Fecha de publicación: 24/05/2007 Fuente: Wipo "Sensorization" A sensor 20 is disclosed, for implantation within a blood vessel to monitor a substance in or property of blood. In one embodiment, the sensor 20 detects nitric oxide or a nitric oxide metabolite. In another embodiment, other substances such as glutamate, aspartate, arginine, citralline, acetylcholine, calcium, potassium, or dopamine are monitored. The sensor may be attached to a support structure such as a stent, guidewire, or catheter 500. In a further embodiment, a catheter 500 is disclosed that extracts patient fluid to a sensor outside the body for monitoring a substance or property of the patient fluid.