RT Journal Article
SR Electronic
T1 Initial Infarct Size Predicts Subsequent Cardiac Remodeling in the Rat Infarct Model: An In Vivo Serial Pinhole Gated SPECT Study
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 337
OP 344
VO 47
IS 2
A1 Fatiha Maskali
A1 Philippe R. Franken
A1 Sylvain Poussier
A1 Nguyen Tran
A1 Chris Vanhove
A1 Henri Boutley
A1 Hervé Le Gall
A1 Gilles Karcher
A1 Faïez Zannad
A1 Patrick Lacolley
A1 Pierre Y. Marie
YR 2006
UL http://jnm.snmjournals.org/content/47/2/337.abstract
AB The rat infarct model is widely used to study left ventricular (LV) remodeling, a main cause of heart failure characterized by progressive LV dilatation. Using pinhole collimators and advances in data processing, gated SPECT was recently adapted to image the rat heart. The aim of this study was to assess this new imaging technique for predicting and quantifying variable LV remodeling from the rat infarct model. Methods: Pinhole 99mTc-sestamibi gated SPECT was validated for determining LV volume and identifying the necrotic and nonviable LV segments (<50% of 99mTc-sestamibi uptake) in rats, and it was applied to monitor rat LV function from 48 h to 12 wk after occlusion of the left anterior descending coronary artery (LAD) (n = 20) or sham operation (n = 9). Results: In LAD-occluded rats, 48-h SPECT necrosis was large (≥30% LV) in 6, limited (<30% LV) in 6, and undetectable in 8. End-diastolic volume of LAD-occluded rats was equivalent to that of sham-operated rats at 48 h (320 ± 84 μL vs. 293 ± 48 μL; not significant) but became higher at 12 wk (501 ± 191 μL vs. 343 ± 46 μL; P = 0.01). The follow-up increase in end-diastolic volume, which reflects the remodeling process, was closely related to the initial extent of necrosis revealed by the SPECT images (P < 0.001; R2 = 0.85). This increase was limited in sham-operated rats (50 ± 15 μL) and in the LAD-occluded rats with undetectable necrosis (55 ± 35 μL) but it was around 3- and 7-fold higher in the LAD-occluded rats with limited (165 ± 57 μL) and large (366 ± 113 μL) necrosis, respectively. Conclusion: The variable LV remodeling documented after coronary occlusion in rats closely relates to the variable extent of necrosis provided by this model. Pinhole gated SPECT allows this remodeling to be predicted and quantified and, hence, constitutes an original tool for the experiments scheduled on the rat infarct model.