Arterial strain measurement by implantable capacitive sensor without vessel constriction.
Cardiovascular disease caused 32.8% of deaths in the United States in 2008 [1]. The most important medical parameter is the arterial blood pressure. The origin of high or low blood pressure can mostly be found in the vessel compliance. With the presented implantable sensor, we are able to directly measure strain of arteries, as an indicator of arteriosclerosis. The sensor is designed as a cuff with integrated capacitive structures and is wrapped around arteries. With a new and innovative locking method, we could show that the system does not affect the arteries. This is demonstrated by theory as well as experimental in vivo investigations. Biocompatibility tests, confirmed by histological cuts and MRI measurements, showed that no stenosis, allergic reactions or inflammation occurs. The sensor shows excellent linear behavior with respect to stress and strain.
Department of Microsystems Engineering (IMTEK), University of Freiburg, Georges-Koehler-Allee 102, 79110 Freiburg, Germany. Johannes.Ruhhammer@imtek.uni-freiburg.de
Johannes
J
Ruhhammer
Dominic
D
Ruh
Katharina
K
Foerster
Claudia
C
Heilmann
Friedhelm
F
Beyersdorf
Alex
A
Barker
Bernd
B
Jung
Andreas
A
Seifert
Frank
F
Goldschmidtboeing
Peter
P
Woias
D000818:Animals; D062186:Arterial Pressure / Q000502:physiology; D001158:Arteries / Q000502:physiology*; D001161:Arteriosclerosis / Q000175:diagnosis / Q000503:physiopathology; D001795:Blood Pressure Determination / Q000295:instrumentation; D003187:Compliance / Q000502:physiology; D004867:Equipment Design; D005263:Femoral Artery / Q000502:physiology; D006801:Humans; D018810:Magnetic Resonance Angiography; D008955:Models, Cardiovascular; D019736:Prostheses and Implants; D012828:Silicones; D034421:Sus scrofa; D018924:Vascular Capacitance / Q000502:physiology*
D012828:Silicones