Patent ID: 7167745

Claim:
A method of deriving spatial and/or temporal distributions of action potentials across a heart, comprising: determining a T-wave alternan waveform by (a) differencing a plurality of temporally adjacent T-wave segments to obtain preliminary alternan waveforms, (b) compensating for disturbances and/or ectopic beats in the preliminary alternan waveforms, and (c) computing a final alternan waveform; and decomposing the final alternan waveform to provide information relating to changes in cardiac action potentials of the subject, wherein decomposing the final alternan waveform comprises fitting the final alternan waveform with a summation of a plurality of alternan model curves, with individual alternan model curves being associated with a specific phase of the cardiac action potential and scaled in amplitude such that a difference between the final alternan waveform and the summation is reduced.