A smartphone-enabled wireless and batteryless implantable blood flow sensor for remote monitoring of prosthetic heart valve function

Autoři: Bernhard Vennemann aff001;  Dominik Obrist aff002;  Thomas Rösgen aff001
Působiště autorů: Institute of Fluid Dynamics, ETH Zürich, Zürich, Switzerland aff001;  ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland aff002
Vyšlo v časopise: PLoS ONE 15(1)
Kategorie: Research Article
doi: https://doi.org/10.1371/journal.pone.0227372


Aortic valve disease is one of the leading forms of complications in the cardiovascular system. The failing native aortic valve is routinely surgically replaced with a bioprosthesis. However, insufficient durability of bioprosthetic heart valves often requires reintervention. Valve degradation can be assessed by an analysis of the blood flow characteristics downstream of the valve. This is cost and labor intensive using clinical methodologies and is performed infrequently. The integration of consumer smartphones and implantable blood flow sensors into the data acquisition chain facilitates remote management of patients that is not limited by access to clinical facilities. This article describes the characteristics of an implantable magnetic blood flow sensor which was optimized for small size and low power consumption to allow for batteryless operation. The data is wirelessly transmitted to the patient’s smartphone for in-depth processing. Tests using three different experimental setups confirmed that wireless and batteryless blood flow recording using a magnetic flow meter technique is feasible and that the sensor system is capable of monitoring the characteristic flow downstream of the valve.

Klíčová slova:

Blood flow – Cell phones – Magnetic fields – Magnets – Medical implants – Prototypes – Signal processing – Electronic circuits


1. Head SJ, Çelik M, Kappetein AP. Mechanical versus bioprosthetic aortic valve replacement. Eur Heart J. 2017 Jul;38(28):2183–91. doi: 10.1093/eurheartj/ehx141 28444168

2. Nishimura RA. Aortic Valve Disease. Circulation. 2002 Aug;106(7):770–2. doi: 10.1161/01.cir.0000027621.26167.5e 12176943

3. Vesely I. The evolution of bioprosthetic heart valve design and its impact on durability. Cardiovasc Pathol. 2003 Sep-Oct;12(5):277–286. doi: 10.1016/s1054-8807(03)00075-9 14507578

4. Grunkenmeier G, Jamieson W, Miller D, Starr A. Actuarial versus actual risk of porcine structural valve deterioration. J Thorac Cardiovasc Surg. 1994 Oct;108(4):709–18. doi: 10.1016/S0022-5223(94)70298-5

5. Vilkomerson D, Chilipka T. Implantable doppler system for self-monitoring vascular grafts. IEEE Ultrasonics Symposium. 2005 461–5.

6. Vilkomerson D, Chilipka T, Bogan J, Blebea J, Choudry R, Wang J, et al. Implantable ultrasound devices. Medical Imaging 2008: Ultrasonic Imaging and Signal Processing. 2008 Mar.

7. Cannata JM, Chilipka T, Yang HC, Han S, Ham SW, Rowe VL, et al. Development of a flexible implantable sensor for postoperative monitoring of blood flow. J Ultrasound Med. 2012 Nov;31:1795–1802. doi: 10.7863/jum.2012.31.11.1795 23091251

8. Tang SC, Vilkomerson D, Chilipka T. Magnetically-powered implantable Doppler blood flow meter. IEEE International Ultrasonics Symposium, IUS. 2014.

9. Unadkat J, Rothfuss M, Mickle MH, Sejdic E, Gimbel M. Entirely Implanted Wireless Doppler Sensor for Monitoring Venous Flow. Plast Reconstr Surg. 2014 Oct;134(4S-1):57–58. doi: 10.1097/01.prs.0000455398.99175.a6

10. Unadkat JV., Rothfuss M, Mickle MH, Sejdic E, Gimbel ML. The Development of a Wireless Implantable Blood Flow Monitor. Plast Reconstr Surg. 2015 Jul;136(1):199–203. doi: 10.1097/PRS.0000000000001372 26111323

11. Rothfuss MA, Franconi NG, Unadkat JV, Gimbel ML, Star A, Mickle MH, et al. A System for Simple Real-Time Anastomotic Failure Detection and Wireless Blood Flow Monitoring in the Lower Limbs. IEEE J Transl Eng Heal Med. 2016. doi: 10.1109/JTEHM.2016.2588504

