Patent ID: 7039463
Filing Date: 2006-05-02
Classification: A61B,A61N

Abstract:
1. A system, comprising: means for sampling a normal sinus rhythm (NSR) QRS-complex from a NSR cardiac cycle; means for locating a plurality of feature points on the NSR QRS-complex based on morphological features of the NSR QRS-complex; means for determining a NSR template for a plurality of the NSR cardiac cycles, wherein the NSR template includes a median value for each of the plurality of feature points; means for producing a NSR filter output from a numerical convolution of the NSR template and the plurality of feature points for each of the plurality of the NSR cardiac cycles; means for determining a median NSR filter output template for the plurality of the NSR cardiac cycles, wherein the median NSR filter output template has a median value for each value in the NSR filter output; means for detecting a tachycardia event; means for sampling a QRS-complex from a tachycardia complex during the tachycardia event; means for locating the plurality of feature points on the QRS-complex from the tachycardia complex based on morphological features of the QRS-complex; means for producing a tachycardia complex output from a numerical convolution of the NSR template with the plurality of feature points on the QRS-complex from the tachycardia complex; means for summing a numerical difference between the values of the tachycardia complex output and the median NSR filter output template; and means for classifying the tachycardia complex as a ventricular tachycardia complex when the sum of the difference between the values of the tachycardia complex output and the median NSR filter output template is greater than or equal to a predetermined sum of residual threshold value.