Electrocardiographic measurement method for controlling an intra-aortic balloon pump

• US 4,809,681 A
• Filed: 03/30/1987
• Issued: 03/07/1989
• Est. Priority Date: 03/28/1986
• Status: Expired due to Term

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Suzuki, Akira, Kantrowitz, Adrian, Freed, Paul S., Tachi, Hiroyuki
• Primary Examiner(s): Kamm, William E.
• Application Number:
  US07/031,137
• Time in Patent Office: 708 Days
• Field of Search: 128/1 D, 128/419 P, 128/419 PG, 128/642, 128/695, 128/696, 128/697, 128/708, 128/710, 128/784, 128/788
• US Class Current: 600/17
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/283 Invasive
• CPC Class Codes: A61B 5/6853 with a balloon
• CPC Class Codes: A61M 2205/33 Controlling, regulating or measuring
• CPC Class Codes: A61M 2205/3303 Using a biosensor
• CPC Class Codes: A61M 29/02 Dilators made of swellable material balloon catheters for angioplasty A61M25/104
• CPC Class Codes: A61M 60/139 inside the aorta, e.g. intra-aortic balloon pumps
• CPC Class Codes: A61M 60/295 Balloon pumps for circulatory assistance
• CPC Class Codes: A61M 60/497 for balloon pumps for circulatory assistance
• CPC Class Codes: A61M 60/515 Regulation using real-time patient data

Abstract

A pair of spaced electrodes are disposed inside the thoracic aorta near the heart and are used to sense R- and P-waves in an ECG signal. The electrodes are moved to an ideal intra-aortic position, which is that where R- and P-waves are sensed to have the same magnitude, the P-wave, which occurs earlier than the R-wave, serving as means for accurately predicting the occurrence of the R-wave. The electrodes are affixed to the distal end of an intra-aortic balloon, which is capable of being disposed at the ideal position by monitoring of the R- and P-waves sensed by the electrodes. The balloon is deflated at the occurrence of the R-wave, which has been correctly predicted by the earlier P-wave.

Claims

1. An electrocardiographic measurement method for assistance in controlling deflation of an intra-aortic balloon pump disposed in the thoracic aorta of a patient, comprising the steps of:

disposing at least a pair of spaced electrodes inside the thoracic aorta near the patient'"'"'s heart;

sensing R-waves and P-waves by said electrodes;

moving said electrodes to a position in the thoracic aorta where the R- and P-waves are substantially equal in magnitude for accurately detecting the occurrence of the P-wave;

predicting subsequent occurrences of the R-waves in accordance with the detected occurrences of the P-waves; and

initiating deflation of the intra-aortic balloon pump in accordance with the predicted subsequent occurrences of the R-waves such that the balloon pump is deflated synchronously with each R-wave occurrence.

2. The electrocardiographic method according to claim 1, wherein the step of moving said electrodes include the substeps of:

inserting the electrodes into a deeper region in the thoracic aorta when the R-wave is larger than the P-wave at a first present position in the thoracic aorta;

withdrawing the electrodes into a shallower region in the thoracic aorta when the R-wave and P-wave change polarity at a second present position in the thoracic aorta; and

determining a position intermediate said first and second present positions in the thoracic aorta at which the R- and P-waves are substantially equal in magnitude.