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BACKGROUND: Left ventricular ejection fraction (LVEF) is a valuable measure to assess left ventricular systolic function. Lipid lowering therapy by statins has been shown to have an impact on LVEF already after a 6 months treatment. Higher doses of statins have been claimed to be more effective as compared to a conventional one and even a difference between lipophilic and hydrophilic compounds has been reported. The effect of regular lipoprotein-apheresis (LP-apheresis) on LVEF was previously poorly examined. Patients involved in a regular LP-apheresis program are supposed to undergo a number of follow-up investigations among them myocardial scintigraphy and LVEF, measured by radionuclide ventriculography. METHODS: We examined 18 patients before initiation and after one year of ongoing LP-apheresis. 13 patients (11 males, 2 females, mean age 58.3 ±â€¯5.3 years, groups A) were since more than a year on stable, unchanged statin treatment (atorvastatin 40 mg, simvastatin 40 mg, rosuvastatin 20 mg±ezetimibe), the other 5 patients (3 males, 2 females, mean age 57.1 ±â€¯4.6 years, group B) were intolerant to statins being on micronized fenofibrate±resorption inhibitors (cholestyramine). All patients had a Lp(a) < 30 mg/dl. As part of the usual follow-up monitoring, LVEF was determined by means of radionuclide ventriculography after application of 550 MBq 99m Tc-pertechnetate. RESULTS: The follow-up LVEF was checked at a mean of 48.7 weeks in group A and 51.2 weeks in group B. Except in 1 patient (LVEF 46.8% before vs. 45.2% after LP-apheresis initiation) in group A we noted a significant increase in LVEF in 12 patients of group A (92%) and in all patients of group B. Mean LVEF increased significantly in both groups (A: 42.7±8.1 → 46.5±7.5% (p < 0.001) and B: 41.9±8.4 → 46.5±6.3 %; p < 0.001). The relative rise was nearly identical (group A 9.6%, in group B 9.7%). CONCLUSIONS: Our findings indicate that regular long-term LP-apheresis treatment apparently increases LVEF, independently on current statin treatment. This implies a role of lowering of atherogenic lipoproteins as underlying mechanism. A prospective study should clarify the relative extent of LVEF improvement induced by LP-apheresis.

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There is a strong need for non-invasive detection of human atherosclerotic lesions. One of the radioisotopic approaches using Indium-111-HIG has been shown to accumulate in oxidized LDL-rich foam cells and inflammatory vascular lesions. Earlier human studies in 200 patients, 100 with peripheral vascular disease and 100 with carotid artery disease comparing In-111-HIG scintigraphy with sonographic data revealed a high sensitivity (70%-77%) but a very low specificity (33%-41%). At this time we concluded the approach "not promising" for human studies. However, clinical follow-up over 5 years now shows that those patients with positive In-111-HIG scintigraphy exhibited a significantly higher vascular morbidity (P<0,01) and mortality (P<0,01), especially in the immediate follow-up period. Retrospective analysis discovered higher CRP and isoprostane (8-epi-prostaglandin (PG) F2α) levels in HIG-positive patients at the time of scintigraphy. These findings indicate that In-111-HIG reflecting vascular lesions with a high inflammatory component, probably more prone to rupture, may identify a population at high vascular risk rather than a lesion at risk. The clinical impact of this finding should be assessed in prospective studies.

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After the introduction for penile cancer, the sentinel lymph node imaging is increasingly applied in various types of cancer. After the initial learning phase, 105 patients with vulvar and 24 with cervical cancer have been investigated. In vulvar cancer all the imaged sentinel nodes were discovered by the portable probe intraoperatively. No false negative sentinel node was observed. The most critical issue is the tracer application. Performed strictly intradermally, the sentinel node shows up immediately. Concomitant use of isosulfan blue dye did not improve the results and was stopped therefore. Similarly, more superficial (intra/subendothelial) application brings up better results as compared to deeper injection in cervical cancer patients. No false negative results were seen. Apparently, an almost 100%detection is possible. Our findings clearly show that tracer application is the key for successful imaging. If not done properly, sentinel node may appear later or may even more likely be missed.

