Incidental finding of [99mTc]Tc-MIBI uptake in a post-radiotherapy breast without recurrence of cancer.

The oncophilic nature of [99mTc]Tc-MIBI makes this radiopharmaceutical useful in cancer diagnostics, with particular emphasis on breast cancer. Increased uptake of [99mTc]Tc-MIBI in tests performed for non-oncological indications always raises the suspicion of its neoplasmatic character and requires further clinical diagnostics, which is especially justified in patients with a previous history of cancer. However, the presented case illustrates that focally increased uptake of [99mTc]Tc-MIBI is not always associated with the presence of cancer cells and may result from post-therapeutic changes.

Quality and utility of [123I]I-metaiodobenzylguanidine cardiac SPECT imaging in nondiabetic postinfarction heart failure patients qualified for implantable cardioverter defibrillator.

OBJECTIVE: Impaired cardiac adrenergic activity has been demonstrated in heart failure (HF) and in diabetes mellitus (DM). [123I]I-metaiodobenzylguanidine (MIBG) enables assessment of the cardiac adrenergic nervous system. Tomographic imaging of the heart is expected to be superior to planar imaging. This study aimed to determine the quality and utility of MIBG SPECT in the assessment of cardiac innervation in postinfarction HF patients without DM, qualified for implantable cardioverter defibrillator (ICD) in primary prevention of sudden cardiac death. METHODS: Consecutive patients receiving an ICD on the basis of contemporary guidelines were prospectively included. Planar MIBG studies were followed by SPECT. The essential analysis was based on visual assessment of the quality of SPECT images ("high", "low" or "unacceptable"). The variables used in the further analysis were late summed defect score for SPECT images and heart-to-mediastinum rate for planar images. MIBG images were assessed independently by two experienced readers. RESULTS: Fifty postinfarction nondiabetic HF subjects were enrolled. In 13 patients (26%), the assessment of SPECT studies was impossible. In addition, in 13 of 37 patients who underwent semiquantitative SPECT evaluation, the assessment was equivocal. Altogether, in 26/50 patients (52%, 95% confidence interval 38-65%), the quality of SPECT images was unacceptable or low and was limited by low MIBG cardiac uptake and by comparatively high, interfering MIBG uptake in the neighboring structures (primarily, in the lungs). CONCLUSIONS: The utility of MIBG SPECT imaging, at least with conventional imaging protocols, in the qualification of postinfarction HF patients for ICD, is limited. In approximately half of the postinfarction HF patients, SPECT assessment of cardiac innervation can be impossible or equivocal, even without additional damage from diabetic cardiac neuropathy. The criteria predisposing the patient to good-quality MIBG SPECT are: high values of LVEF from the range characterizing the patients qualified to ICD (i.e., close to 35%) and left lung uptake intensity in planar images comparable to or lower than heart uptake.

Chronic Total Occlusion Of Coronary Artery Without Previous History Of Myocardial Infarction: A Role Of Spect.

not required.

Intramyocardial plasmid-encoding human vascular endothelial growth factor A165/basic fibroblast growth factor therapy using percutaneous transcatheter approach in patients with refractory coronary artery disease (VIF-CAD).

BACKGROUND: VIF-CAD randomized, placebo-controlled, double-blind trial was an attempt to induce therapeutic angiogenesis by percutaneous intramyocardial transfer of bicistronic (vascular endothelial growth factor/fibroblast growth factor [VEGF/FGF]) plasmid (pVIF) in patients with refractory heart ischemia. Myocardial perfusion, clinical symptoms, exercise tolerance, left ventricular function, and safety were assessed. METHODS: Fifty-two patients with refractory coronary artery disease were randomized to receive VEGF/FGF plasmid (n = 33) or placebo plasmid (n = 19) into myocardial region showing stress-induced perfusion defects. Repeat stress and rest technetium Tc 99m sestamibi single-photon emission computed tomography at 5 months was the primary efficacy measure. Secondary assessment included Canadian Cardiovascular Society class and exercise tolerance at 5 and 12 months. RESULTS: Rest- and stress-induced perfusion defects did not differ between groups. Canadian Cardiovascular Society functional class improved after 5 (P = .0210) and 12 months (P = .0607) in the treatment group. The exercise tolerance of treated patients improved: total exercise time increased marginally (P = .0541); maximum workload (P = .0419) and total test distance (P = .0473) increased significantly, compared to placebo. CONCLUSION: Bicistronic VEGF/FGF plasmid therapy did not improve myocardial perfusion measured by single-photon emission computed tomography. However, treated patients experienced improvement with respect to exercise tolerance and clinical symptoms. Intramyocardial VEGF/FGF bicistronic plasmid transfer seemed safe throughout the follow-up period of 1 year.

Verification of the left ventricular ejection fraction from gated myocardial perfusion studies (GSPECT).

INTRODUCTION: The perfusion study (which may be obtained using SPECT or GSPECT technology within six hours of administration of the radionuclide Tc-99m-MIBI) reflects the regional blood supply to the left ventricular [LV] myocardium at the time of radionuclide administration (i.e. at rest, at peak exercise, or at peak vasodilatation), while the values of EF, EDV, and ESV measured using GSPECT are parameters of LV contractility at the time of image acquisition (i.e. at rest or in a nearresting state following exercise or vasodilatation). Planar radionuclide ventriculography [RNV] is, however, considered to be the most accurate method for calculating LVEF. AIMS: The main goal of the study was to compare the values of EF obtained by the most frequently used method, GSPECTQGS, and the reference method, RNV - taking into consideration various clinical scenarios (presence or absence of LV dilatation) and various conditions under which GSPECT was recorded (at rest, post-exercise, or post-dipyridamole). METHODS: Two hundred patients (145 males) aged 58+/-11 (18-80) with previously confirmed (n=166, of whom 108 had a history of myocardial infarction) or suspected (n=34) coronary artery disease were included in the study. Ranges of normal values for EF, EDV, and ESV were established based on a group of 26 'normal' subjects. LV dilatation was defined as an EDV >127 ml (at rest, measured by QGS) - this was present in 88 patients. Myocardial perfusion studies were obtained using GSPECT following administration of Tc-99m-MIBI at rest (all patients), as well as one hour after treadmill exercise (138 patients) or dipyridamole administration (48 patients). The resting RNV was conducted within three weeks of the GSPECT exam. The EF values obtained by QGS and RNV were compared for patients with and without LV dilatation. EF, EDV, and ESV values obtained by QGS were compared for resting patients, post-exercise, and post-dipyridamole. RESULTS: 1. The GSPECT EF values calculated using QGS software, at rest or one hour after treadmill exercise or dipyridamole administration, demonstrated, for the study population as a whole, a significant, strong correlation with the results obtained by the reference method, RNV (correlation coefficient, r> or =0.86). The correlation was stronger in patients with LV dilatation than in those without. Both in patients with and without LV dilatation the correlation of EF with RNV was slightly weaker for postexercise (relative to resting) and post-dipyridamole (relative to post-exercise) measurements. 2. QGS tended to underestimate the absolute values of EF, as compared to RNV. 3. In post-exercise and post-dipyridamole measurements, relative to the resting measurements (in patients with previously diagnosed or suspected coronary artery disease) the mean values of EF were lower while EDV and ESV were higher. CONCLUSIONS: In order to complement data on myocardial perfusion, the GSPECT-QGS technique should be optimally used to calculate LV contractility parameters at rest (as opposed to post-exercise or post-dipyridamole), and include a range of normal values for EF, EDV, and ESV, obtained using QGS. Of note, EF measurements by GSPECT are more accurate for dilated than non-dilated ventricles.