Method and apparatus for controlling the base frequency of a cardiac pacemaker

United States Patent m

Limousin et al.

[54] METHOD AND APPARATUS FOR

CONTROLLING THE BASE FREQUENCY OF
A CARDIAC PACEMAKER

[75] Inventors: Marcel Limousin, Montrouge;

Jean-Luc Bonnet, Vanves; Anne
Bouhour, Paris, all of France

[73] Assignee: ELA Medical S.A., Montrouge, France

[21] Appl. No.: 405,286

[22] Filed: Mar. 16, 1995

[30] Foreign Application Priority Data

Mar. 16, 1994 [FR] France 94 3039

[51] Int CI.6 A61N 1/36; A61N 1/365

[52] U.S. CI 607/19; 607/25

[58] Field of Search 607/19, 25

[56] References Cited

U.S. PATENT DOCUMENTS

4,428,378 1/1984 Anderson et al 607/19

4,712,556 12/1987 Baker, Jr. 128/419 PG

4,856,523 8/1989 Sholderetal 607/17

4,892,100 1/1990 Schaldach 607/19

4,926,863 5/1990 Alt 607/19

5,040,534 8/1991 Mannetal 607/19

5,044,365 9/1991 Webbetal 607/19

5,143,065 9/1992 Adkinsetal 607/19

5,215,084 6/1993 Schaldach 607/19

5,249,572 10/1993 Bonnet 607/20

532,839 2/1994 Rolineetal 607/19

iniiiiiiiiiiiiii

US005645576A

[ii] Patent Number: 5,645,576 [45] Date of Patent: Jul. 8, 1997

5,300,092 4/1994 Schaldach 607/19

5,303,702 4/1994 Bonnet et al 607/20

5,312,451 5/1994 Limousin et al 607/15

5,330,510 7/1994 Legayetal 607/19

5,417,715 5/1995 Noren et al 607/9

5,447,524 9/1995 Alt 607/19

5,514,162 5/1996 Bomzinetal 607/19

FOREIGN PATENT DOCUMENTS

080348 11/1982 European Pat. Off. A61N 1/365

203027 2/1986 European Pat. Off. A61N 1/365

326629 2/1988 European Pat. Off. A61N 1/365

313881 10/1988 European Pat. Off. A61N 1/365

493220A1 12/1991 European Pat. Off. A61N 1/365

WO86/07270 12/1986 WIPO A61N 1/36

WO91/01157 2/1991 WIPO A61N 1/365

Primary Examiner—William E. Kamm

Assistant Examiner—Carl H. Layno

Attorney, Agent, or Firm—Orrick, Herrington & Sutcliffe,

LLP

[57] ABSTRACT

Process of control of the base frequency of a cardiac pacemaker having at least one sensor monitoring a physiological parameter. Rest phases and resumption of activity phases are detected to adapt automatically the base frequency of the pacemaker to the relative periods of rest and activity of the patient. Thus, the base frequency is allowed to decrease below the normally programmed base frequency in response to actual patient rest, to encourage a low spontaneous cardiac rhythm to inhibit pacing.

48 Claims, 3 Drawing Sheets

FBASE PROG ^

■ ** *

FBASE MIN