Abstract: A device for monitoring temperature generated by an ablation apparatus on organic tissue is provided. The device comprises a temperature sensing pad; and an output device to receive and display a representation of a lesion found on the ablated organic tissue. Ablation systems incorporating the device and methods of using the device are also provided.

Abstract: A system for creating lesions and assessing their completeness or transmurality. Assessment of transmurality of a lesion is accomplished by monitoring the impedance of the tissue to be ablated. Rather than attempting to detect a desired drop or a desired increase impedance, completeness of a lesion is detected in response to the measured impedance remaining at a stable level for a desired period of time, referred to as an impedance plateau. The mechanism for determining transmurality of lesions adjacent individual electrodes or pairs may be used to deactivate individual electrodes or electrode pairs, when the lesions in tissue adjacent these individual electrodes or electrode pairs are complete, to create an essentially uniform lesion along the line of electrodes or electrode pairs, regardless of differences in tissue thickness adjacent the individual electrodes or electrode pairs.

Abstract: A system and method for creating lesions and assessing their completeness or transmurality. Assessment of transmurality of a lesion is accomplished by monitoring the depolarization signal in a local electrogram taken using electrodes located adjacent the tissue to be ablated. Following onset of application of ablation energy to heart tissue, the local electrogram is measured with electrodes located adjacent tissue to be ablated so that the ablation energy to ablation elements can be selectively reduced or terminated when transmurality is detected.

Abstract: An ablation system and a method of its use. The system includes a first elongated ablation component carrying a longitudinally extending mechanism for delivery of ablation energy along its length, and a second elongated ablation component movable relative to the first ablation component. The first and second components are provided with a mechanism mounted to and extending along the first and second components for magnetically attracting the first and second components toward one another along the length of the first mechanism for delivery of ablation energy. Preferably, the second elongated ablation component also carries a longitudinally extending mechanism for delivery of ablation energy along its length.

Abstract: Methods for delivering precise amounts of fluid into cardiac tissue for the purpose of facilitating ablation of the tissue along a desired lesion line. One method injects fluid through a hollow needle. The injected fluid can be a highly conductive fluid injected in conjunction with radiofrequency ablation to create an ablative virtual electrode. The injected conductive fluid can provide deeper and narrower conduction paths and resulting lesions. Radiofrequency ablation can be performed at the same time as the fluid injection, using the injection device as an electrode, or subsequent to the fluid injection, using a separate device. In some methods, the injected fluid is a protective fluid, injected to protect tissue adjacent to the desired lesion line. Fluid delivery can be endocardial, epicardial, and epicardial on a beating heart. The present methods find one use in performing maze procedures to treat atrial fibrillation.

Abstract: A system and method for creating lesions and assessing their completeness or transmurality. Assessment of transmurality of a lesion is accomplished by monitoring the depolarization signal amplitude in a local electrogram taken using electrodes located adjacent the tissue to be ablated. Following onset of application of ablation energy to heart tissue, the amplitude of a local electrogram measured with electrodes located adjacent tissue to be ablated first gradually drops and then stabilizes, indicating that the tissue being monitored has ceased making any contribution to the sensed electrogram. The amplitude drop and/or the following amplitude plateau may be used alone or together as indicators of transmurality. Detection of a rapid drop in amplitude may be employed as an indicator that the ablation process is proceeding too quickly and may be employed to trigger a reduction in the power of applied ablation energy.

Abstract: A method and system for ablating tissue to provide a desired set of lesions. The system includes an ablation apparatus having an elongated shapeable section carrying a mechanism such as an electrode for applying ablation energy along the shapeable section. The shapeable section includes a member of shape memory material having a memorized configuration. The shapeable section is shaped manually or using fixtures to display a configuration corresponding to one of the desired lesions and is then employed to create the desired lesion. Thereafter the shapeable section is heated to cause it to resume its memorized configuration. Shaping, heating and ablating to create lesions are continued as necessary provide the desired set of lesions. In some embodiments of the invention, heating may be accomplished using heating elements built into the shapeable section.

Abstract: A system and method for creating lesions and assessing their completeness or transmurality. Assessment of transmurality of a lesion is accomplished by monitoring the impedance of the tissue to be ablated. Rather than attempting to detect a desired drop or a desired increase impedance, completeness of a lesion is detected in response to the measured impedance remaining at a stable level for a desired period of time, referred to as an impedance plateau. The mechanism for determining transmurality of lesions adjacent individual electrodes or pairs may be used to deactivate individual electrodes or electrode pairs, when the lesions in tissue adjacent these individual electrodes or electrode pairs are complete, to create an essentially uniform lesion along the line of electrodes or electrode pairs, regardless of differences in tissue thickness adjacent the individual electrodes or electrode pairs.

Abstract: A catheter assembly and method for treatment of cardiac arrhythmia, for example, atrial fibrillation, by electrically isolating a vessel, such as a pulmonary vein, from a chamber, such as the left atrium. The catheter assembly includes a catheter body and at least one electrode. The catheter body includes a proximal portion, an intermediate portion and a distal portion. The intermediate portion extends from the proximal portion and defines a longitudinal axis. The distal portion extends from the intermediate portion and forms a substantially closed loop transverse to the longitudinal axis. The at least one electrode is disposed along the loop. With this configuration, the loop is axially directed into contact with the chamber wall about the vessel ostium. Upon energization, the electrode ablates a continuous lesion pattern about the vessel ostium, thereby electrically isolating the vessel from the chamber.

