Patent ID: 6179865
Filing Date: 2001-01-30
Classification: A61N

Abstract:
A method comprising:sensing atrial contractions and ventricular contractions;determining atrial cycle lengths from sensed atrial contractions, where an atrial cycle length is a time between a first atrial contraction which starts the atrial cycle length and a second atrial contraction which ends the atria cycle length;determining ventricular cycle lengths from sensed ventricular contractions, where a ventricular cycle length is a time between a first ventricular contraction which starts the ventricular cycle length and a second ventricular contraction which ends the ventricular cycle length;analyzing ventricular contractions for the occurrence of a tachycardia episode that has a one-to-one association of atrial contractions to ventricular contractions;during the tachycardia episode that has the one-to-one association of atrial contractions to ventricular contractions, pairing the atrial cycle lengths with the ventricular cycle lengths, where for each of the atrial cycle lengths the atrial cycle length is paired with at least one ventricular cycle length started before the first atrial contraction of each of the atrial cycle lengths and paired with at least one ventricular cycle length started after the first atrial contraction of each of the atrial cycle lengths;determining a retrograde correlation coefficient for the atrial cycle lengths paired with the ventricular cycle lengths started before the first atrial contraction;determining an antegrade correlation coefficient for the atrial cycle lengths paired with the ventricular cycle lengths started after the first atrial contraction; andclassifying the tachycardia episode based on a comparison of the antegrade correlation coefficient and the retrograde correlation coefficient.