is a measurement series using animal blood: behaviour under real viscosity and cellular loading rather than model fluid. Laboratory access and a measurement environment are what is missing.
- Access to a circulatory test bench or perfusion laboratory
- The ability to work with animal blood — anticoagulation, cold chain, proper disposal
- Time-resolved flow measurement, so that pressure and flow can be evaluated together
- Specialist guidance on haemocompatibility and flow measurement
- Membrane materials and endurance testing
- In due course: flow simulation and standards-compliant testing
With access in place, six to eighteen months to meaningful data is a realistic horizon.
Research questions
Three open questions to work on
All three are bounded and not conclusively answered in the literature.
- Which ejection profile gives a pulmonary pulse maximum surplus haemodynamic energy without raising mean pulmonary arterial pressure above 20 mmHg?
The pulmonary circuit leaves only a few mmHg of headroom before benefit turns into harm.
- At what stroke volume does pulmonary pulsatility become physiologically effective?
No threshold is defined in the literature. Pulsatile cardiopulmonary bypass, at roughly 5,000 ergs/cm³ at the patient, serves as the reference figure.
- What ramp limit keeps the output control loop outside the baroreflex time constant without delaying demand response?
Pump and body are two controllers acting on the same plant; overlapping time constants lead to hunting.
For clinicians
Four questions for cardiology and cardiac surgery
Only clinical experience can answer these questions. A short expert opinion would move the development forward considerably.
- Which flows and pressures must a total artificial heart deliver from rest to exertion, and where are the clinically most important lower limits?
For example during sleep, with fever or with raised pulmonary vascular resistance.
- Which space constraints and vessel connections in the chest are critical in daily practice with existing systems?
Fit is a goal of the project but not yet verified against imaging data.
- Which complications of today's systems should a new concept avoid most urgently?
Bleeding, thrombosis, infection, device failures: how would they be weighted?
- What should an alarm look like that reliably reaches patients even during sleep?
And who should receive it first: the patient, the clinic or a control centre?
Audiences
Who this is addressed to
Doctoral researchers
Anyone looking for a bounded, practically workable question for their own research.
Perfusion and cardiovascular technology
Practitioners with daily experience of extracorporeal circulation, pumps and blood.
Manufacturers
Medical device and drive-technology companies with their own development and testing infrastructure.
Contribution
What the project brings
- Several years of groundwork.
Design, dimensioning, manufactured modules, installed sensing and a circulatory test bench. A partner does not start from zero.
- Co-authorship.
Results from joint work are published jointly.
- Clear agreements.
Use and publication of joint results are agreed in advance.
Open points
What is missing, stated explicitly
- No flow simulation performed; structural simulation scheduled in the work planOpen
- No work to ISO 14971, IEC 60601 or ISO 5840 so farOpen
- Volumetric flow calculated and not validatedOpen
- No time-resolved flow measurement, therefore no energy-based assessment of pulsatilityOpen
- No blood testing, no haemolysis dataOpen
- Values of the current architecture not yet CAD/FE-verifiedOpen
- Energy storage, battery management and inductive charging only as a conceptOpen
- No institutional affiliation, no third-party fundingOpen
Contact
For technical enquiries, a direct message to info@kanzlerbiologicals.com is sufficient. Responses that contradict the project are equally welcome — a well-founded objection is worth more than agreement.