Patent ID: 7225014

Claim:
A method comprising: receiving first, second, third and fourth action potential signals sensed at a first myocardial site, each of the first, second, third and fourth action potential signal associated with a respective first, second, third and fourth myocardial contraction; comparing a common characteristic of the first and second action potential signals wherein the common characteristic relates to repolarization of tissue at the myocardial site to determine if alternans exists at the first myocardial site; if alternans exists at the first myocardial site, comparing a common characteristic of the first, second, third and fourth action potential signals, wherein the common characteristic relates to repolarization of tissue at the myocardial site, to determine if the alternans at the first myocardial site is temporally concordant or temporally discordant; and based on whether the alternans at the first myocardial site is concordant or discordant, initiating one or more type of anti-arrhythmia therapy.