Abstract: A device for monitoring temperature generated by an ablation apparatus on organic tissue is provided. The device comprises a temperature sensing pad; and an output device to receive and display a representation of a lesion found on the ablated organic tissue. Ablation systems incorporating the device and methods of using the device are also provided.

Abstract: A catheter assembly and method for treatment of cardiac arrhythmia, for example, atrial fibrillation, by electrically isolating a vessel, such as a pulmonary vein, from a chamber, such as the left atrium. The catheter assembly includes a catheter body and at least one electrode. The catheter body includes a proximal portion, an intermediate portion and a distal portion. The intermediate portion extends from the proximal portion and defines a longitudinal axis. The distal portion extends from the intermediate portion and forms a substantially closed loop transverse to the longitudinal axis. The at least one electrode is disposed along the loop. With this configuration, the loop is axially directed into contact with the chamber wall about the vessel ostium. Upon energization, the electrode ablates a continuous lesion pattern about the vessel ostium, thereby electrically isolating the vessel from the chamber.

Abstract: A catheter assembly and method for treatment of cardiac arrhythmia, for example, atrial fibrillation, by electrically isolating a vessel, such as a pulmonary vein, from a chamber, such as the left atrium. The catheter assembly includes a catheter body and at least one electrode. The catheter body includes a proximal portion, an intermediate portion and a distal portion. The intermediate portion extends from the proximal portion and defines a longitudinal axis. The distal portion extends from the intermediate portion and forms a substantially closed loop transverse to the longitudinal axis. The at least one electrode is disposed along the loop. With this configuration, the loop is axially directed into contact with the chamber wall about the vessel ostium. Upon energization, the electrode ablates a continuous lesion pattern about the vessel ostium, thereby electrically isolating the vessel from the chamber.

Abstract: A system and method for creating lesions and assessing their completeness or transmurality. Assessment of transmurality of a lesion is accomplished by monitoring the impedance of the tissue to be ablated. Rather than attempting to detect a desired drop or a desired increase impedance, completeness of a lesion is detected in response to the measured impedance remaining at a stable level for a desired period of time, referred to as an impedance plateau. The mechanism for determining transmurality of lesions adjacent individual electrodes or pairs may be used to deactivate individual electrodes or electrode pairs, when the lesions in tissue adjacent these individual electrodes or electrode pairs are complete, to create an essentially uniform lesion along the line of electrodes or electrode pairs, regardless of differences in tissue thickness adjacent the individual electrodes or electrode pairs.

Abstract: A suction assisted ablation device having a support surface, suction elements disposed adjacent the support surface, at least one electrode and at least one suction conduit is provided. The device may further include fluid openings, which allow fluid to irrigate target tissue and aid in ablation. A method for ablating tissue using suction is also provided.

Abstract: A trans-septal guide catheter for providing access through the septum separating a first heart chamber from a second heart chamber that includes an elongated guide catheter body extending between guide catheter proximal and distal ends. A distal segment of the guide catheter is adapted to be inserted through the septum to locate the distal segment of the guide catheter within one of the first heart chamber and the second heart chamber. The catheter body encloses a guide catheter lumen adapted to provide access into the one of the first heart chamber and the second heart chamber through a guide catheter lumen proximal end opening and a guide catheter lumen distal end opening.

Abstract: A device for monitoring temperature generated by an ablation apparatus on organic tissue is provided. The device comprises a temperature sensing pad; and an output device to receive and display a representation of a lesion found on the ablated organic tissue. Ablation systems incorporating the device and methods of using the device are also provided.

Abstract: A method and system for ablating tissue to provide a desired set of lesions. The system includes an ablation apparatus having an elongated shapeable section carrying a mechanism such as an electrode for applying ablation energy along the shapeable section. The shapeable section includes a member of shape memory material having a memorized configuration. The shapeable section is shaped manually or using fixtures to display a configuration corresponding to one of the desired lesions and is then employed to create the desired lesion. Thereafter the shapeable section is heated to cause it to resume its memorized configuration. Shaping, heating and ablating to create lesions are continued as necessary provide the desired set of lesions. In some embodiments of the invention, heating may be accomplished using heating elements built into the shapeable section.

Abstract: A catheter assembly and method for treatment of cardiac arrhythmia, for example, atrial fibrillation, by electrically isolating a vessel, such as a pulmonary vein, from a chamber, such as the left atrium. The catheter assembly includes a catheter body and at least one electrode. The catheter body includes a proximal portion, an intermediate portion and a distal portion. The intermediate portion extends from the proximal portion and defines a longitudinal axis. The distal portion extends from the intermediate portion and forms a substantially closed loop transverse to the longitudinal axis. The at least one electrode is disposed along the loop. With this configuration, the loop is axially directed into contact with the chamber wall about the vessel ostium. Upon energization, the electrode ablates a continuous lesion pattern about the vessel ostium, thereby electrically isolating the vessel from the chamber.

Abstract: A suction assisted ablation device having a support surface, suction elements disposed adjacent the support surface, at least one electrode and at least one suction conduit is provided. The device may further include fluid openings, which allow fluid to irrigate target tissue and aid in ablation. A method for ablating tissue using suction is also provided.

Abstract: An ablation system and a method of its use. The system includes a first elongated ablation component carrying a longitudinally extending mechanism for delivery of ablation energy along its length, and a second elongated ablation component movable relative to the first ablation component. The first and second components are provided with a mechanism mounted to and extending along the first and second components for magnetically attracting the first and second components toward one another along the length of the first mechanism for delivery of ablation energy. Preferably, the second elongated ablation component also carries a longitudinally extending mechanism for delivery of ablation energy along its length.