Myocardial single-photon emission computed tomographic imaging with technetium 99m tetrofosmin: stress-rest imaging with same-day and separate-day rest imaging.

BACKGROUND: Technetium 99m tetrofosmin is a new ethylene diphosphine ligand for myocardial perfusion imaging and has unique properties. We have compared stress-rest single-photon emission computed tomographic (SPECT) imaging with 99mTc tetrofosmin with same-day and separate-day rest imaging to detect myocardial perfusion defects. METHODS AND RESULTS: Myocardial SPECT imaging was performed in 22 patients with coronary artery disease who had undergone planar thallium 201 imaging and coronary angiography. Single-day (stress-rest) and separate-day rest 99mTc tetrofosmin SPECT protocols were compared in the same patient. Images were assessed by a blinded panel to identify myocardial infarction, ischemia, or normal scans. Overall sensitivity for identification of patients with coronary artery disease was 86% (19/22) by both same-day stress-rest and separate-day rest protocols with 99mTc tetrofosmin (p = NS). Of a total of 396 segments studied, 107 abnormal segments were identified at exercise and 76 and 81 at the same-day and separate-day rest tests, respectively (p = NS). Same-day stress-rest and separate-day rest 99mTc tetrofosmin SPECT protocols were also useful for detecting individual coronary stenosis with a greater than 50% lesion: 80% of the left anterior descending, 93% of the right coronary, and 75% of the left circumflex coronary arteries were detected. CONCLUSION: Excellent images were obtained with 99mTc tetrofosmin during both stress and rest. 99mTc tetrofosmin imaging with the same-day stress-rest and separate-day rest imaging protocols have similar diagnostic sensitivities for detection of coronary heart disease.

Myocyte cell damage after administration of doxorubicin or mitoxantrone in breast cancer patients assessed by indium 111 antimyosin monoclonal antibody studies.

PURPOSE: To compare myocyte cell damage induced by doxorubicin or mitoxantrone, we performed left ventricular ejection fraction (LVEF) measurements and indium 111 antimyosin antibody studies in a group of patients with advanced breast cancer who had been treated with these anthracycline derivatives. PATIENTS AND METHODS: We studied 35 patients eligible to receive chemotherapy including the anthracyclines: doxorubicin or mitoxantrone (cumulative dose of doxorubicin, 500 mg/m2; or mitoxantrone, 120 mg/m2). LVEF was measured before and after 10 cycles of chemotherapy. Antimyosin uptake in the myocardium was quantified by means of a heart-to-lung ratio (HLR). RESULTS: Patients treated with doxorubicin presented with a significant decrease in LVEF after chemotherapy (before, 60.4% +/- 8.92%; after, 49.8% +/- 9.71%; P = .001). Antimyosin uptake was observed in all patients with a HLR of 2.03 +/- 0.25. Seven of eight patients with a HLR greater than 2.03 had a greater than 10% decrease in LVEF. Patients treated with mitoxantrone did not present with a decrease in LVEF after chemotherapy (before, 55.4% +/- 6.25%; after, 55.8% +/- 7.25%; not significant). Antimyosin uptake was observed in 14 of 17 patients with a HLR of 1.77 +/- 0.18 (P < .05). CONCLUSION: 111In antimyosin monoclonal antibodies defect myocardial cell damage produced by doxorubicin and mitoxantrone. In patients with advanced breast cancer, cumulative doses of 120 mg/m2 of mitoxantrone produce less myocardial cell damage than cumulative doses of 500 mg/m2 of doxorubicin. 111In antimyosin uptake without decrease in LVEF after treatment with mitoxantrone indicates the presence of myocyte cell damage, but not to the extent necessary to deteriorate function. These results indicate that 111In antimyosin antibody studies are useful in the noninvasive comparative assessment of cardiotoxicity produced by different anthracycline derivatives.

Preexisting human anti-murine antibodies and the effect of immune complexes on the outcome of immunoscintigraphy.

Radiolabeled monoclonal antibodies (MoAb) are useful in radionuclide imaging. Human anti-murine antibodies (HAMA), however, could produce immunologic effects or alter the outcome of immunoscintigraphy. Three patients are reported who had been exposed previously to radiolabeled MoAbs and in whom subsequent immunoscintigraphy was performed. All patients showed abnormal biodistribution of the antibody and increased hepatic uptake. Human anti-murine antibody was demonstrated in all patients. These results indicate that immune complexes are formed after HAMA-MoAb reaction and are then phagocytosed by cells of the reticuloendothelial system.

