1. Field of Invention
The present invention relates generally to catheter systems used in diagnosis and treatment of various body tissues and, more specifically, to steering systems incorporated into catheter systems for ablating cardiac tissue in the treatment of electrophysiological diseases.
2. Description of the Related Art
As is well know, catheters provide medical professionals access to various interior regions of the human body, in a minimally invasive manner, in support of diagnosis and treatment. Catheters allow such professionals to place one or more medical instruments, pharmacological agents or other matter at a target tissue site. For example, in cardiac procedures in support of diagnosis and treatment of atrial fibrillation, catheters provide access to various chambers of the heart, carrying ablation devices which translate therein to such sites for ablation of specific cardiac tissue associated with atrial fibrillation.
Ablation of tissue, cardiac tissue for example, is directly related to the orientation of the ablation element from which energy sufficient to ablate biological tissue is emitted. For such procedures, precise control of the ablation device is desirable to ensure proper placement of the ablation element utilized in creation of one or more desired lesions. As a surgeon, or other medical professional, manipulates the proximal end of the catheter system, the distal end of the catheter must be responsive to such movement in a very predetermined, smooth-flowing and proportional way.
Proper placement of an ablation device is exasperated by the fact that some ablative energy technologies require energy transmission conduits which are bulky, or otherwise constructed from materials less flexible, making the distal portion of the catheter difficult to properly position. For example, distal portions of optical fiber or microwave based ablation systems, or catheter systems comprising an endoscopic device, may be more difficult to maneuver due to the lack of {flexibility in the transmission mediums utilized therein. As should be readily apparent, when the distal portion of an ablation catheter system is not properly positioned, ablative energy is not properly directed and applied to the target tissue, resulting in poor lesion formation. It is therefore essential that the ablative device be able to be manipulated and sufficiently controlled to be properly positioned to transfer the requisite energy to ablate biological tissue and create a desired lesion therein.