Abstract: An implantable lead which has an increased resistance to fracture and has the capability of continued function after fracture of a conductor. The lead is provided with a coiled conductor which may be monofilar or multifilar and which extends along the length of the lead, running from an electrical connector at the proximal end of the lead to an electrode at or near the distal end of the lead. In addition, the lead is provided with a stranded conductor which is electrically coupled to the coiled conductor at point along the lead body located proximal to the point of expected breakage of the coiled conductor and at a point along the lead body located distal to the point of expected breakage. The proximal and distal ends of the stranded conductor in some embodiments are also mechanically coupled to the coiled conductor.

Abstract: Multi-site cardiac pacing systems for providing pacing to multiple spaced apart sites of a patient's heart, including especially but not limited to sites in right heart chamber (RHC) and left heart chamber (LHC), in triggered pacing modes while avoiding inappropriate delivery of triggered pacing to the RHC and/or LHC on a non-refractory sense event that occurs early in the cardiac cycle.

Abstract: Apparatus and method for obtaining from a patient's heart data useful for on-line setting of the parameters of a detection time window in an excitable tissue control device. The method includes applying electrodes to a first cardiac site and a second cardiac site of a patient and electrically connecting the electrodes to a data collecting device. The device is then operated under a plurality of different cardiac conditions to obtain a plurality of different histogram data sets. Each histogram data set represents a cumulative time distribution histogram of cardiac depolarization events detected at the second cardiac site in a plurality of cardiac beats. Each histogram data set is defined by a plurality of histogram parameters having values indicative of the cardiac conditions common to the plurality of cardiac beats used to obtain the histogram data set.

Abstract: A hydrodynamic blood bearing includes a piston disposed coaxially in a housing bore. The piston includes a cylindrical outer surface journal spaced from the bore to define a first radial gap for receiving blood as a bearing fluid for hydrodynamically supporting the piston. The piston includes two sets of bearing pads axially spaced apart from each other, with each set including circumferentially spaced apart pads for increasing tilt stiffness of the bearing defined by the journal.

Abstract: An implantable cardiac stimulation device including an activity/position sensor that incorporates a magnetoresistive sensor and a magnet that are positioned so as to move relative to each other in response to activity and the body position of the patient when the device is implanted in the body of the patient. In one embodiment, the sensor includes a magnetoresistive sensor that is made from giant magnetoresistive (GMR) materials. Preferably, a magnet is positioned on a flexible cantilevered beam so as to be positioned adjacent the magnetoresistive sensor. Movement of the patient results in relative movement of the magnet with respect to the magnetoresistive sensor and generates a signal having an AC component corresponding to a patient's activity and a DC component corresponding to the patient's body position.

Abstract: A cardiac rhythm management system includes techniques for computing an indicated pacing interval, AV delay, or other timing interval. In one embodiment, a variable indicated pacing interval is computed based at least in part on an underlying intrinsic heart rate. The indicated pacing interval is used to time the delivery of biventricular coordination therapy even when ventricular heart rates are irregular, such as in the presence of atrial fibrillation. In another embodiment, a variable filter indicated AV interval is computed based at least in part on an underlying intrinsic AV interval. The indicated AV interval is used to time the delivery of atrial tracking biventricular coordination therapy when atrial heart rhythms are not arrhythmic. Other indicated timing intervals may be similarly determined. The indicated pacing interval, AV delay, or other timing interval can also be used in combination with a sensor indicated rate indicator.

Abstract: A method and design is provided for distributing and storing sets of temporally ordered information in a systematic and sequential fashion. This method is based on a model of how the brain functions in the distribution and storage of temporally ordered memories, but it can also be applied to the design of new biological, electronic or optical devices. These devices may be used in the testing and development of new therapeutic drugs, in the detection of toxic agents or impaired performance, or in the development of new industrial and consumer devices in which the orderly storage of sequential information is important.

Abstract: Temperature in frozen tissue can be measured from magnetic resonance signals from the frozen tissue based on spin-spin relaxation time (T2) or based on relative intensity of the magnetic resonance signals. Short echo times are required, and use of tailored RF pulses, non-Cartesian readouts, and multi-slice and 3D k-space acquisitions are preferably employed.