Abstract: An ablation system which transmits radio frequency (RF) energy for the ablation of biological tissues has a transmission line and an RF antenna disposed at the distal portion of the transmission line. An RF signal generator supplies RF energy to the proximal end of the cable for transmission to the antenna, and an electrically tunable transformer is connected between the signal generator and the antenna. The transformer is tuned based on detection of the reflected power level from the antenna so as to reduce or minimize reflected power, thereby increasing RF energy coupling between the antenna and tissue.

Abstract: An RF ablation system has a hollow conductive coaxial cable comprising inner and outer coaxial tubular conductors, and an ablating member mounted at the distal end portion of the cable for delivery of radio frequency energy including microwaves to the target body tissue. The inner conductor has a central lumen and extends at least up to the ablating member. At least one electromagnetic tracking sensor coil with a magnetic core is located in the central lumen at the distal end portion of the cable, close to the distal tip of the cable, and connected to a signal processing unit. An electromagnetic field generator positioned in the vicinity of a patient undergoing treatment generates an electromagnetic field which induces a voltage in the sensor coil. The signal processing unit uses the induced voltage to calculate the position and orientation of the distal end portion or tip of the catheter in a patient's body.

Abstract: An ablation device which transmits radio frequency (RF) energy for the ablation of biological tissues has elongate inner and outer coaxial conductors extending from a proximal portion to a distal portion. An RF antenna is disposed at the distal portion of the device and transmits RF energy for ablation of a tissue region to be treated. Reflection of energy from the tissue or the ablation point is reduced by providing multiple layers of dielectric media about the antenna, or by providing a gradual transition point from the conductors to the antenna tip, by means of a longitudinally stepped dielectric layer transformer.

Abstract: A coaxial cable apparatus which transmits radio frequency (RF) energy for the ablation of biological tissues has inner and outer coaxial conductors extending substantially the entire length of the cable from a proximal end portion to a distal end portion. An RF antenna is disposed at the distal end portion of the cable and transmits RF energy for ablation of a tissue region to be treated. An angioplasty balloon is disposed over the RF antenna and communicates with a fluid supply and extraction passageway extending through the cable to allow the balloon to be inflated for an angioplasty procedure including tissue ablation, and to be deflated after the procedure is complete.

Abstract: A hollow coaxial cable adapted for conduction of radio frequency (RF) energy, particularly microwave energy, has a proximal end and a distal end and comprises coaxial inner and outer conductors extending substantially the entire length of the cable from the proximal end to a distal end portion of the cable with a dielectric medium disposed between the inner and outer conductors. The inner conductor comprises an elongated electrically conductive tubular member having a hollow, axially extending lumen, and the outer conductor comprises an elongated electrically conductive tubular member disposed in a substantially coaxial relationship over at least a portion of the inner conductor. An ablating member which delivers radio frequency energy, particularly microwave energy, to body tissue is disposed at a distal end portion of the cable.

Abstract: A RF catheter system includes a catheter with a proximal portion, a distal portion having a distal end and a lumen extending from the proximal portion to the distal portion. Inner and outer coaxially aligned conductors extend within the catheter and are coaxial with the lumen. A deflectable catheter guide is disposed within the catheter lumen and extends proximally within the catheter lumen and terminates distally of the distal end of the catheter to define a biological ablation pathway. A radio-frequency antenna is disposed at the distal portion of the catheter and is in electrical communication with the inner and outer coaxially aligned conductors. The radio-frequency antenna is adaptable to receive and transmit radio-frequency energy for ablating biological tissue along the ablation pathway.

Abstract: A coaxial cable apparatus which transmits radio frequency (RF) energy for the ablation of biological tissues has inner and outer coaxial conductors extending from a proximal portion to a distal portion. An RF antenna is disposed at the distal portion of the cable and transmits RF energy for ablation of a tissue region to be treated. At least one ultrasonic transducer is also disposed at the distal portion of the cable to direct ultrasonic frequency energy to a tissue region. The ultrasonic transducer detects reflected ultrasonic signals from the tissue region and provides a signal output which varies dependent on the density of tissue over the monitored tissue region. The reflected ultrasonic signal can be monitored before, during, and after ablation treatment.

Abstract: An RF ablation system has a hollow conductive coaxial cable comprising inner and outer coaxial tubular conductors, and an ablating member mounted at the distal end portion of the cable for delivery of radio frequency energy including microwaves to the target body tissue. The inner conductor has a central lumen and extends at least up to the ablating member. At least one electromagnetic tracking sensor coil with a magnetic core is located in the central lumen at the distal end portion of the cable, close to the distal tip of the cable, and connected to a signal processing unit. An electromagnetic field generator positioned in the vicinity of a patient undergoing treatment generates an electromagnetic field which induces a voltage in the sensor coil. The signal processing unit uses the induced voltage to calculate the position and orientation of the distal end portion or tip of the catheter in a patient's body.

Abstract: A RF catheter system includes a catheter with a proximal portion, a distal portion having a distal end and a lumen extending from the proximal portion to the distal portion. Inner and outer coaxially aligned conductors extend within the catheter and are coaxial with the lumen. A deflectable catheter guide is disposed within the catheter lumen and extends proximally within the catheter lumen and terminates distally of the distal end of the catheter to define a biological ablation pathway. A radio-frequency antenna is disposed at the distal portion of the catheter and is in electrical communication with the inner and outer coaxially aligned conductors. The radio-frequency antenna is adaptable to receive and transmit radio-frequency energy for ablating biological tissue along the ablation pathway.

