Ambulatory physiological evaluation system including cardiac monitoring

• US 5,111,818 A
• Filed: 05/08/1990
• Issued: 05/12/1992
• Est. Priority Date: 10/08/1985
• Status: Expired due to Term

• Current Assignee: Capintec, Inc. (American Capital Limited)
• Original Assignee: Capintec, Inc. (American Capital Limited)
• Inventors: Suzuki, Arata, Suzuki, Marcia, Tyberg, William T., Banks, George
• Primary Examiner(s): JAWORSKI, FRANCIS J
• Application Number:
  US07/520,405
• Time in Patent Office: 735 Days
• Field of Search: 128/644, 128/641, 128/659, 128/721, 128/733, 128/736, 128/653
• US Class Current: 600/390
• CPC Class Codes: A61B 5/02755 Radioactive tracers
• CPC Class Codes: A61B 5/336 Magnetic recording apparatus
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/6805 Vests

Abstract

An ambulatory physiological evaluation system including a main and background gamma radiation detector provided in a vestlike garment worn by a patient for the purpose of monitoring and/or diagnosing the patient'"'"'s physiological activities during a prescribed period of time. Also included is an apparatus and method for determining the exact location of the left ventricle of the heart, positioning the main radiation detector relative to the left ventricle, and maintaining the position of the main radiation detector relative to the left ventricle during an ambulatory study period. The ambulatory physiological evaluation system also contains electronic circuitry which monitors and processses information obtained from the radiation detectors. Information from the main and auxiliary detectors, as well as ECG electrodes is recorded on a portable cassette recorder. After the information has been recorded over a desired period of time, the information is presented, through an interface and an analog to digital converter, to the memory of a stand alone computer located in a hospital or office. The computer calculates such items as R-R time intervals, electrocardiagram and time-activity curves, and displays these items and other physiological data for both the main and auxiliary detectors. From the calculations made by the computer, average heart rate, number of aberrant beats, left ventricular ejection fraction and relative cardiac blood volume and other values of physiological significance may be calculated for a time interval of interest.

Claims

1. Apparatus for aligning a radiation detector relative to the left ventricle of the heart of a patient, said apparatus comprising:

a vest adapted to be worn about the torso of the patient and covering the heart;

a mounting bracket to be mounted to said vest and to receive said radiation detector;

a first mounting means for adjustably mounting said bracket relative to said vest;

a planar alignment fixture having a centerline cursor made from elements that do not pass gamma radiation;

registration means for aligning said alignment fixture in a predetermine position on said mounting bracket; and

means for fixedly mounting said alignment fixture to said mounting bracket.

2. The apparatus of claim 1, wherein said mounting bracket comprises:

first and second spaced planar flanges each of said flanges having a surface contacting said vest when said bracket is mounted to said vest;

at least one elongated slot defined in each of said flanges, the longitudinal axis of said elongated slots of each flange being essentially parallel to each other; and

complementary elongated slots defined on said vest so that when said mounting bracket is mounted on said vest, said elongated slots and said complementary slots are in a mating relationship with one of said elongated slots of said bracket overlapping one of said complementary slots.

3. The apparatus of claim 2, wherein said overlapping slots are arranged so that the longitudinal axis of said slot of said bracket is substantially perpendicular to the axis of said complementary slot.

4. The apparatus of claim 1, wherein said means for fixedly mounting includes a base plate that is also used for mounting said radiation detector.

5. A method for aligning a radiation detector relative to the left ventricle of the heart of a patient, said method comprising the steps of:

causing the patient to wear a perforated vest that covers the heart;

mounting for further adjustment a mounting bracket to the vest, the mounting bracket including an surface for receiving the radiation detector;

mounting an alignment fixture having a centerline cursor to the area of the mounting bracket that receives the radiation detector, the centerline cursor being made from elements that do not pass gamma radiation;

aligning a Gamma camera with the alignment fixture and the left ventricle of the heart;

observing the image produced by the Gamma camera to determine if the centerline is within a predetermined distance of a desired portion of the left ventricle of the heart;

adjusting the mounting bracket until the centerline is within the predetermined distance;

fixing the mounting bracket to the vest when the centerline is within the predetermined distance;

removing the alignment fixture after the mounting bracket has been fixedly mounted to the vest; and

attaching the radiation detector to said mounting bracket after the alignment fixture has been removed.

6. The method of claim 5, further comprising the steps of aligning the Gamma camera so that the focal plane of the camera is generally parallel to the intended position of the detecting plane of the radiation detector when the detector is mounted on the mounting bracket.

7. The method of claim 5, further comprising the steps of aligning the Gamma camera so that the focal plane of the camera is generally parallel to the surface of the mounting bracket where the radiation detector is to be mounted.

8. The method of claim 5, further comprising the steps of mounting the bracket so that the surface for receiving the radiation detector is placed in the left anterior oblique position on the body of the patient.

9. A mounting bracket structure for use on a chest encompassing vest for securing a heart function monitoring device over a patient'"'"'s heart, the structure including:

base plate means including flange means for adjustable attachment to said vest and a substantially planar base plate portion between the flange means;

a mounting plate, securement means for releasably attaching the mounting plate on the base portion,

a retainer means for locating a swiveling ball socket on the mounting plate, a ball socket mounted in said retaining means for swiveling and rotational movements, wherein the retainer means includes a circumferentially extending series of flexible socket-receiving fingers;

clamping means associated with the retainer means for releasably locking the ball socket against said swiveling and rotational movement;

wherein the clamping means includes;

a tightening strap encircling the fingers; and

a toggle-type over-center lever for tightening the strap around the fingers to lock the socket against swiveling and rotational movements in the retainer means; and

latching means within the ball socket for releasably and selectively receiving therein a plug portion of an alignment fixture for setting the position of the ball socket relative to the patient'"'"'s heart and the plug portion of a heart monitoring device.

10. A mounting bracket structure for use on a chest encompassing vest for securing a heart function monitoring device over a patient'"'"'s heart, the structure including:

base plate means including flange means for adjustable attachment to said vest and a substantially planar base plate portion between the flange means;

a mounting plate, securement means for releasably attaching the mounting plate, a ball socket mounted in said retaining means for swiveling and rotational movements;

clamping means associated with the retainer means for releasably locking the ball socket against said swiveling and rotational movements; and

latching means within the ball socket for releasably and selectively receiving therein a plug portion of an alignment fixture for setting the position of the ball socket relative to the patient'"'"'s heart and the plug portion of a heart monitoring device wherein the latching means comprises

female bayonet-type fitting means in the ball socket for receiving complimentary male bayonet-type fitting means on the respective plug portions.

11. The structure as defined in claim 10 wherein the female bayonet-type fitting means comprises:

a circumferential rebated groove in an internal wall of the ball socket toward an inner end of the socket;

a spring thrust washer in the groove; and

axially extending channels formed in said wall leading from an outer end of the socket into said groove, the male bayonet-type fitting means comprising projecting tab means on the respective plug portions for receipt in said channels.