Abstract: An apparatus for forming a lesion in tissue along a desired ablation path includes a guide member having a tissue-opposing surface for placement against a heart surface. A guide carriage is sized to be received within the guide member and moveable therein along a longitudinal axis. A flexible tubular member extends from a proximal end of said carriage and through a length of the guide member with the tubular member adapted to move the carriage within the guide member upon application of a force to the tubular member. A system urges the carriage to move in a path along an axis of the guide member by amount substantially identical to a displacement of a force application location on the flexible tubular member.

Abstract: An apparatus for forming a lesion in tissue along a desired ablation path includes a guide member having a tissue-opposing surface for placement against a heart surface. A guide carriage is sized to be received within the guide member and moveable along a longitudinal axis of the guide member. A tubular member extends from a proximal end of the carriage and out a proximal end of the guide member. An ablation element is carried in the carriage for movement. The ablation member is connected to a source of ablation energy through the tubular member. A sensor is provided for sensing a safety condition. The sensor is connected to a monitor external the guide member.

Abstract: A method and apparatus for applying energy to a target path on a tissue surface includes moving a proximal end of an energy source in a first direction by a first distance. During a first portion of the first distance, the source is in a non-energized mode. During a second portion of the first distance, the source in an energized mode. The proximal end is moved in a second direction along the path opposite the first direction and by a distance less than the first distance. During a first portion of the second direction, the source in a non-energized mode. During a second portion of the second direction, the source in an energized mode. The method compensates for a hysteresis between movement of a distal tip of the energy source and the proximal end.

Abstract: An apparatus for forming a lesion in tissue along a desired ablation path includes a guide member having a tissue-opposing surface for placement against a heart surface. A guide carriage is sized to be received within the guide member and moveable therein along a longitudinal axis. The carriage is configured to receive an optical fiber extending substantially axially within the carriage and bend the fiber for a discharge tip of the fiber to aim through a bottom wall of the guide member. The carriage is further configured to bend the fiber toward said discharge tip with a curved portion subject to mechanical stress and a straight portion at the fiber discharge tip. The straight portion is selected to have a length to dissipate thermal stress arising from reflectance of light from the tissue back into the discharge tip.

Abstract: A method and apparatus for treating a body tissue in situ (e.g., an atrial tissue of a heart to treat atrial fibrillation) include a lesion formation tool is positioned against the heart surface. The apparatus includes a guide member having a tissue-opposing surface for placement against a heart surface. The guide member also has interior surfaces and a longitudinal axis. A guide carriage is sized to be received with the guide member and moveable therein along the longitudinal axis. An optical fiber is positioned within the guide carriage with the carriage retaining the fiber. The carriage receives the fiber with an axis substantially parallel to the longitudinal axis and bends the fiber to a distal tip with an axis of said fiber at said distal tip at least 45 degrees to the longitudinal axis and aligned for discharge of laser energy through the tissue opposing surface.

Abstract: A method and apparatus for treating a body tissue in situ (e.g., an atrial tissue of a heart to treat) atrial fibrillation include a lesion formation tool is positioned against the heart surface. The lesion formation tool includes a guide member having a tissue-opposing surface for placement against a heart surface. An ablation member is coupled to the guide member to move in a longitudinal path relative to the guide member. The ablation member has an ablation element for directing ablation energy in an emitting direction away from the tissue-opposing surface. The guide member may be flexible to adjust a shape of the guide member for the longitudinal path to approximate the desired ablation path while maintaining the tissue-opposing surface against the heart surface. In one embodiment, the ablation member includes at least one radiation-emitting member disposed to travel in the longitudinal pathway.