Method and apparatus for detecting and discriminating tachycardia

A medical device for discriminating cardiac events, comprising:

• a plurality of electrodes configured to sense cardiac signals along a first sensing vector and a second sensing vector different from the first sensing vector;
• and
• a processor configured to determine a first match score corresponding to a first cardiac signal sensed along the first sensing vector, determine whether the first match score is within a first match zone having a first correlation with a non-treatable cardiac event, a second match zone having a second correlation with the non-treatable cardiac event less than the first correlation with the non-treatable event, a third match zone having a first correlation with a treatable cardiac event, and a fourth match zone having a second correlation with the treatable cardiac event greater than the first correlation with the treatable cardiac event, determine, in response to the first match score being within one of the second match zone and the third match zone, a second match score corresponding to a second cardiac signal sensed along the first sensing vector and a third match score corresponding to a third cardiac signal sensed along the second sensing vector, determine whether the second match score and the third match score are within the first match zone, the second match zone, the third match zone and the fourth match zone to generate a first adjusting factor, accumulate cardiac event evidence in response to the first adjusting factor, and discriminate cardiac events in response to the accumulated cardiac evidence.

A non-transitory computer readable medium having computer executable instructions for performing a method, the method comprising:

• sensing cardiac signals along a first sensing vector and a second sensing vector different from the first sensing vector;
• determining a first match score corresponding to a first cardiac signal sensed along the first sensing vector;
• determining whether the first match score is within a first match zone having a first correlation with a non-treatable cardiac event, a second match zone having a second correlation with the non-treatable cardiac event less than the first correlation with the non-treatable event, a third match zone having a first correlation with a treatable cardiac event, and a fourth match zone having a second correlation with the treatable cardiac event greater than the first correlation with the treatable cardiac event;
• determining, in response to the first match score being within one of the second match zone and the third match zone, a second match score corresponding to a second cardiac signal sensed along the first sensing vector and a third match score corresponding to a third cardiac signal sensed along the second sensing vector;
• determining whether the second match score and the third match score are within the first match zone, the second match zone, the third match zone and the fourth match zone to generate a first adjusting factor;
• accumulating cardiac event evidence in response to the first adjusting factor;
• and
• discriminating cardiac events in response to the accumulated cardiac evidence.