A cryocatheter for treating cardiac arrhythmias comprises a miniature refrigeration system powered by electromagnetic radiation. Leveling strips are provided along mounted surfaces of the frame to support the plates, piston-and-cylinder units and the like serving to press the mats of wood material. The present invention furthermore provides a method of producing the prodrugs, to enhance brain and lymphatic delivery of drugs andor to extend drug half-lives in plasma. The system then enables querying of the data segment and a set of offline data segments comprising older records of the one or more metrics and the at least one dimension. Wherein the armature is coupled to, or forms part of, the valve such that controlled energisation of the electromagnet causes the armature to be either attracted to or repelled from the piece of magnetisable material one or more times to operate the valve for a controlled time period to effect dispensation of a metered dose of pressurised product from the reservoir through the valve outlet.