1：Experimental Design and Method Selection:

The MVAD? pump was tested for interaction with radiotracers in an in vitro ?ow-loop study. The radiotracers 18F-sodium ?uoride and 18F-FDG were injected into a closed loop to determine the feasibility of direct imaging of the MVAD? pump in a PET scanner.

2：Sample Selection and Data Sources:

An MVAD? pump with an attached 10 mm out?ow graft was connected to a

3：2 L in vitro ?ow loop ?lled with deionized water and glycerin at a

1 ratio.

4：List of Experimental Equipment and Materials:

A microPET R4 scanner (Siemens) with a

5：8 mm spatial resolution at the center of the ?eld of view was used for imaging. Experimental Procedures and Operational Workflow:

The loop was placed in the scanner, with the MVAD? pump positioned in the center of the imaging bore. The pump was connected to the controller and started. The speed was increased to 14,000 rpm, providing an estimated ?ow rate of

6：2 L/min. After a 5 min circulation time with no radiopharmaceutical present, the PET scanner acquired a baseline image set over 10 min. The 18F-NaF radiotracer was then injected into the loop. After a 5 min circulation time to achieve a homogeneous mixture, 10 min of imaging was initiated. Data Analysis Methods:

The reconstructed images were analyzed using ASIPro software. Regions of interest in the full ?eld of view were manually drawn over the images, and the mean voxel values of the counts were determined.