Cardiorenal scintigraphy
From NuclearWiki
Review
Hypothesis: 99m-Tc tetrofosmin renal imaging performed in conjunction with gated SPECT myocardial perfusion imaging is both feasible and accurate compared to Tc-99m DTPA renal scanning.
Background: Cardiac function is closely related to renal function. Decreased function of one system often leads to decreased functioning in the other. The assessment of renal and cardiac function during a single study is thus appealing from a clinical standpoint. In addition, since both would be assessed after a single injection of the radioisotope, there would be a significant socioeconomic value.
Objectives: the objective of this study was to see if 99m-Tc tetrofosmin renal scintigraphy could be performed accurately (compared to Tc-99m DTPA renal scintigraphy) when don in conjunction with gated SPECT myocardial perfusion imaging. The study also looked at renal function after adenosine stress as compared to rest renal function.
Research Design: concurrent cohort.
Participants: There were 30 patients in the study. They were all referred for clinical reasons to nuclear myocardial perfusion scanning. Of the 30 patients, 80% had hypertension, 23% had diabetes, and 20% had dilated cardiomyopathy.
Methods: Patients underwent gated SPECT stress-rest myocardial perfusion imaging in standard fashion. The protocol used was a two-day, single isotope (99m-Tc tetrofosmin) procedure. Approximately one week later, most of the patients (24 out of 30) had a standard dynamic renal scan using Tc-99m DTPA.
The rest acquisition started out with planar dynamic and function renal imaging for 30 minutes. Then, gated SPECT myocardial perfusion images were obtained. Patient dosage of the Tc99m was about 10 mCi (370 MBq).
On stress imaging, dynamic renal images were started at the third minute of adenosine infusion. Then, immediately after the renal images were completed, gated SPECT myocardial perfusion imaging was performed. The gated SPECT study used 16 frames per cardiac cycle.
Dynamic renal scanning consisted of a first-pass phase dynamic phase followed by a functional phase, with a total scan duration of 30 minutes. The differential split function was determined as well as time to peak activity and the radiotracer's uptake index.
Results: There was a higher renal uptake index on the Tc99m tetrofosmin study compared to the 99m-Tc DTPA study. This made the images of higher quality visually when using tetrofosmin. Variables for renal function were comparable for Tc-99m tetrofosmin versus Tc-99m DTPA.
Patients undergoing adenosine stress renal imaging overall had a statistically significant (p less than 0.005) drop in their Tc-99m tetrofosmin uptake index as compared to the uptake index which was obtained by at rest.
Conclusion: renal function can be accurately assessed when done in conjunction with 99m-Tc tetrofosmin gated SPECT myocardial perfusion scintigraphy and only requires a single injection of the isotope.
Source: J Nucl Med. 2009 Jul 17. [Epub ahead of print]. Single-Shot Cardiorenal Scintigraphy with 99mTc-Tetrofosmin: A Dynamic Characterization at Rest and During Adenosine Infusion. Fommei E, Bruselli L, Ripoli A, Gimelli A, Ghione S, Giorgetti A, Kush A, Tagliavia ID, Passino C, Marzullo P. "Gabriele Monasterio" Foundation, CNR Institute of Clinical Physiology, Pisa, Italy; Department of Internal Medicine, University of Pisa, Pisa, Italy. Abstract.
