Abstract: Computer-implemented methods of predicting the QTc of a subject in response to administration of QTc prolonging drugs, especially those that are dose adjusted for renal function, such as antiarrhythmic drugs. Included is a method of administering an antiarrhythmic drug to a subject, comprising: providing as inputs into a treatment management application i) Baseline QTc and ii) at least a Creatinine Clearance, Weight, Age, Sex, or Heart Rate; the treatment management application providing as an output one or more predicted QTc or predicted QTc range for the subject expected from administration of a 1-5 hour IV dose, alone or followed by one or more oral doses, of an antiarrhythmic drug to the subject; and upon the one or more QTc or QTc range being within an acceptable range, administering the 1-5 hour IV dose to the subject optionally followed by administering one or more of the oral doses to the subject.

Abstract: A system and method for selectively treating a ventricular tachycardia based on sensed atrial and ventricular intervals from the patient's heart. A detection window of the ten most recent atrial and ventricular intervals are analyzed for the occurrence of either tachycardia or fibrillation. When a majority of the sensed intervals are satisfied, the apparatus starts a duration time interval. Ventricular intervals and atrial intervals are compare, ventricular interval greater than the atrial interval by a bias factor the system delivers tachycardia therapy to the heart. Alternatively, the method withholds tachycardia therapy to the heart when the atrial rate is classified as atrial fibrillation and the ventricular response is unstable.