Abstract: A portable machine for recording electrocardiographic signals from a patient, the machine having a recording device for collecting electrocardiographic signals from a patient, the recording device further including a removable memory device for storing the electrocardiographic signals, a remote programming device including a remote connection with said recording device for wireless communication therewith, and patient lead wires with electrodes constructed and arranged to attach to the skin of the patient to furnish the electrocardiographic signals to said recording device.

Abstract: In one aspect, the invention is a method for processing pulse oxymetry data signals. The method includes recording pulse oxymetry data signals. The pulse oxymetry data signals have a plurality of oxymetry waveforms. The method also includes determining a correlation coefficient between sequential oxymetry waveforms and identifying a valid pulse oxymetry waveform.

Abstract: In one aspect, the invention is a method for processing pulse oxymetry data signals. The method includes recording pulse oxymetry data signals. The pulse oxymetry data signals have a plurality of oxymetry waveforms. The method also includes determining a correlation coefficient between sequential oxymetry waveforms and identifying a valid pulse oxymetry waveform.

Abstract: In general, the invention is directed to techniques for using a magnet to suspend a function of an implanted device, and to verify that the function has been suspended. A suspension device emits a magnetic field to suspend a function of a device implanted in a body, receives a signal that the function has been suspended, and outputs an indicator that the function has been suspended. In this manner, an operator can proceed having confidence that the suspension of the function was completed, and did not fail due to inappropriate placement of the magnet, slippage, or any other of a number of reasons.

Abstract: A portable machine records electrocardiographic signals and oxygen saturation signals in a removable memory device provided by an oxygen saturation sensor attached to a patient and patient lead wires with electrodes attached to the patient.

Abstract: An impedance measurement system for electrocardiographic recorders which allows measurement of the electrode channel impedance without the need for a separate piece of equipment. The impedance measurement system, which is an integral part of the recorder, applies complementary oscillating currents having short transition times to an electrode channel defined by a pair of electrode leads, a pair of electrodes and the patient tissues. The analog current signals flowing through the electrode channel create a voltage across the electrode channel which is amplified and applied to a dual range filtering stage. The low range section of the dual range filtering stage generates a time-dependent signal which causes the output of the low range filtering circuit to produce a signal applied to the timing input of a microprocessor. The microprocessor calculates the time elapsed between each transition of the oscillating current signals and the occurrence of a signal at the output of the low range filtering circuitry.

Abstract: A method and apparatus for digitally storing episodic signals, such as, electrocardiogram signals is disclosed. In a preferred embodiment, the apparatus includes, for each signal channel, an input amplifier, an analog-to-digital converter, and a double data buffer. The incoming signal on each channel is converted to a multibit digital number a fixed sampling rate. Each multibit digital number is stored in a location in the double data buffer. When a fixed amount of data is stored in the buffer, a processor examines the data to determine the periods during which the signal is undergoing the most rapid rate of change. For these periods, both an indicator of the period, and a first number of data samples per unit time is stored in a bulk solid state memory. Preferably, the data stored is a number relating to the difference between the value of the sample and a number related to the value of the last sample.

Abstract: In an electrocardiographic system there is a multielement electrode at two skin locations for providing an ECG signal of negligible magnitude between elements because of the close spacing while the pair of elements are sufficiently separated so that the motion of one element is at least partially independent of the motion of the other. Parallel ECG signals are obtained from different elements of two multielement electrodes. The difference between the signals is detected by logical circuitry to produce a signal indicating baseline shift.

Abstract: In an electrocardiographic system there is a multielement electrode at each skin location for providing an ECG signal of negligible magnitude between elements because of the close spacing while the pair of elements are sufficiently separated so that the motion of one element is at least partially independent of the motion of the other; thus, events causing a baseline shift will also cause a difference in potential between the two elements of a multielement electrode. That difference is detected by logical circuitry to produce a signal indicating baseline shift.