Abstracts XIX Brazilian Congress of Nuclear Medicine

1. CARDIOLOGY

Variations on left ventricle ejection fraction (LVEF) from rest to exercise may occur and on occasion may be related to some pathologic states, for example, induction of myocardial stunning following exercise. To evaluate if this is a clinically relevant issue for the routine evaluation of patients, we analysed 39 consecutive patients with known coronary artery disease undergoing exercise myocardial perfusion scintigraphy (1 day protocol). Images were acquired in circular orbit of 180 degrees (+ 45 RAO to - 45 LPO), with 3 degrees steps at 45 minutes following injection of 370 MBq of Sestamibi Tc-99m at rest and 1110 MBq at peak exercise. A matrix 64x64, 8 cycles per frame and PHASE MODE protocol (synchronized by the ECG) were parameters used for acquisition. The images were reconstructed, reoriented and processed, obtaining tomographic slices. A computer XPERT system (Elscint, Haifa-Israel), equipped with the Cedars G-SPECT program, was used for processing and for LVEF calculation.The mean LVEF obtained at rest following the rest injection was 54,2%, while the mean LVEF obtained at rest following the exercise injection was 55,1%. These findings support the hypothesis that there is no significant difference between LVEF values following rest or exercise injections for the routine evaluation of patients with coronary artery disease.