Systems and methods for the assessment of cardiac amyloidosis

Patent metadata

Field	Value
Publication number	US-12521078-B2
Application number	US-202217720764-A
Country	US
Kind code	B2
Filing date	Apr 14, 2022
Priority date	Apr 16, 2021
Publication date	Jan 13, 2026
Grant date	Jan 13, 2026

Abstract

Assessment of transthyretin amyloid cardiomyopathy (ATTR-CM) can be performed by calculating a cardiac pyrophosphate activity (CPA) measurement from single-photon emission computed tomography (SPECT) images. SPECT images obtained using 99m Technetium-pyrophosphate as a radiotracer can be analyzed to calculate CPA. Scan-specific thresholds for abnormal myocardial activity are identified based on left ventricular blood pool (LVBP) radiotracer counts, then radiotracer activity in regions of the myocardium with abnormal myocardial activity is determined. Finally, a CPA measurement can be calculated as a function of the mean radiotracer counts in such regions over the maximal LVBP radiotracer activity multiplied by the volume of involvement (e.g., the volume of abnormal activity). This CPA measurement can then be used as an assessment of ATTR-CM.

First claim

What is claimed is:

1 . A system, comprising:
a radio tracer injector; an image scanner operable to sense imaging data of a heart; one or more data processors coupled to the radio tracer injector and the image scanner; and a non-transitory computer-readable storage medium containing instructions which, when executed on the one or more data processors, cause the one or more data processors to perform operations including:
controlling the radio tracer injector to inject a radio tracer in a patient;
activating the image scanner to sense imaging data of a heart;
receiving imaging data of a heart, wherein the imaging data is indicative of a radiotracer uptake in tissue;
determining an abnormal myocardial activity threshold using the imaging data;
identifying a myocardium region of interest in the imaging data;
identifying one or more regions of abnormal myocardial activity within the myocardium region of interest, wherein each of the one or more regions of abnormal myocardial activity has a radiotracer activity greater than the abnormal myocardial activity threshold;
determining a volume of involvement associated with the identified one or more regions of abnormal myocardial activity;
calculating a mean radiotracer activity count for the one or more regions of abnormal myocardial activity; and
calculating a cardiac pyrophosphate activity value using the volume of involvement and the mean radiotracer activity count;
determining a risk of Transthyretin amyloid cardiomyopathy (ATTR-CM) of the heart based on the cardiac pyrophosphate activity value; and
controlling a treatment system to apply a treatment for ATTR-CM from the group consisting of liver transplantation, a therapy stabilizing misfolded transthyretin precursor, or Tafamadis based on the determined risk.

2 . The system of claim 1 , wherein the radiotracer is 99m Technetium-pyrophosphate and the image scanner is a single-photon emission computed tomography scanner.

3 . The system of claim 1 , wherein determining the abnormal myocardial activity threshold includes:
identifying a left ventricular blood pool region of interest (LVBP-ROI) in the imaging data; identifying a maximal radiotracer count within the LVBP-ROI; and calculating the abnormal myocardial activity threshold using the maximal radiotracer count within the LVBP-ROI.

4 . The system of claim 3 , wherein calculating the abnormal myocardial activity threshold using the maximal radiotracer count within the left ventricular blood pool region of interest includes calculating the abnormal myocardial activity threshold as a percentage of the maximal radiotracer count within the left ventricular blood pool region of interest, wherein the percentage is between 125% and 175%.

5 . The system of claim 3 , wherein calculating the cardiac pyrophosphate activity value further uses the maximal radiotracer count within the left ventricular blood pool region of interest.

6 . The system of claim 5 , wherein the cardiac pyrophosphate activity value (CPA) is calculated using the equation

CPA
=

Volume
⁢

of
⁢

Involvement
⁢

x
⁢

mean
⁢

radiotracer
⁢

activity
⁢

count

maximal
⁢

radiotracer
⁢

count
⁢

within
⁢

the
⁢

⁢
LVBP
-
ROI

.

7 . The system of claim 1 , further comprising a display device, wherein the operations further include:
presenting the imaging data on the display device; and presenting the cardiac pyrophosphate activity value on the display device in association with the imaging data and the risk of transthyretin amyloid cardiomyopathy.

8 . A method, comprising:
injecting a radiotracer in tissue; receiving imaging data of a heart from an image scanner, wherein the imaging data is indicative of a radiotracer uptake in tissue; determining an abnormal myocardial activity threshold using the imaging data; identifying a myocardium region of interest in the imaging data; identifying one or more regions of abnormal myocardial activity within the myocardium region of interest, wherein each of the one or more regions of abnormal myocardial activity has a radiotracer activity greater than the abnormal myocardial activity threshold; determining a volume of involvement associated with the identified one or more regions of abnormal myocardial activity via a data processor; calculating a mean radiotracer activity count for the one or more regions of abnormal myocardial activity via the data processor; calculating a cardiac pyrophosphate activity value using the volume of involvement and the mean radiotracer activity count via the data processor; determining a risk of Transthyretin amyloid cardiomyopathy (ATTR-CM) of the heart based on the cardiac pyrophosphate activity value; and applying a treatment for ATTR-CM from the group consisting of liver transplantation, a therapy stabilizing misfolded transthyretin precursor, or treatment with Tafamadis based on the determined risk.

9 . The method of claim 8 , wherein the radiotracer is 99m Technetium-pyrophosphate and the image scanner is a single-photon emission computed tomography scanner.

10 . The method of claim 8 , wherein determining the abnormal myocardial activity threshold includes:
identifying a left ventricular blood pool region of interest (LVBP-ROI) in the imaging data; identifying a maximal radiotracer count within the LVBP-ROI; and calculating the abnormal myocardial activity threshold using the maximal radiotracer count within the LVBP-ROI.

11 . The method of claim 10 , wherein calculating the abnormal myocardial activity threshold using the maximal radiotracer count within the left ventricular blood pool region of interest includes calculating the abnormal myocardial activity threshold as a percentage of the maximal radiotracer count within the left ventricular blood pool region of interest, wherein the percentage is between 125% and 175%.

12 . The method of claim 10 , wherein calculating the cardiac pyrophosphate activity value further uses the maximal radiotracer count within the left ventricular blood pool region of interest.

13 . The method of claim 12 , wherein the cardiac pyrophosphate activity value (CPA) is calculated using the equation

CPA
=

Volume
⁢

Assignees

• Cedars Sinai Medical Center

Inventors

• Slomka Piotr
• Cadet Sebastien
• Kavanagh Paul
• Parekh Tejas

Classifications

• A61B6/5217

  extracting a diagnostic or physiological parameter from medical diagnostic data · CPC title

• A61B6/037 Primary

  Emission tomography · CPC title

• A61B6/469

  for selecting a region of interest [ROI] · CPC title

• A61B6/5235

  combining images from the same or different ionising radiation imaging techniques, e.g. PET and CT · CPC title

• A61B6/032

  Transmission computed tomography [CT] · CPC title