Patent ID: 8241272
Filing Date: 2012-08-14
Classification: A61B,A61L,A61N

Abstract:
1. A method of treating atrial fibrillation, comprising: positioning a distal portion of an ablation instrument in proximity to one or more pulmonary veins, the ablation instrument having a hollow housing and an independently axially positionable energy emitter within the distal portion, the distal portion being transmissive to radiant energy, wherein 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 ablation instrument while the distal portion maintains its shape, wherein the energy emitter comprises a light emitting element and a beam-forming optical waveguide that receives light from the light emitting element, wherein the wavequide is located at a distal end of the light emitting element and is configured so as to project onto the distal portion a hollow cone of radiation; axially positioning the energy emitter at any of a plurality of locations along a length of distal portion; activating the energy emitter to transmit energy to the waveguide located at the distal end of the light emitting element; wherein the waveguide causes the transmitted energy to be confined to an annular band of light energy that is focused on the target tissue region; and conveying the annular band of light energy through the distal portion of the housing to form an annular lesion in proximity to the one or more pulmonary veins.