A method and system for discriminating ventricular arrhythmia is disclosed. In an embodiment, the method can include implementing an arrhythmia discrimination algorithm that can discriminate between supraventricular tachycardia (SVT) and ventricular tachycardia (VT) using at least one programmable parameter programmed to a first value. The method can include analyzing an SVT event, where analyzing the SVT event can include sensing a physiological signal during the SVT event and identifying characteristics of the sensed physiological signal. The method can further include analyzing a cardiac signal to classify the cardiac signal as either an SVT or a VT using the arrhythmia discrimination algorithm with the programmable parameter (programmed to a second value. The second value can be determined from the identified characteristics of the sensed physiological signal.