Cardiac PET imaging of blood flow, metabolism and function in normal and infarcted rats

The rat heart is an excellent model for the investigation of cardiac physiology and metabolism. It has been used extensively for ex vivo studies of the normal heart as well as for the study of various heart diseases. With the advent of dedicated high-resolution small animal PET scanners, it is now possible to transpose many of the cardiac investigations routinely used in humans to the rat. These include the in vivo measurement of myocardial blood flow, metabolism, and function. Because these techniques are non-invasive, the same animal can be imaged repetitively, thus allowing for follow-up studies of disease progression and for the monitoring of new therapeutic methods. In this work, we report on cardiac studies performed in normal and diseased rats using the Sherbrooke avalanche photodiode PET scanner, a small animal PET imaging device achieving 14 μl volumetric spatial resolution with excellent image signal-to-noise ratio. The system also features flexible list-mode data acquisition, which allows dynamic studies to be resampled as desired for kinetic modeling. Examples of the application of cardiac PET imaging to the follow-up of infarcted rats treated with experimental revascularisation therapy will be presented.