Delivery of CRT therapy during AT/AF termination

A method for operating a cardiac rhythm management device, comprising:

• administering a sequential CRT pacing therapy in a sequential CRT pacing mode to a left and right ventricle of a heart of a patient via implanted ventricular electrodes in a sequential bi-ventricular fashion;
• switching from the sequential CRT pacing mode to a modified CRT pacing mode;
• administering a modified CRT pacing therapy in the modified CRT pacing mode, the modified CRT pacing therapy being one of a simultaneous CRT pacing therapy and a single-sided pacing therapy, the simultaneous CRT pacing therapy being administered to the left and right ventricle in a simultaneous bi-ventricular fashion, the single-sided CRT pacing therapy being administered to one of the left and right ventricles;
• and
• administering an atrial electrical stimulation therapy via an implanted atrial electrode to an atrium of the patient in the presence of an atrial arrhythmia.

A system for operating a cardiac rhythm management device, comprising:

• means for sensing atrial depolarizations through an implanted atrial electrode;
• means for administering a sequential CRT pacing therapy in a sequential CRT pacing mode to a left and right ventricle of a heart of a patient via implanted ventricular electrodes in a sequential bi-ventricular fashion;
• means for switching from the sequential CRT pacing mode to a single-sided CRT pacing mode;
• means for administering a single-sided CRT pacing therapy in the single-sided CRT pacing mode to one of the left and right ventricle;
• and
• means for analyzing the sensed atrial depolarizations to detect the presence of an atrial arrhythmia.