Abstract: A method includes providing an elongated probe having a longitudinal axis and a distal end, and capable of rotation of the distal end about the longitudinal axis in mutually opposite first and second directions. While an operator manipulates the probe within a body of a patient, the rotation that is applied to the distal end is sensed automatically. An alert is issued to the operator upon sensing that the rotation is in the second direction, but not when the sensed rotation is in the first direction.

Abstract: Methods and systems for mapping cardiac electrical activity employ a cardiac catheter having a plurality of spines mounted at the distal end, each spine having a plurality of electrodes. Electrical signal data are obtained from the heart via the electrodes, and respective intracardiac locations and orientations of the spines are sensed. An electroanatomic map of the heart is derived from the signal data, and presented as a graphic representation of the respective intracardiac locations and orientations of the spines, with distinctive graphical indicia of at least portions of the spines. The method is further carried out by displaying the electroanatomic map, and responsively to the displayed electroanatomic map, adjusting at least one of the locations and orientations of at least one of the spines.

Abstract: A method includes providing an elongated probe having a longitudinal axis and a distal end, and capable of rotation of the distal end about the longitudinal axis in mutually opposite first and second directions. While an operator manipulates the probe within a body of a patient, the rotation that is applied to the distal end is sensed automatically. An alert is issued to the operator upon sensing that the rotation is in the second direction, but not when the sensed rotation is in the first direction.