Indifferent electrode pad systems and methods for tissue ablation

Abstract

Systems and methods for transmitting energy through patient tissue involve the use of an indifferent pad assembly in conjunction with an ablation probe. Systems may include an electrical surgical unit having a power output connector, a first power return connector, and a second power return connector. Systems may also include an ablation probe coupleable with the power output connector of the electrical surgical unit, and an indifferent pad assembly having a conductive mechanism coupled with an electrical and thermal insulator mechanism, and a wire assembly coupled with the conductive mechanism. The wire assembly can include a first connector coupleable with the first power return connector of the electrical surgical unit, and a second connector coupleable with the second power return connector of the electrical surgical unit.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS[0001]This application is a nonprovisional of, and claims the benefit of priority to, U.S. Provisional Patent Application No. 61 / 318,474 filed Mar. 29, 2010 (docket no. 87512-784699; previously 021063-003500US). This application is also related to U.S. patent application Ser. No. ______ filed Mar. 29, 2011 (docket no. 87512-798150; previously 021063-004100US) and U.S. Pat. No. 7,288,090, the content of which is incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]Embodiments of the present invention related to medical devices and methods, and in particular to cardiac ablation systems and methods.[0003]Atrial fibrillation (AF) is a common clinical condition, and presents a substantial medical issue to aging populations. AF is costly to health systems, and can cause complications such as thrombo-embolism, heart failure, electrical and structural remodeling of the heart, and even death.[0004]For many years, the main treatment for atr...

AI Technical Summary

Benefits of technology

[0008]Embodiments of the present invention encompass ablation systems and methods involving the use of a flexible indifferent electrode pad assembly. In some cases, the indifferent electrode pad assembly is shaped to fit in the pericardial space and conform to the posterior portion of the left atrium and right atrium. The pad assembly can include a conductive surface on the side of the pad that faces the atria, in combination with an electrical and thermal insulator. Relatedly, the pad can provide a return path in the pericardial space. The conductive surface can be electrically coupled with a thin flexible cable that connects to an Electrical Surgical Unit (ESU) to return current originating from a separate ablation device or probe. The pad assembly can operate to prevent or inhibit potential damage to the esophagus and to other non-cardiac tissues or devices, for example by isolating those tissues or preventing transmitted ablation energy from reaching them. The pad assembly, used in combination with an endocardial surgical ablation monopolar probe, can also enhance the effect of the ablation because current spread can be less than would otherwise occur when a monopolar probe is used in conjunction with a return electrode placed on the patient's skin. For lesions applied near the posterior aspect of the atria, system embodiments can produce lesions similar to those made by bipolar clamping devices, while maintaining the benefit of easy application of all ablation lines used for a modified MAZE procedure. Hence, embodiments of the present invention provide an efficient and safe ablation treatment, without the geometric constraints or limitations associated with some bipolar treatments, and without the risk of complication sometimes associated with other monopolar treatments.

[0009]In an exemplary approach, an indifferent pad assembly may be used in conjunction with a monopolar probe or wand device such as the COBRA® Surgical Probe (Estech, San Ramon, Calif.), a malleable epicardial or endocardial probe that utilizes multiple electrodes to create uniform, reproducible linear lesions. This combination enables the flexibility and ease of use of monopolar ablation and the efficacy of the bipolar clamping devices. Relatedly, combination indifferent pad assembly and monopolar probe systems can be used to safely treat patient tissue with reduced risk to surrounding tissue. For example, the pad assembly and probe can be used to treat atrial tissue, without a high risk of damage to non-cardiac tissue such as the esophagus, lung, and the like.

Problems solved by technology

Atrial fibrillation (AF) is a common clinical condition, and presents a substantial medical issue to aging populations.

AF is costly to health systems, and can cause complications such as thrombo-embolism, heart failure, electrical and structural remodeling of the heart, and even death.

This procedure was found to be highly efficacious but was associated with a high morbidly rate.

However, some monopolar approaches may present a risk of injury or damage to tissue located near the treatment site.

Relatedly, some current bipolar approaches may be limited due to structural constraints associated with the use of a clamping device.

For example, although bipolar radiofrequency can be a reliable way to create transmural atrial scars, the clamping design of bipolar devices can limit its use in certain anatomical applications.

Images