Patent ID: 8412321

Claim:
A system for use in identifying treatment therapies as therapeutic strategies for preventing ventricular tachycardia from developing into ventricular fibrillation, said system comprising: a medical device programmed to detect ventricular tachycardia in a subject; monitor intervals between electrical stimuli in the heart of the subject; determine if an initial 3 stimuli in groups of 4 stimuli from said monitoring in the heart correspond to rest interval values (I) predicted to lead to ventricular fibrillation as defined by a first equation as follows: I n + 1 ⁡ ( x i ) = τ + ∑ j = 0 i - 1 ⁢ Δ ⁢ ⁢ x c ⁡ ( I n + 1 ⁡ ( x j ) ) - ∑ j = 0 i - 1 ⁢ Δ ⁢ ⁢ x c ⁡ ( I n ⁡ ( x j ) ) - D n + 1 ⁡ ( x i ) , wherein τ is a time interval between activations applied to a pacing site (x i ), Δx is 0.1, I n+1 (x j ) is a rest interval value of the n+1th action potential at a pacing site (x j ), I n (x j ) is a rest interval value of an nth action potential at a pacing site (x j ), D n+1 (x i ) is an action potential duration of an n+1th action potential at pacing site (x i ), c is a velocity recovery function of I n (x j ) and I n+1 (x j ), respectively; identify treatment therapies which prevent occurrence of a fourth stimuli corresponding to the rest interval values; and identify treatment therapies which prevent said ventricular tachycardia from becoming ventricular fibrillation as therapeutic strategies for prevention of ventricular fibrillation.