Ablation systems and methods of the present disclosure are directed toward delivering pulsed radiofrequency (RF) energy to target tissue. The pulsations of the RF energy, combined with cooling at a surface of the target tissue, can advantageously promote local heat transfer in the target tissue to form lesions having dimensions larger than those that can be safely formed in tissue using non-pulsed RF energy under similar conditions.

Ablation systems of the present disclosure facilitate the safe formation of wide and deep lesions. For example, ablation systems of the present disclosure can allow for the flow of irrigation fluid and blood through an expandable ablation electrode, resulting in efficient and effective cooling of the ablation electrode as the ablation electrode delivers energy at a treatment site of the patient. Additionally, or alternatively, ablation systems of the present disclosure can include a deformable ablation electrode and a plurality of sensors that, in cooperation, sense the deformation of the ablation electrode, to provide a robust indication of the extent and direction of contact between the ablation electrode and tissue at a treatment site.

A method for assessing a lesion formed between first and second regions of body cavity tissue, the method including using a first probe in contact with the tissue at a stimulus location in the first region, and applying to the tissue or sensing in the tissue a first activation signal having a first activation peak at a first time. Respective second activation signals having respective second activation peaks following the first activation signal are received from a second probe having multiple electrodes in contact with the tissue at respective sensing locations in the second region, and based on a temporal relation between the first and second activation peaks and a spatial relation between the stimulus location and the sensing locations, one of the multiple electrodes proximal to a gap in the lesion is identified. A map of the body cavity is displayed with the identified electrode marked on the map.

Ablation systems of the present disclosure facilitate the safe formation of wide and deep lesions. For example, ablation systems of the present disclosure can allow for the flow of irrigation fluid and blood through an expandable ablation electrode, resulting in efficient and effective cooling of the ablation electrode as the ablation electrode delivers energy at a treatment site of the patient. Additionally, or alternatively, ablation systems of the present disclosure can include a deformable ablation electrode and a plurality of sensors that, in cooperation, sense the deformation of the ablation electrode, to provide a robust indication of the extent and direction of contact between the ablation electrode and tissue at a treatment site.

A method for assessing a lesion formed between first and second regions of body cavity tissue, the method including using a first probe in contact with the tissue at a stimulus location in the first region, and applying to the tissue or sensing in the tissue a first activation signal having a first activation peak at a first time. Respective second activation signals having respective second activation peaks following the first activation signal are received from a second probe having multiple electrodes in contact with the tissue at respective sensing locations in the second region, and based on a temporal relation between the first and second activation peaks and a spatial relation between the stimulus location and the sensing locations, one of the multiple electrodes proximal to a gap in the lesion is identified. A map of the body cavity is displayed with the identified electrode marked on the map.

This document describes methods and devices for treating ventricular fibrillation. For example, this document describes methods of performing electroporation of a ventricle and electroporation catheters. The methods can include inserting a distal end portion of a catheter into a ventricle of a heart of a patient, inflating a balloon coupled to the distal end portion of the catheter, occluding a valve of the heart associated with the ventricle with the balloon, injecting a fluid into the ventricle via an aperture defined by the distal end portion of the catheter, and generating an electrical current via an electrode on the distal end portion of the catheter.

Various aspects of the present disclosure are directed toward apparatuses, systems, and methods for applying ablation therapy to a tissue region. The apparatuses, systems, and methods may include a balloon structure and one or more electrodes arranged on or within the balloon structure and configured to deliver energy to the tissue region.

An ablation catheter having an expandable tip is disclosed herein. In some implementations, the ablation catheter includes a catheter shaft, an irrigation lumen, and an expandable tip secured to the catheter shaft. In some implementations, the expandable tip includes a balloon defining a volume in communication with the irrigation lumen. In these and other implementations, the balloon defines a plurality of irrigation orifices in fluid communication with the volume. In these and other implementations, the expandable tip comprises an ablation electrode and a plurality of sensing electrodes disposed along a distal section of the balloon. In these and still other implementations, the sensing electrodes disposed along the distal section of the balloon can be electrically isolated from and bounded by the ablation electrode.

A method of occlusion detection is disclosed. The method comprises the steps of positioning a medical tool coupled to a distal portion of a distal end of a delivery catheter at a target cavity within a patient. The medical tool includes an expandable balloon, and at least one sensor. The expandable balloon is expanded when positioned at the target cavity. The expandable balloon includes a membrane formed of a plurality of irrigation pores. Fluid is introduced into the target cavity either by injection or through the pores, or both. Using a sensor, a characteristic of blood is detected with the target cavity. The characteristic of blood is processed to determine the presence or absence of an occlusion within the cavity.

Sinusitis and other disorders of the ear, nose and throat are diagnosed and/or treated using minimally invasive approaches with flexible or rigid instruments. Various methods and devices are used for remodeling or changing the shape, size or configuration of a sinus ostium or duct or other anatomical structure in the ear, nose or throat; implanting a device, cells or tissues; removing matter from the ear, nose or throat; delivering diagnostic or therapeutic substances or performing other diagnostic or therapeutic procedures. Introducing devices (e.g., guide catheters, tubes, guidewires, elongate probes, other elongate members) may be used to facilitate insertion of working devices (e.g. catheters e.g. balloon catheters, guidewires, tissue cutting or remodeling devices, devices for implanting elements like stents, electrosurgical devices, energy emitting devices, devices for delivering diagnostic or therapeutic agents, substance delivery implants, scopes etc.) into the paranasal sinuses or other structures in the ear, nose or throat.