[Biventricular functional adaptation during a prolonged race. An analysis of global and regional ventricular function]. / Adaptación funcional biventricular durante una carrera de larga duración. Análisis de la función ventricular global y regional.

To determine the effects of a six-hour competitive race on left and right ventricular performance, 99mTc gated blood pool scans were performed to 6 long distance runners before the race (rest), each hour during the race and one hour after concluding the exercise (recovery). Heart rate increased during the race, peaking at 4th hour of competition (55 +/- 3 to 110 +/- 9 lpm; p = 0.001). Evolution of right ventricular ejection fraction showed a similar behavior with the evolution of left ventricular ejection fraction during the competition (r = 0.39; p = 0.006). Blood volume in the lungs increased at the end of the race (index 1.13 +/- 0.14) normalizing at recovery (index 1.03 +/- 0.03). Left and right ventricular peak filling rate had an inverse correlation with pulmonary blood volume (r = -0.31; p = 0.041 and r = -0.47; p = 0.001 respectively). Both left and right ventricular ejection fraction had an inverse correlation with pulmonary blood volume (r = -0.38; p = 0.006 and r = -0.34; p = 0.01 respectively). The anteroseptal regional ejection fraction showed an inverse correlation with end-systolic and end-diastolic volume (r = -0.32; p = 0.03 and r = -0.4; p less than 0.01 respectively). The posterolateral region showed a parallel evolution with the global ejection fraction for both left and right ventricles (r = 0.57; p less than 0.0001 and r = 0.38; p = 0.009 respectively). In conclusion, a transient biventricular functional adaptation during a prolonged race is related to pulmonary blood volume redistribution and to a higher preload for both ventricles and a greater afterload for the right ventricle. The posterolateral and inferoapical regions show a similar behavior as both left and right ventricular ejection fraction, response that does not occur with the anteroseptal regional ejection fraction.

Technetium-99m human polyclonal immunoglobulin G studies and conventional bone scans to detect active joint inflammation in chronic rheumatoid arthritis.

Rheumatoid arthritis is a chronic polyarthritis in which active inflamed joints coexist with joints in remission. We performed bone scans (99mTc-DPD) and 99mTc human polyclonal immunoglobulin G scans (99mTc-IgG) in 18 patients with rheumatoid arthritis to assess the uptake in actively inflamed joints and in joints in which remission after inflammation had occurred. A quantitative analysis of tracer uptake in each joint was performed on both scans. In 123 joints without current active inflammation, an increased 99mTc-DPD uptake was observed (2.31 +/- 1.27), whereas no 99mTc-IgG uptake was noted (1.18 +/- 0.32). Some 78 joints with mild pain or swelling exhibited increased 99mTc-DPD uptake (2.48 +/- 1.14) and increased 99mTc-IgG uptake (1.76 +/- 0.50; P less than 0.001), while 21 joints with moderate to severe pain or swelling exhibited increased 99mTc-DPD uptake (2.39 +/- 0.93) and increased 99mTc-IgG uptake (1.79 +/- 0.51; P less than 0.001). In conclusion, 99mTc-IgG scans distinguish between joints with and without active inflammation in chronic rheumatoid arthritis, whereas bone scans do not. Thus, 99mTc-IgG scans may be useful in identifying joints with current active inflammation in rheumatoid arthritis.

[Circumferential profiles versus visual analysis in studies of myocardial perfusion during exertion using thallium-201]. / Perfiles circunferenciales versus análisis visual en los estudios de perfusión miocárdica de esfuerzo con talio-201.

Two methods of analysis for perfusion myocardial studies with thallium are compared: the conventional visual analysis, and a quantitative method which shows results as circumferential profiles. Three hundred and ninety myocardial segments in 65 patients were studied. Visual analysis showed abnormalities in 44/65 (68%) patients, the quantitative method did it in 53/65 (81%). When localization and/or extension discrepancy between the two methods was found, angiography was always concordant with circumferential profiles findings. Total agreement between the two methods was present in 20/65 (31%) patients. The quantitative method is more sensitive than the visual analysis. It is also more precise in defining localization and extension of thallium defects.