The present invention relates to a myocardial spectrometer probe, comprising: at least two separate light guides (120A, 120B), insertable in a tissue, wherein a first light guide (120A, 120B) is arranged to deliver light and a second light guide (120A, 120B) is arranged to collect light, and wherein the first light guide (120A, 120B) and the second light guide (120A, 120B) are arranged distinct to each other.

Disclosed are various examples and embodiments of systems, devices, components and methods configured to extract atrial signals from electrical signals acquired from a patient suffering from atrial fibrillation. The electrical signals acquired from the patient may be intra-cardiac signals or body surface electrode signals, or both. At least portions of QRS or QRS-T complexes corresponding to determined initial synchronization times are used to generate Fast Fourier Transforms (FFTs) corresponding to the extracted QRS complexes. A series of steps follow to generate isolated atrial signals corresponding to each electrical signal by subtracting generated reconstructed signals corresponding to each such electrical signal therefrom.

A conformational state of a medical device operated within a body lumen is determined by measuring, using the medical device as an electrode, an electrical parameter which varies in a correspondence with a conformational state (e.g., deployment state) of the portion of the medical device used as the electrode. The conformational state of the medical device is determined, based on the electrical parameter; and an image is presented indicating the determined conformational state. In some embodiments, the electrical parameter is a self-impedance of the portion of the medical device used as the electrode. In some embodiments, current positioning of the medical device is used as part of calibrating a parametric relationship between the electrical parameter and conformational states of the medical device.

Pigtail catheters and relates methods for measuring a pressure gradient across a bodily narrowing are disclosed. A pigtail catheter can comprise a proximal shaft segment and a distal shaft segment. The proximal shaft segment can include double lumen tubing defining a proximal pressure lumen and a non-coaxial, distal pressure lumen. In an example, the distal pressure lumen has a generally circular cross-sectional shape, and the proximal pressure lumen has a generally crescent or kidney cross-sectional shape that wraps partially around the distal pressure lumen. The distal shaft segment can include at least one distal orifice positionable distal to the bodily narrowing and at least one proximal orifice positionable proximal to the bodily narrowing. Each orifice can have a diameter of at least about 0.018 inches, for example. A manifold can be coupled to a proximal end of the proximal shaft segment and can include a proximal pressure port in communication with the proximal pressure lumen and a distal pressure port in communication with the distal pressure lumen.

A myocardial infarction detection method and apparatus is described that includes a stiffness measurement step of measuring myocardial stiffness of a cardiac muscle of a subject, and a determination step of determining, based on the myocardial stiffness, whether or not infarction is present in the cardiac muscle.

Methods, systems, and coaptation measurement devices as described herein include an elongate sensor body at the end of a proximal connecting member, and a plurality of sensors in an array across a face of the sensor body, wherein each sensor of the plurality of sensors is configured to detect if a portion of a heart valve is in contact with the sensor.

Transducer-based systems and methods may be configured to display a graphical representation of a transducer-based device, the graphical representation including graphical elements corresponding to transducers of the transducer-based device, and also including between graphical elements respectively associated with a set of the transducers and respectively associated with a region of space between the transducers of the transducer-based device. Selection of graphical elements and/or between graphical elements can cause activation of the set of transducers associated with the selected elements. Transducer activation characteristics, such as initiation time, activation duration, activation sequence, and energy delivery characteristics, can vary based on numerous factors. Visual characteristics of graphical elements and between graphical elements can change based on an activation-status of the corresponding transducers. Activation requests for a set of transducers can be denied if it is determined that a transducer in the set of transducers is unacceptable for activation.

A heart size measuring tool includes a tubular body, a flexible measuring cord having length indicia, a measuring cord support mechanism movable between retracted and extended states with respect to the body, and an actuating mechanism to move the measuring cord support mechanism. When in the retracted state the measuring cord support mechanism is positioned within the tubular body with the measuring cord in a collapsed position. When the measuring cord support mechanism is in the extended state the measuring cord extends around a portion of a heart to be measured. A scale on the body can be used in connection with the indicia on the measurement cord to provide a reading of the heart size.

Some aspects relate to systems, devices, and methods of delivering rate responsive pacing therapy. The method includes monitoring activity information related to an activity level of a patient and delivering rate responsive pacing (RRP) to the patient at a pacing rate corresponding to a RRP profile. The RRP profile may be used to generate the pacing rate based on the activity information and may be adjusted based on the monitored activity information.

Delivery system for fixation device, including guide catheter with proximal end portion having proximal end port, distal end portion having distal end port, and inner surface defining inner lumen extending in fluid communication between proximal end port and distal end port. Delivery catheter extending through the inner lumen to define annular space between outer surface of the delivery catheter and inner surface of the guide catheter. A pressure sensor proximate the proximal end portion in fluid communication with the annual space to monitor fluid pressure. The distal end portion of the guide catheter includes flow passages in fluid communication between an exterior of the distal end portion and the annular space.