A catheter system including an accelerometer-based sensing assembly is provided. In particular the present teachings relate to an accelerometer based assembly used to determine contact between a catheter and surrounding proximate tissue, such as cardiac tissue. An embodiment of such a system may, for example, be used for visualization, mapping, ablation, or other methods of diagnosis and treatment of tissue and/or surrounding areas.

A medical device and associated method record signals from each real axis of a multi-axis sensor. An optimal axis for monitoring a physiological signal of the patient is identified from the real axes of the multi-axis sensor and multiple virtual axes. Coordinates defining the optimal axis are stored as respective weighting factors of the signals from each real axis of the multi-axis sensor. A metric of the physiological signal is determined using the multi-axis sensor signals and the weighting factors.

An ICD multimode system comprises a microcontroller or FPGA having a memory, a differentially driven phased array amplifier, one or more sensors, and a wireless transmitter/receiver. Based upon sensor data and demand criteria programmed into the memory, the system provides late systolic impulse (LSI) therapy to treat congestive heart failure (CHF), ventricle level-shifting (VLS) therapy to block unwanted PVCs to prevent VT or VF, and cardiac resynchronization therapy (CRT) that adjusts LV and RV contraction synchronization based upon timing. An integrated echocardiogram and ultrasound system automatically adjusts the therapies administered based upon sensor and demand data in real time to allow a patient's heart to function at a level of improved performance and efficiency.

Methods and apparatuses for use in medical procedures are disclosed. Some implementations may include a medical procedure guide that can overlay portions of anatomy of a patient. The guide may include alignment markings to facilitate proper placement, procedure markings to facilitate determination of a position at which to commence a medical procedure, and/or imaging markers incorporated within the guide to facilitate commencement or completion of the medical procedure in conjunction with imaging.

Method and system for determining an atrial contraction timing fiducial in a leadless cardiac pacemaker system is disclosed. An electrical cardiac signal associated with an atrial contraction of the patient's heart and a mechanical response to the atrial contraction of a patient's heart are used to determine an atrial contraction timing fiducial. A ventricle pacing pulse may then be generated an A-V delay after the atrial contraction timing fiducial.

A medical device is configured to produce a cardiac motion signal by sampling a signal produced by an axis of a motion sensor, starting a blanking period, suspending the sampling of the signal during at least a portion of the blanking period, and restarting the sampling of the signal at the sampling frequency before the blanking period has expired. The medical device may detect a cardiac event from the cardiac motion signal and generate a pacing pulse in response to detecting the cardiac event in some examples.

Systems and methods for ambulatory detection of medical events such as cardiac arrhythmia are described herein. An embodiment of an arrhythmia detection system may include a detection criterion circuit that determines a patient-specific detection criterion using a baseline cardiac characteristic when the patient is free of cardiac arrhythmias. The detection criterion circuit generates a patient-specific threshold of a signal metric by adjusting a population-based threshold of the signal metric, where the manner and the amount of adjustment is based on information about patient baseline cardiac characteristic. The arrhythmia detection system detects an arrhythmia episode using a physiologic signal sensed from the patient and the patient-specific arrhythmia detection threshold.

An implantable cardiac pacemaker, wherein the pacemaker is configured to apply pacing pulses to the heart of a person during operation of the pacemaker, and wherein the pacemaker comprises a motion detection system that comprises a first module and a second module. The first module is configured to continuously run during operation of the pacemaker. The second module is configured to receive a trigger signal to change from an idle state to an active state or to receive a further trigger signal to change from an active state to an idle state. An energy consumption per time unit of the second module in the active state is larger than in the idle state. When the second module is in its active state, the second module is configured to execute a rate adaptation algorithm that adapts a rate of the pacing pulses to meet a metabolic demand of the person.

Techniques are disclosed for detecting arrhythmia episodes for a patient. A medical device may receive one or more sensor values indicative of motion of a patient. The medical device may determine, based at least in part on the one or more sensor values, an activity level of the patient. The medical device may determine a heart rate threshold for triggering detection of an arrhythmia episode based at least in part on the activity level of the patient. The medical device may determine whether to trigger detection of the arrhythmia episode for the patient based at least in part on comparing a heart rate of the patient with the heart rate threshold. The medical device may, in response to triggering detection of the arrhythmia episode, collect information associated with the arrhythmia episode.

This document discusses, among other things, systems and methods to generate a first pacing waveform during a first pacing period and a second pacing waveform during a second pacing period, and alternate the first and second pacing periods to provide pacing-based hypertension therapy to a heart of a patient to reduce patient blood pressure, wherein the first pacing waveform has a first atrioventricular (AV) delay and the second pacing waveform has a second AV delay longer than the first AV delay. Physiologic information can be received from the patient, and one of the first or second pacing period for delivery to the patient can be determined using the received physiologic information.