Após a introdução para câncer do pênis, a imagem do linfonodo sentinela é cada vez mais aplicada nos diversos tipos de câncer. Após a fase inicial de aprendizagem, 105 pacientes com câncer vulvar e 24 com câncer cervical foram investigados. No câncer vulvar todas as imagens de nodos sentinela foram descobertas por sonda portátil durante o exame. Nenhum nodo sentinela falso negativo foi observado. A questão mais crítica é a aplicação do traçador. Realizada pela via intradérmica, o nodo sentinela surge imediatamente. O corante isosulfan blue não melhora os resultados e seu uso concomitante foi abandonado. Do mesmo modo, a aplicação mais superficial (intra/subendotelial) apresenta melhores resultados quando comparada com a administração mais profunda em pacientes com câncer cervical. Não foram observados resultados falsos negativos. Aparentemente, uma detecção de aproximadamente 100% é possível. Nossos achados mostram claramente que a administração do traçador é um ponto chave para uma imagem com qualidade. Se não for feita corretamente, o nodo sentinela pode aparecer tardiamente ou pode até ser perdido.

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Imaging of tumors with cationic tracers, especially with technetium-99 methoxy isobutyl isonitrile ((99m)Tc-MIBI), revealed high specificity for the diagnosis and follow up of various malignancies. However, these radiopharmaceuticals are of limited value for the diagnosis of malignancies of the abdominal region due to the immediate biliary secretion of the tracer and the associated high background activity. In a prospective, single-blinded protocol, patients with endoscopically diagnosed gastrointestinal malignancies were assigned to undergo (99m)Tc-MIBI imaging of the abdomen. To overcome biliary secretion of cationic tracer we administered 0.04 mg/kg morphine hydrochloride intravenously before the administration of 600 MBq (99m)Tc-MIBI. Planar images were performed in the anterior and posterior views with a double-headed gamma camera and with 3 min acquisition time, followed by single photon emission tomography images (3 degrees, 20 sec/frame). Results were compared to findings of endoscopy, computed tomography scan and surgery. Twenty four patients 17 male and 7 female , mean age 69 years, range 52-83, years were enrolled. All patients suffered from adenocarcinoma, (19 from colorectum, 3 from gastric, 1 from pancreatic and one patient had both gastric and colorectal adenocarcinoma, for a total of 25 tumor lesions). The primary objective- inhibition of biliary secretion- was achieved in 23 of the 24 patients. (99m)Tc-MIBI-imaging was accumulated intra-abdominally in 19 patients. In 2 patients the tumor was endoscopically completely removed before the scan. In these two patients (99m)Tc-MIBI imaging showed no intra-abdominal tracer accumulation. When compared to the endoscopic findings, (99m)Tc-MIBI imaging showed time positive results in 13 of the 23 remaining individual tumor lesions, false positive in 6 and false negative in 4. This study showed a sensitivity of 57% and a specificity of 20% of the above technique for the identification of intra-abnominal adenocarcinomas. Correct diagnosis did not correlate with tumor size. In conclusion, prescintigraphic morphine administration inhibits background activity coming from biliary secretion, and enables better intra-abdominal (99m)Tc-MIBI imaging but with limited sensitivity and poor specificity.

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After various earlier attempts with different radiotracers 51chromium and finally ^IndiumoKIne became the tracers of choice for the radiolabeling of human platelets and the subsequent monitoring of in vivo kinetics. Data on clinical application of platelet survival in atherosclerotic vascular disease and a variety of risk factors are presented. Furthermore, a new approach to use nonradioactive material (rubidium) as label for platelets allowing application in children and pregnants, where only the information on platelet survival is necessary, are discussed. The application of 111lndium-oxine and cold rubidium is an underused reiiable methodology for the assessment of lifespan of human platelets for clinical diagnosis and treatment monitoring.