Abstract: An ablation device which transmits radio frequency (RF) energy for the ablation of biological tissues has elongate inner and outer coaxial conductors extending from a proximal portion to a distal portion. An RF antenna is disposed at the distal portion of the device and transmits RF energy for ablation of a tissue region to be treated. Reflection of energy from the tissue or the ablation point is reduced by providing multiple layers of dielectric media about the antenna, or by providing a gradual transition point from the conductors to the antenna tip, by means of a longitudinally stepped dielectric layer transformer.

Abstract: An ablation system which transmits radio frequency (RF) energy for the ablation of biological tissues has a transmission line and an RF antenna disposed at the distal portion of the transmission line. An RF signal generator supplies RF energy to the proximal end of the cable for transmission to the antenna, and an electrically tunable transformer is connected between the signal generator and the antenna. The transformer is tuned based on detection of the reflected power level from the antenna so as to reduce or minimize reflected power, thereby increasing RF energy coupling between the antenna and tissue.

Abstract: A coaxial cable apparatus which transmits radio frequency (RF) energy for the ablation of biological tissues has inner and outer coaxial conductors extending substantially the entire length of the cable from a proximal end portion to a distal end portion. An RF antenna is disposed at the distal end portion of the cable and transmits RF energy for ablation of a tissue region to be treated. An angioplasty balloon is disposed over the RF antenna and communicates with a fluid supply and extraction passageway extending through the cable to allow the balloon to be inflated for an angioplasty procedure including tissue ablation, and to be deflated after the procedure is complete.

Abstract: A coaxial cable apparatus which transmits radio frequency (RF) energy for the ablation of biological tissues has inner and outer coaxial conductors extending from a proximal portion to a distal portion. An RF antenna is disposed at the distal portion of the cable and transmits RF energy for ablation of a tissue region to be treated. At least one ultrasonic transducer is also disposed at the distal portion of the cable to direct ultrasonic frequency energy to a tissue region. The ultrasonic transducer detects reflected ultrasonic signals from the tissue region and provides a signal output which varies dependent on the density of tissue over the monitored tissue region. The reflected ultrasonic signal can be monitored before, during, and after ablation treatment.

Abstract: A radio-frequency based catheter system and method for ablating biological tissues within the body vessel of a patient comprises a radio-frequency (“RF”) generator for selectively generating a high frequency RF energy signal in a deployable catheter having an RF transmission line, an RF antenna mounted on the distal portion of the catheter, and a temperature sensor also mounted on a distal portion of the catheter for detecting temperature adjacent an ablation site. A control system adjusts the RF energy signal so that the detected temperature is at or close to a selected temperature setting or within a selected temperature range.

Abstract: A sensor interface assembly is used with a blood pressure measurement device to determine blood pressure of an underlying artery. The sensor interface assembly includes a base unit, a sensing unit and means for detachably connecting the sensing unit to the base unit. The base unit is pivotally attached to the blood pressure measurement device. The sensing unit includes sensing means for sensing blood pressure of each pulse as each pulse travels beneath the sensing means. The means for detachably connecting mechanically and electrically couple the sensing unit to the base unit.

Abstract: A method for biological tissue ablation includes shaping a shapeable RF antenna to accommodate the contour of a body vessel adjacent a biological tissue load; generating a train of radio frequency (RF) energy pulses at an output frequency for transmission in a transmission line to the shapeable RF antenna adjacent the biological tissue load; sensing a reflected signal and a forward signal of the RF energy pulses; and adjusting output frequency of the RF energy pulses to effect a substantial match of transmission line impedance with shapeable RF antenna and biological tissue load impedance.

Abstract: The noninvasive measurement of a patient's blood pressure is achieved automatically in high motion situations by using a dual signal channel pressure sensor in a method and system that acquires pressure waveform data while the degree of compression of an artery is being varied. Two pressure measurement channels are used, one being a main channel for monitoring pressure in the pressure transmission path, and the other being a reference channel for monitoring pressure in a wall through which a holddown force is applied. A caregiver applies the NIBP sensor to the patient. Immediately before the patient is about to engage in high motion activities or be placed in a high motion environment, the caregiver turns ON the automatic HMT function, and proceeds with his or her duties while observing the patient to ensure that the patient is quiet until the NIBP monitor acquires a certain number of waveforms without resetting. Once this has occurred, the caregiver may permit the high motion activity to begin.

Abstract: A RF catheter system includes a catheter with a proximal portion, a distal portion having a distal end and a lumen extending from the proximal portion to the distal portion. Inner and outer coaxially aligned conductors extend within the catheter and are coaxial with the lumen. A deflectable catheter guide is disposed within the catheter lumen and extends proximally within the catheter lumen and terminates distally of the distal end of the catheter to define a biological ablation pathway. A radio-frequency antenna is disposed at the distal portion of the catheter and is in electrical communication with the inner and outer coaxially aligned conductors. The radio-frequency antenna is adaptable to receive and transmit radio-frequency energy for ablating biological tissue along the ablation pathway.

Abstract: A method and apparatus for determining cardiac time intervals that can measure physiological data noninvasively. Arterial pulse values are measured either invasively or noninvasively, from which left ventricular waveform data is generated. Systolic and diastolic time intervals are derived based on the left ventricular waveform data.

Abstract: A preformed catheter set for production of linear ablation lines in the left and right atrium for treatment of atrial fibrillation includes at least a first catheter including a pre-shaped distal segment having a distal linear ablation antenna and a U-shaped curve portion proximal to the distal linear ablation antenna.