Acta medica Austriaca. Supplement最新文献

Percutaneous transluminal coronary angioplasty provides the opportunity to study ischemic alterations in the setting of acute transient coronary occlusions in man. In 124 patients changes in hemodynamics, global and regional left ventricular function, collateral flow and mitral valve incompetence, alterations in the concentrations of atrial natriuretic peptide, renin and aldosterone concentrations as well as metabolic changes were studied. In 39 patients with single vessel disease presenting with isolated stenosis in the left anterior descending artery (LAD), but normal global as well as regional left ventricular function hemodynamic and ventriculographic abnormalities were found to be present during intraluminal occlusion for 60 seconds. The mean heart rate increased from 76.3 +/- 15.8 to 80.4 +/- 14.9 beats/min (p less than 0.01) and the mean end diastolic volume index (EDVI) increased from 92.8 +/- 17.1 to 104.6 +/- 17.1 ml/m2 (p less than 0.001). The end systolic volume index (ESVI) also increased from 27.5 +/- 11.3 to 48.2 +/- 12.1 ml/m2 (p less than 0.001). By contrast, mean global left ventricular ejection fraction showed a highly significant reduction from 70.7 +/- 8.8 to 53.8 +/- 7.9% (p less than 0.001). This was paralleled by a reduction in circumferential fibre shortening velocity (VCF) from 1.44 +/- 0.48 to 0.81 +/- 0.31 L/s during LAD occlusion (p less than 0.001). Mean end diastolic left ventricular pressure (EDP) rose significantly from 17.0 +/- 6.8 to 30.1 +/- 9.0 mm Hg (p less than 0.001). In the left ventricular segments supplied by the LAD there was a significant drop in regional shortening. Compensatory increase of regional wall motion in the segments supplied by the right coronary artery (RCA) or circumflex artery (ACX) could not be documented. In the group as a whole the end systolic pressure-volume curves were found to be shifted to the right and the end diastolic pressure-volume curves were elevated, indicating a decrease of contractility and an increase of chamber stiffness. During four consecutive balloon inflations 60 patients showed a significant (p less than 0.001) reduction in peak dp/dtmax and peak dp/dtmin values within the first 30 seconds after coronary artery occlusion and a highly significant (p less than 0.001) increase in left ventricular end diastolic pressures. These changes proved to be reproducible and were found to be almost identical in the four consecutive inflation cycles. The effects of reperfusion were also studied with reperfusion times of 1 min in 15 patients, 3 min in 20 patients and 5 min in 25 patients.4+ balloon inflation.(ABSTRACT TRUNCATED AT 400 WORDS)

Standardization of nuclear medicine renal studies is required in order to permit the comparison of study results of a patient obtained at different laboratories. Furthermore, standardization is a prerequisite for quality control of the analysis part of the procedure. The guidelines presented here are based on a survey carried out amongst nuclear medicine laboratories in Austria and have been edited and harmonized in a workshop organized by the Austrian Nuclear Medicine Society. The guidelines include detailed descriptions of the requirements of instrumentation, of the methods of acquisition, dosage and radiation dose of the commonly used radiopharmaceuticals and all aspects of the analysis of digital renograms. A comprehensive section deals with the determination of renal clearance from the renogram, further sections cover the usage and recommended methods of captopril renography for the diagnosis of unilateral renal artery stenosis and of the frusemide renogram for the diagnosis of nephropathy and uropathy.

The assessment of myocardial viability following interventions aiming at restitution of antegrade blood flow by PTCA and thrombolysis has become one of the most important goals to judge interventional success. Conventional markers as ECG, the extent of the regional wall motion abnormality and enzymes have conceptual limitations. We had shown previously that increased residual glucose metabolism in reperfused myocardium can be assessed by F-18 2-deoxy-glucose (FDG) and positron emission tomography (PET) and will predict functional recovery in reperfused myocardium. The present study introduces a novel concept for the evaluation of myocardial viability by the application of multiple tracer techniques and investigates tracer behaviour in relation to blood flow, regional wall motion, coronary anatomy and histology. The experimental data compare segmental uptake of F-18 FDG with the current most clinically important perfusion marker Tl-201 and Tc-99m (Sn) pyrophosphate (Tc-99mPPi) as a marker of myocardial necrosis in a canine model following a 3 hour intracoronary balloon occlusion and subsequent reperfusion and therefore in a clinically attributable occlusion and reperfusion scenario. Myocardial blood flow was assessed by microspheres, regional fractional tracer retention fractions were evaluated from tissue tracer concentrations, the arterial input function and quantitative blood flow measurements. The extent of ischemic damage was evaluated by TTC post mortem staining, histology, and histochemistry. Additional studies to illucidate the mechanism of increased glucose utilization were done by analysis of other substrates as lactate. The result within the area at risk was assessed in relation to the metabolic behaviour. PET methods were validated in the same dog model as a quantitative biochemical in-vivo assay and imaging procedure and demonstrate the ability of this noninvasive techniques to measure blood flow and myocardial metabolism, especially exogenous glucose utilization. Time dependent and repetitive PET studies may indicate a delayed recovery of myocardial metabolism following an ischemic event with a pattern of a blood flow-metabolism mismatch, characteristic for persistent viability. Metabolic data by imaging correlate with reference techniques as arterio-venous sampling and post mortem histochemical staining method using TTC, PAS, and glycogen techniques. The clinical part applies the proposed tracer concept to patients with acute myocardial infarction and following reperfusion interventions as well using conventional markers and again positron markers. These studies indicate possibilities to assess myocardial viability by the same simultaneou

293 cases of acute hepatitis occurring within two years were analyzed with regard to type of viral infection, clinical course and outcome. Infections occurring in high risk groups as in drug addicts, transfused patients and medical staff were evaluated separately. Within the "posttransfusion group" there was a relatively high incidence of hepatitis B virus infection, high-lighting the need for more extensive screening of blood products for the hepatitis B virus. The prognosis of the disease was independent of time of stay in hospital, of treatment with beta-Cyanidanol and vitamins and of accidental corticosteroid therapy. The highest prevalence of chronicity was found in the Non-A-Non-B group.