A non-invasive venous pressure measurement apparatus is provided, including: a first cuff attached to a portion including a vein and an artery in a living body; a pressure control unit that changes a first applied pressure applied by the cuff to the portion; a pulse wave detection unit that detects a pulse wave from a pressure received by the cuff from the portion; another pulse wave detection unit that detects another pulse wave including at least an arterial pulse wave in another portion of the living body; an analyzing unit that analyzes a correlation between the two pulse waves, which are changed as the applied pressure is changed by the pressure control unit changes; and a venous pressure calculation unit that calculates a venous pressure based on the applied pressure and a result of analysis by the analyzing unit.

A method includes, in a living organ (28) in which an ambient pressure varies as a function of time, sensing the ambient pressure using a pressure sensor (36, 90, 174), which has a capacitance that varies in response to the ambient pressure, so as to produce a time-varying waveform. A calibration voltage, which modifies the capacitance and thus the time-varying waveform, is applied to the pressure sensor. The time-varying waveform is processed so as to isolate and measure a contribution of the calibration voltage to the waveform. A dependence of the capacitance on the ambient pressure is calibrated using the measured contribution of the calibration voltage.

The systems and methods described herein determine metrics of cardiac or vascular performance, such as cardiac output, and can use the metrics to determine appropriate levels of mechanical circulatory support to be provided to the patient. The systems and methods described determine cardiac performance by determining aortic pressure measurements (or other physiologic measurements) within a single heartbeat or across multiple heartbeats and using such measurements in conjunction with flow estimations or flow measurements made during the single heartbeat or multiple heartbeats to determine the cardiac performance, including determining the cardiac output. By utilizing a mechanical circulatory support system placed within the vasculature, the need to place a separate measurement device within a patient is reduced or eliminated. The system and methods described herein may characterize cardiac performance without altering the operation of the heart pump (e.g., without increasing or decreasing pump speed).

A time-resolved measurement of blood pressure, arterial elasticity, pulse wave, pulse wave transit time and pulse wave velocity, a cardiac output, and/or changes in cardiac output of a human or animal body, using a pressure sensor unit while being pressed against the skin. The unit is an air and/or gas pressure sensor, and is configured to change at least one electrical conductance and/or resistance when subjected to pressure. The unit has at least two conductor trace arrays, particularly conductor trace networks, and a functional polymer that is compressed when subjected to pressure, and produces and/or alters contact between the conductor trace arrays. Alternatively, the unit has at least two conductive layers with a gap therebetween, and is configured such that the gap becomes compressed when subjected to pressure, and/or such that the capacitance of the assembly composed of the two conductive layers is changed as a result.

Provided is a film-type biomedical signal measuring apparatus configured in a such a way that a plurality of metallic thin film electrodes and a circuit unit are formed on a film-type piezoelectric element so as to easily attach the apparatus to the skin and an electrical signal as well as an electrical signal of a human body is simultaneously measured using the plurality of metallic thin film electrodes and the circuit unit. Accordingly, the film-type biomedical signal measuring apparatus simultaneously measures electrocardiogram (ECG) and ballistocardiogram (BCG) from the simultaneously measured electrical signal and vibration signal of the human body and extracts biomedical information of various types of health indexes such as a heart rate, a stress index, BCG, a blood pressure, an amount of physical activity, a respiration rate, and VO.sub.2max from the two different biomedical signals.

A venous pressure measurement apparatus includes: a pressure controller that causes an internal pressure of a cuff to he attached to a subject, to change; a pressure detector that detects the internal pressure of the cuff; and a processor that causes the pressure controller to change the internal pressure of the cuff, acquires a statistical value relating to a distribution of amplitudes of a plurality of pressure changes corresponding to pressure vibration that occurs in the cuff, and that is detected by the pressure detector, and estimates a venous pressure of the subject based on a change of the statistical value due to the change of the internal pressure of the cuff.

Examples of portable electronic devices including a piezo actuated vibrator for providing tactile feedback to the user are described. Portable electronic devices according to the present disclosure may include tactile feedback devices, which may be driven by a piezoelectric actuator/vibrator that is operatively coupled to or embedded into the housing of a portable electronic device. In some examples, the housing of the electronic device itself can be made of piezoelectric ceramic material. The piezoelectric element may be coupled to the housing of the product to cause the housing to deflect and/or vibrate. In some examples, the housing of the portable electronic device, which may be a portable media player device, may be configured for placement directly or indirectly in contact with the user's skin such that vibrations of the housing may be felt directly (without audible feedback) by the user.

The systems and methods described herein determine metrics of cardiac performance via a mechanical circulatory support device and use the cardiac performance to calibrate, control and deliver mechanical circulatory support for the heart. The systems include a controller configured to operate the device, receive inputs indicative of device operating conditions and hemodynamic parameters, and determine vascular performance, including vascular resistance and compliance, and native cardiac output. The systems and methods operate by using the mechanical circulatory support device (e.g., a heart pump) to introduce controlled perturbations of the vascular system and, in response, determine heart parameters such as stroke volume, vascular resistance and compliance, left ventricular end diastolic pressure, and ultimately determine native cardiac output.

A blood pressure detection method is used for the sphygmomanometer including an envelope, an air pressure control mechanism, an ultrasonic wave transmission mechanism and an ultrasonic wave reception mechanism. The blood pressure detection method includes: applying a control signal to the air pressure control mechanism and the ultrasonic wave transmission mechanism, to inflate and deflate the envelope, and enable the ultrasonic wave transmission mechanism to transmit an ultrasonic detection signal toward the to-be-detected body part at a predetermined interval; monitoring an ultrasonic reflection signal received by the ultrasonic wave reception mechanism; determining a detection time point for the blood pressure detection in accordance with a frequency of the ultrasonic reflection signal during the deflation of the envelope; and determining a blood pressure value for the blood pressure detection in accordance with a pressure value of air within the envelope at the detection time point.

The object of the present invention is to disclose a novel optical miniaturized handheld medical device for convenient monitoring and/or data collection of detailed signals on human cardiovascular function. The implementation consists of a number of advanced technologies, including interferometric detection, phase controlled focusing beam steering, auto-tracking scheme and algorism, and integrated optical chip assembly to enhance the device's performance and miniaturization. Briefly, this handheld medical device directs a single or dual output laser beam(s) onto certain skin surface to detect the surface vibration velocity at the point where the laser hits the surface. The skin surface vibrates in response to cardiovascular signals, such as blood pressure pulses, turbulent blood flow through narrowed arteries, pumping actions of the heart, or the closure of the heart valves etc. The miniaturized apparatus thus is capable of detecting these signals for the assessment of cardiovascular functions in both healthy and disease conditions.