United States Patent [19] [li] Patent Number: 4,708,142
DeCote, Jr. [45] Date of Patent: Nov. 24,1987
U. S. Patent Nov. 24,1987 Sheet 1 of3 4,708,142
[54] AUTOMATIC CARDIAC CAPTURE
THRESHOLD DETERMINATION SYSTEM
AND METHOD
[75] Inventor: Robert DeCote, Jr., Miami Beach, Fla.
[73] Assignee: Cordis Corporation, Miami, Fla.
[21] Appl. No.: 738,609
[22] Filed: May 28, 1985
[51] Int. CI.4 A61N 1/36
[52] U.S. CI 128/419 PT
[58] Field of Search 128/419 PG, 419 PT
[56] References Cited
U.S. PATENT DOCUMENTS
3,683,934 8/1972 Bukowiecki et al 128/419 PG
3,757,790 9/1973 Herrmann 128/419 PT
3,777,762 12/1973 Nielsen 128/419 PT
3,800,801 4/1974 Gaillard 128/419 PT
3,949,758 4/1976 Jirak 128/419 PG
4,245,643 1/1981 Benzing, III et al 128/419 PT
4,290,430 9/1981 Bihn et al 128/419 PT
4,337,776 7/1982 Daly et al 128/419 PT
OTHER PUBLICATIONS
A New Electronic System for the Detection of the Stimulated Cardiac Response, J. Mugica, B. Lazarus, D. Delle-Vedove, Y. Lallemand, O. Hubert.
Primary Examiner—William E. Kamm
Attorney, Agent, or Firm—Lockwood, Alex, FitzGibbon
& Cummings
[57] ABSTRACT
An automatic capture threshold determination system and method apply pacing pulses to a patient's heart while simultaneously monitoring intracardiac electrical activity to detect evoked cardiac contractions. The system and method automatically adjust the energy of the applied pacing pulses in accordance with a prearranged routine, until capture is obtained, thereby determining the minimum pulse amplitude required to reliably stimulate the heart.
11 Claims, 5 Drawing Figures
