(12) United States Patent ao) Patent No.: us 6,438,409 Bi
Malik et al. (45) Date of Patent: Aug. 20,2002
(54) METHODS OF CHARACTERISING VENTRICULAR OPERATIONS AND APPLICATIONS THEREOF
(75) Inventors: Marek Malik, London (GB); Burak Acar, Ankara (TR); Velislav Nikolaev Batchvarov, London (GB)
(73) Assignee: Medtronic, Inc., Minneapolis, MN (US)
( * ) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.
(21) Appl. No.: 09/534,454
(22) Filed: Mar. 24, 2000
(30) Foreign Application Priority Data
Mar. 25, 1999 (GB) 9906951
Mar. 15, 2000 (GB) 0006235
(51) Int. CI.7 A61B 5/0428
(52) U.S. C I 600/512
(58) Field of Search 600/508, 509,
(56) References Cited
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* cited by examiner
Primary Examiner—Scott M. Getzow
(74) Attorney, Agent, or Firm—Thomas F. Woods; Eric R.
Waldkoetter; Thomas G. Berry
New methods of characterising ventricular operations by measuring propagation characterisics of the repolarisation wavefront (the T wave) are disclosed, the methods use new descriptions of T wave Morphology Dispersion (TMD),
Total Cosin R to T (TCRT) and T wave energy residium
to quantify the wavefront characteristics, these descriptors measure the spatial variability of the T wave Morphology, the vector deviations between the depolarisation and repolarisation wavefronts and the energy of the non-dipolar components of the ECG vector respectively. TCRT also provides a responsive descriptor for measuring autonomic tone. As such, has applications for improved pacing and autonomic nervous system monitors.
41 Claims, 22 Drawing Sheets