The primary objective is to determine the effect of tHGNS on tongue position in the upper airway in subjects undergoing an EP, cardiac catheterization or device procedure. (Measured as changes in the anteroposterior dimensions (2-dimensional) of the retropalatal and retrolingual airway spaces.) This will be an acute study lasting no more than 45 min during a standard new device implant, cardiac catheterization and/or EP procedure. The hypoglossal nerve will be stimulated from the lingual vein using various stimulation parameters. Tongue motion, upper airway opening or any side effects will be recorded. At the end of the test procedure all hardware - the catheters, lead and/or guide wire will be removed.