This invention describes a method for processing pressure signals derivable from locations inside or outside a human or animal body or body cavity. Different aspects of the invention relate to a method for optimal differentiating between cardiac beat- and artifact-induced pressure waves, a method for obtaining new and improved information from said pressure signals, a method for obtaining signals predicting pressures inside a body or body cavity from pressure signals outside said body or body cavity. In particular, this invention describes devices for sensing continuous pressures signals and displaying otput of processing according to the inventive methods.