Abstract: Methods and systems of catheterization include a flexible catheter adapted for insertion into a heart of a living subject. The catheter has a lumen for passing an electrically conductive fluid therethrough with the fluid exiting the catheter at the distal portion. The lumen is connectable to an irrigation pump to form a fluid communication therewith. A fluid reservoir connected to the lumen supplies the fluid to the catheter. Electrocardiogram circuitry is connectable to the subject for monitoring electrical activity in the heart. An electrically conductive cable diverts induced charges in the fluid from the catheter electrodes, for example by connection to an isolated ground of the electrocardiogram.

Abstract: A catheter has an inflatable assembly at its distal portion, including a containment chamber, an axial core and a plurality of longitudinally oriented partitions extending from the axial core to the wall of the chamber to divide the containment chamber into at least four inflatable sectors. Hydraulic valves are connected to respective sectors to enable selective inflation of the sectors by a fluid when the valves are connected to a source of the fluid, and at least one surface electrode is mounted on each of the sectors. When introduced into a heart chamber and diametrically opposed sectors are inflated the assembly is stably fixed against the walls of the heart chamber and readings can be obtained from the surface electrodes of the inflated sectors.

Abstract: A method includes, while an operator of an elongated probe, having proximal and distal ends, manipulates the proximal end so as to move the distal end within a body of a patient, automatically measuring a cumulative angle of rotation that is applied by the operator to the proximal end. An indication of the cumulative angle of rotation is presented to the operator.

Abstract: A catheter has an inflatable assembly at its distal portion, including a containment chamber, an axial core and a plurality of longitudinally oriented partitions extending from the axial core to the wall of the chamber to divide the containment chamber into at least four inflatable sectors. Hydraulic valves are connected to respective sectors to enable selective inflation of the sectors by a fluid when the valves are connected to a source of the fluid, and at least one surface electrode is mounted on each of the sectors. When introduced into a heart chamber and diametrically opposed sectors are inflated the assembly is stably fixed against the walls of the heart chamber and readings can be obtained from the surface electrodes of the inflated sectors.

Abstract: An apparatus, including an insertion tube having a proximal tube end and a distal tube end that includes an electrode, a first irrigation line including proximal and distal irrigation line ends and configured to supply fluid from the distal irrigation line end through apertures in the tube, and an electrical line including a proximal electrical line end and a distal electric line end coupled to the electrode. The apparatus includes a slip ring unit having a stator, a rotor connected to the proximal electrical line end, and a hollow channel extending through respective centers of the stator and the rotor along a longitudinal axis of the slip ring unit. The apparatus includes a rotary joint in fluid communication with the proximal irrigation line end, an angle sensor configured to detect torsion of the proximal irrigation line end, and a drive mechanism coupled to rotate the rotor responsively to the torsion.

Abstract: A flexible catheter has an ablation electrode disposed in its distal segment. The ablation electrode a cavity formed in its external surface, a microelectrode configured to fit into the cavity, a conductive wire lead connecting the microelectrode to receiving circuitry, and an electrical shield surrounding the wire lead. A power generator is connected to the ablation electrode and the electrical shield in a generator circuit. A back patch electrode adapted to contact with the subject is connected in the generator circuit. The microelectrodes can be active while energizing the ablation electrode.

Abstract: A method includes, while an operator of an elongated probe, having proximal and distal ends, manipulates the proximal end so as to move the distal end within a body of a patient, automatically measuring a cumulative angle of rotation that is applied by the operator to the proximal end. An indication of the cumulative angle of rotation is presented to the operator.

Abstract: A device for gripping a catheter, including a first jaw having a first exterior side and a first radial passage. The device has a second jaw having a second exterior side, opposite the first exterior side, and a second radial passage. The device also has a resilient joint connecting the first and second jaws so that manual compression of the first exterior side toward the second exterior side causes relative rotation between the first and second jaws that mutually aligns the first and second radial passages, such that the catheter can be inserted through the first and second radial passages, and so that releasing the manual compression causes the first and second jaws to rotate so that the first and second radial passages are no longer mutually aligned and so that the catheter passes through and is gripped by the device along mutually aligned first and second central axes.

Abstract: Catheterization employing a cable extending from the catheter to a fixed point of attachment is performed by providing a sensor to detect rotation of the catheter about its longitudinal axis, the rotation causing the cable to form a twist. The cable extends through a cable arranger that operates to remove the twist. A controller receives signals from the sensor and generates control signals to actuate the cable arranger responsively to the signals from the sensor.

Abstract: An apparatus, including an insertion tube having a proximal tube end and a distal tube end that includes an electrode, a first irrigation line including proximal and distal irrigation line ends and configured to supply fluid from the distal irrigation line end through apertures in the tube, and an electrical line including a proximal electrical line end and a distal electric line end coupled to the electrode. The apparatus includes a slip ring unit having a stator, a rotor connected to the proximal electrical line end, and a hollow channel extending through respective centers of the stator and the rotor along a longitudinal axis of the slip ring unit. The apparatus includes a rotary joint in fluid communication with the proximal irrigation line end, an angle sensor configured to detect torsion of the proximal irrigation line end, and a drive mechanism coupled to rotate the rotor responsively to the torsion.

