Simultaneous cardiac pacing and local drug delivery method

• US 5,634,899 A
• Filed: 01/04/1994
• Issued: 06/03/1997
• Est. Priority Date: 08/20/1993
• Status: Expired due to Term

• Current Assignee: Vention Medical Advanced Components, Inc. (Nordson Corporation)
• Original Assignee: Cortrak Medical Incorporated
• Inventors: Hildebrand, Keith R., Shapland, James E.
• Primary Examiner(s): Green, Randall L.
• Assistant Examiner(s): Bockelman, Mark
• Application Number:
  US08/177,175
• Time in Patent Office: 1,246 Days
• Field of Search: 607/120, 607/129, 607/27, 607/30, 607/124, 607/122, 604/20, 604/21, 604/53, 604/51, 604/50
• US Class Current: 604/507
• CPC Class Codes: A61M 2025/0057 Catheters delivering medicament other than through a conventional lumen, e.g. porous walls or hydrogel coatings
• CPC Class Codes: A61M 25/104 used for angioplasty
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: A61N 1/0568 with drug delivery
• CPC Class Codes: A61N 1/306 Arrangements where at least part of the apparatus is introduced into the body
• CPC Class Codes: A61N 1/325 for iontophoresis, i.e. transfer of media in ionic state by an electromotoric force into the body electrodes for external use A61N1/0428
• CPC Class Codes: A61N 1/327 for enhancing the absorption properties of tissue, e.g. by electroporation
• CPC Class Codes: A61N 1/3629 in combination with non-electric therapy

Abstract

An apparatus and method for delivering a drug selectively and locally to internal body tissue with a catheter using electric current/voltage controlled in conjunction with active pacing of cardiac activity.

Claims

1. A method of delivering a drug to internal body tissue of a patient using a catheter that is configured to deliver drugs, said catheter being connected to a plurality of electrodes, said method comprising the steps of:

(a) inserting said catheter into a body lumen so that at least a first electrode is proximate said internal body tissue;

(b) positioning other of said plurality of electrodes with respect to the first whereby cardiac pacing and drug delivery into said internal body tissue may be performed;

(c) providing a drug adjacent said first electrode;

(d) supplying a pacing pulse between at least two of said electrodes initiating at least one cardiac cycle;

(e) supplying drug delivery current/voltage between at least two of said electrodes including said first electrode to deliver said drug to said internal body tissue; and

(f) synchronizing the current/voltage to the pacing pulse to deliver drug in a predetermined manner within the remaining portion of the cardiac cycle to reduce the risk of inducing arrhythmia.

2. The method of claim 1, wherein said step of supplying drug delivery current/voltage further comprises supplying said drug delivery current/voltage as a pulsed waveform with a frequency of at least about 200 Hz.

3. The method of claim 2, wherein said frequency is at least about 2 kHz.

4. The method of claim 1 wherein the step of supplying drug delivery current/voltage occurs after the step of supplying a pacing pulse and before the patient'"'"'s heart begins to repolarize.

5. The method of claim 1 wherein the duration of the pacing pulse is in the range of about 0.5 to about 5 milliseconds.

6. The apparatus of claim 1 wherein the step of supplying drug delivery current/voltage includes the step of iontophoretically delivering drug from said catheter to said internal body tissue.

7. The method of claim 1 wherein the step of supplying drug delivery current/voltage includes the step of electroporating cells of the internal body tissue.

8. The method of claim 1 wherein the patient'"'"'s heartbeat has a repolarization phase, the method comprising the additional step of adjusting the drug delivery current/voltage from a first predetermined amplitude to a second predetermined amplitude during the repolarization phase, thereby minimizing the risk of inducing arrhythmia.

9. The method of claim 1 wherein the heart senses intrinsic electrical activity that has a first frequency, further wherein the step of supplying a pacing pulse includes the step of supplying a plurality of pacing pulses at a second frequency that is greater than the first frequency.

10. The method of claim 1 wherein the heartbeat has a repolarization phase, further wherein the pacing pulse is supplied at a time that does not correspond to the repolarization phase of the heartbeat.

11. The method of claim 1 wherein the heartbeat has a period of ventricular depolarization and the catheter further comprises a sensor, further wherein the step of supplying a pacing pulse is performed by supplying a pulse train, the pulse train having a predetermined frequency, the method comprising the additional step of resetting the pulse train upon sensing ventricular depolarization.