12. Cheong JH, Ng SSY, Liu X, Xue RF, Lim HJ, Khannur PB, et al. An inductively powered implantable blood flow sensor microsystem for vascular grafts. IEEE Trans Biomed Eng. 2012 Sep;59(9):2466–2475. doi: 10.1109/TBME.2012.2203131 22692871

13. Boutry CM, Beker L, Kaizawa Y, Vassos C, Tran H, Hinckley AC, et al. Biodegradable and flexible arterial-pulse sensor for the wireless monitoring of blood flow. Nat Biomed Eng. 2019 Jan;3:47–57. doi: 10.1038/s41551-018-0336-5 30932072

14. Majerus SJA, Chong H, Ariando D, Swingle C, Potkay J, Bogie K, et al. Vascular Graft Pressure-Flow Monitoring Using 3D Printed MWCNT-PDMS Strain Sensors. Proc Ann Int Conf IEEE Eng Med Biol Soc, EMBS. 2018.

15. Steeves CA, Young YL, Liu Z, Bapat A, Bhalerao K, Soboyejo ABO, et al. Membrane thickness design of implantable bio-MEMS sensors for the in-situ monitoring of blood flow. J Mat Sci: Mat in Med. 2007 Jan;18(1):25–37.

16. Xue RF, Cheong JH, Cha HK, Liu X, Li P, Lim HJ, et al. Ultra-low-power wireless implantable blood flow sensing microsystem for vascular graft applications. Int Sym Int Cir, ISIC 2011.

17. Mills CJ. Measurement of pulsatile flow and flow velocity. Academic press. 1972.

18. Locke SE, Gale TJ, Kilpatrick D. Development of an implantable blood flow and pressure monitor for pulmonary hypertension. Comput in Cardiol. 2004 Sep;713–6.

19. Mallinson JC. One sided fluxes—a magnetic curiosity IEEE Trans on magnetics. 1973 9(4):678–682. doi: 10.1109/TMAG.1973.1067714

20. Halbach K. Design of permanent multipole magnets with ori- ented rare earth cobalt material. Nucl instr and methods. 1980 169(1):1–10. doi: 10.1016/0029-554X(80)90094-4

21. Kolin A. Electromagnetic recording flowmeter. Am J of Physiol. 1937 119:355–356.

22. Wetterer E. Der induktionstachograph. Zeitschr fur Biol. 1938 99:158–162.

23. Shercliff JA. The theory of electromagnetic flow-measurement. Cambridge university press. 1962.

24. Woodcock JP. Theory and practice of blood flow measurement London Butterworths. 1975.

25. Raich H, Blümler P. Design and construction of a dipolar Halbach array with a homogeneous field from identical bar magnets: NMR Mandhalas. Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering. 2004 23B(1):16–25. doi: 10.1002/cmr.b.20018

26. Windt CW, Soltner H, Van Dusschoten D, Blümler P. A portable Halbach magnet that can be opened and closed without force: The NMR-CUFF. J Magn Reson. 2011 Jan;208(1):27–33. doi: 10.1016/j.jmr.2010.09.020 21036637

27. Vennemann B. Wireless blood flow sensing for automated diagnostics ETH Research Collection. 2019.

28. Vennemann B, Obrist D, Rösgen T. Automated diagnosis of heart valve degradation using novelty detection algorithms and machine learning. PLoS One. 2019 Sep;14(9):e0222983. doi: 10.1371/journal.pone.0222983 31557196

29. Furlani EP. Permanent magnet and electromechanical devices. Materials, analysis and applications. Academic press 2001.

30. Schwan HP. Electrical properties of blood and its constituents: alternating current spectroscopy. Blut. 1983 Apr;46(4):185–97. doi: 10.1007/bf00320638 6338980

31. Zijlstra H. Permanent magnet systems for NMR tomography. Phillips J Res. 1985 40(5):259–288.

32. Vennemann B, Rösgen T, Heinisch PP, Obrist D. Leaflet kinematics of mechanical and bioprosthetic aortic valve prostheses. ASAIO J. 2018 Sep/Oct;64(5):651–661. doi: 10.1097/MAT.0000000000000687 29045279

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2020 Číslo 1
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