Abstract: A catheter has an inflatable assembly at its distal portion, including a containment chamber, an axial core and a plurality of longitudinally oriented partitions extending from the axial core to the wall of the chamber to divide the containment chamber into at least four inflatable sectors. Hydraulic valves are connected to respective sectors to enable selective inflation of the sectors by a fluid when the valves are connected to a source of the fluid, and at least one surface electrode is mounted on each of the sectors. When introduced into a heart chamber and diametrically opposed sectors are inflated the assembly is stably fixed against the walls of the heart chamber and readings can be obtained from the surface electrodes of the inflated sectors.

Abstract: A sheath includes an elongate tube, which has an outer wall that surrounds an inner lumen and has multiple holes along the tube penetrating the outer wall. Multiple electrically-conducting elements are inserted in the respective holes, so as to allow transmission of electrical current between the inner lumen and an exterior of the outer wall.

Abstract: A probe, consisting of a flexible insertion tube, for insertion into a subject via a body lumen. The probe includes a sequence of tubular modules contained within the insertion tube, each module having a rigid tube segment having a preset shape and containing internal grooves on an interior surface of the tube segment. The probe further includes a flexible expander tube, which is threaded through the sequence of tubular modules and has external grooves configured to engage the internal grooves within the tube segment of each of the tubular modules when the expander tube is expanded, so as to hold the tubular modules in mutual alignment, wherein the tubular modules are able to move out of mutual alignment when the expander tube is unexpanded. The probe also has an expansion element, which is insertable through the flexible expander tube so as to expand the expander tube.

Abstract: Methods and systems of catheterization include a flexible catheter adapted for insertion into a heart of a living subject. The catheter has a lumen for passing an electrically conductive fluid therethrough with the fluid exiting the catheter at the distal portion. The lumen is connectable to an irrigation pump to form a fluid communication therewith. A fluid reservoir connected to the lumen supplies the fluid to the catheter. Electrocardiogram circuitry is connectable to the subject for monitoring electrical activity in the heart. An electrically conductive cable diverts induced charges in the fluid from the catheter electrodes, for example by connection to an isolated ground of the electrocardiogram.

Abstract: Apparatus, which consists of a plurality of modules. Each of the modules has: an insulating frame, a pair of electrodes fixed to the frame at respective locations that are spaced apart, and circuitry configured to receive signals from the pair of electrodes and in response output a differential signal. The apparatus further consists of an insertion tube having distal and proximal ends and containing the plurality of modules in locations spaced longitudinally in proximity to the distal end. There is cabling running through the tube that is connected to convey differential signals from the modules to the proximal end.

Abstract: A method, including generating a three-dimensional (3D) map as a plurality of points illustrating a characteristic of a 3D heart chamber, the 3D heart chamber having an opening bounded by a perimeter. The method further includes transforming the perimeter into a closed two-dimensional (2D) figure having an interior. The plurality of points illustrating the characteristic are projected onto the interior of the 2D figure so as to generate a 2D map of the characteristic of the 3D heart chamber.

Abstract: A method for position sensing includes inserting a probe having a first probe-electrode and a second probe-electrode into a body of a subject, and coupling body-surface electrodes to a surface of the body. Currents passing between the first probe-electrode and the body-surface electrodes are measured, using first circuitry coupled to at least the first probe-electrode and having a first electrical ground, and position coordinates of the probe are determined responsively to the measured currents. Second circuitry, having a second electrical ground, is coupled to at least the second probe-electrode, and the first electrical ground is isolated from the second electrical ground.

Abstract: An apparatus includes a sensing unit and control circuitry. The sensing unit is connected to a channel that delivers Electro-Physiological (EP) signals from a cardiac catheter to an EP recording system and pacing signals from the EP recording system to the catheter. The sensing unit is configured to automatically identify time intervals during which the pacing signals are delivered. The control circuitry is configured to route the EP signals on the channel from the catheter to the EP recording system via an intervening system that is detrimental to the pacing signals, to switch the channel to an alternate path that bypasses the intervening system during the identified time intervals, and to route the pacing signals from the EP recording system to the cardiac catheter over the alternate path.

Abstract: An apparatus includes a sensing unit and control circuitry. The sensing unit is connected to a channel that delivers Electro-Physiological (EP) signals from a cardiac catheter to an EP recording system and pacing signals from the EP recording system to the catheter. The sensing unit is configured to automatically identify time intervals during which the pacing signals are delivered. The control circuitry is configured to route the EP signals on the channel from the catheter to the EP recording system via an intervening system that is detrimental to the pacing signals, to switch the channel to an alternate path that bypasses the intervening system during the identified time intervals, and to route the pacing signals from the EP recording system to the cardiac catheter over the alternate path.

Abstract: A method includes, while an operator of an elongated probe, having proximal and distal ends, manipulates the proximal end so as to move the distal end within a body of a patient, automatically measuring a cumulative angle of rotation that is applied by the operator to the proximal end. An indication of the cumulative angle of rotation is presented to the operator.