Cardiofocus Corporation

Cambridge Heart, Inc.

Jeffrey M Arnold

Paul Albrecht

Lincoln S Baxter

Edward L Sinofsky

Richard J Cohen

Norman Erwin Farr

Gerald Melsky

Kevin S Librett

Paul Lander

Stephen W Sagon

Alfred Stancampiano

Paul E Grimshaw

Harvey Levin

Neil Judell

Paul G Grimshaw

Guided ablation instruments are disclosed for creating lesions in tissue, especially cardiac tissue for treatment of arrhythmias, including atrial fibrillation. In one aspect of the invention, a percutaneous catheter is disclosed with an endoscope positionable in the instrument's distal end region to obtain an image. The image allows the clinician to determine whether contact has been achieved (or blood has been cleared from an ablative energy transmission path) before ablation begins or while ablation is occurring. In one embodiment, percutaneous ablation catheters are disclosed having at least one central lumen and one or more balloon structures at the distal end region of the instrument. Also disposed in the distal end region are an illuminating light source and an endoscope capable of collecting sufficient light to relay an image to the user. The instruments can further include an ablation element. The ablation element can be a contact ablation element, or a radiant energy emitter, which is preferably independently positionable within the lumen of the instrument and adapted to project ablative energy through a transmissive region of the instrument body (and/or balloon) to a target tissue site proximate to the pulmonary veins. The energy can delivered without the need for contact between the energy emitter and the target tissue so long as a clear transmission pathway is established. The endoscope element of the instrument allows the clinician to determine the position of the instrument and, if radiant energy is to be employed, see if such a pathway is clear. Moreover, because the position of the radiant energy emitter can be varied, endoscopic guidance permits the clinician to select a desired location and dose for the lesion.

Guided cardiac ablation catheters

Methods and instruments are disclosed for creating lesions in tissue, especially cardiac tissue, for treatment of arrhythmias and the like, by employing an elastic balloon and an energy emitter, which is independently positionable within the lumen of the instrument and adapted to project a series of spots of ablative energy through a transmissive region of the balloon to a target tissue site. The energy emitter preferably is configured such the spots of energy result in a series of lesions formed in the target tissue region when the emitter is activated, the lesions having an average area ranging from about 5 mmto about 100 mm. In one aspect of the invention, percutaneous ablation instruments are disclosed in the form of catheter bodies having one or more balloon structures at the distal end region of the instrument and an energy emitting element, which is independently positionable and rotatable within a lumen of the instrument and adapted to project ablative energy through a transmissive region of the balloon to a target tissue site in contact with, or proximal to, the balloon surface.

Cardiac ablation catheters for forming overlapping lesions

A cardiac ablation instrument capable of removing blood from a treatment area is provided. The instrument includes a catheter configured to deliver a distal end thereof to a patient's heart. The instrument can also include an expandable element coupled to the distal end of the catheter wherein the expandable member is configured to be positioned adjacent a target area thereby defining a treatment area between the expandable member and the target area. Further, the instrument can include an irrigation mechanism configured to dispense an irrigation fluid from the catheter thereby displacing blood from the treatment area. Additionally, the instrument includes an energy emitter configured to deliver energy to tissue within the treatment area. The instrument can also include a contact sensor configured to determine the presence of such blood within the treatment area. Methods for ablating tissue are also provided.

Coaxial catheter instruments for ablation with radiant energy

Ablation methods and instruments are disclosed for creating lesions in tissue, especially cardiac tissue for treatment of arrhythmias and the like. Percutaneous ablation instruments in the form of coaxial catheter bodies are disclosed having at least one central lumen therein and having one or more balloon structures at the distal end region of the instrument. The instruments include an energy emitting element which is independently positionable within the lumen of the instrument and adapted to project radiant energy through a transmissive region of a projection balloon to a target tissue site to form a series of lesions on the target tissue.

Treatment of atrial fibrillation by overlapping curvilinear lesions

The present invention provides devices and methods for the treatment of atrial fibrillation. In one embodiment a deflectable sheath catheter includes an elongate catheter body having proximal and distal ends, the distal end having a distal tip region that includes a plurality of flexible segments with varying degrees of stiffness. A handle portion can be located at the proximal end of the catheter body to provide a steering mechanism that causes the distal tip region to deflect according to a compound curve.

Deflectable sheath catheters

A method of treating atrial fibrillation includes the step of positioning a distal portion of an ablation instrument in proximity to one or more pulmonary veins. The instrument has a hollow housing and an independently axially positionable energy emitter within the distal portion The energy emitter is configured and the distal portion is shaped such that a distance a beam of ablative energy travels from the energy emitter to the portion of the distal portion in contact with target tissue changes based on the energy emitter's location along the length of the instrument while the distal portion maintains its shape The energy emitter is a light emitting element and a beam-forming optical waveguide that receives light from the light emitting element. The waveguide projects onto the distal portion a hollow cone of radiation.

Methods for ablation with radiant energy

A cardiac ablation instrument includes a catheter body and a tear-shaped balloon that is connected to the catheter body. The instrument further includes a radiant energy emitter that is axially movable within a central lumen of the catheter body. A radiant energy transparent body surrounds the energy emitter and includes a plurality of illumination fibers disposed circumferentially about the energy emitter. A detector communicates with a contact sensing element and is configured to determine an amount of at least one color component of the reflected light The amount of the at least one color component being indicative of contact between the balloon and a target tissue site.

Heart function is improved by inducing heart rate variability through cardiac pacing. Electrical pacing signals are generated and applyied to a heart to improve heart function. The pacing signals are controlled to vary a heart rate during periods of less than five minutes in duration to induce beneficial heart rate variability.

Cardiac pacing to induce heart rate variability

Cardiac electrical stability is assessed by generating a measure of cardiac electrical stability (e.g., an alternans measure) using a physiologic signal representative of activity of a patient's heart, generating a reference signal that provides information regarding whether the measure is representative of cardiac electrical stability, and visually presenting the measure and the reference signal in a way that permits visual evaluation of whether the measure is representative of cardiac electrical stability in view of characteristics of the reference signal.

Assessing cardiac electrical stability

A method of reducing noise in a biological signal, such as an ECG signal, includes acquiring a biological signal, comparing the biological signal to a representative signal, and generating a predicted signal corresponding to the representative signal when the biological signal sufficiently matches the representative signal. The predicted signal is subtracted from the biological signal to produce a second signal, and a filter is applied to the second signal to produce a filtered signal. The predicted signal and the filtered signal then are combined to produce a noise-reduced signal.

Reducing noise in a biological signal

A localized cardiac measure, such as a localized measure of myocardial ischemia, is obtained by applying sensors to a subject, where the sensors are configured to produce electrical signals representative of cardiac activity of the subject. The subject's heart is then physiologically stressed by, for example, exercise stress testing, and electrical signals are received from at least two of the sensors. The received signals then are processed to obtain a localized cardiac measure.

Growing community of inventors

Wellesley, MA, United States of America

Jeffrey M Arnold