chiniofon and Coronary-Disease

Intracardiac thrombi can be localized and quantified by Indium-111-labelling of thrombocytes with a high sensitivity and specificity. The scintigraphic procedure has a complementary evidence to echocardiography. Scintigraphy shows activity and age of thrombosis, whereas echocardiography seems to be superior in determination of mass and localization. In older thrombi scintigraphy fails because of organisation and endothelialization of the thrombus surface. For the reason of determination of the age of an intraventricular thrombus this method might have an increasing acceptance.

Topics: Aged; Blood Platelets; Coronary Disease; Coronary Thrombosis; Heart Ventricles; Humans; Hydroxyquinolines; Indium Radioisotopes; Male; Myocardial Infarction; Organometallic Compounds; Oxyquinoline; Radionuclide Imaging; Recurrence

A 54-year-old man was admitted to hospital with a 3-month history of progressive dyspnea with coughing. A giant right atrial mass, originating from a hepatocellular carcinoma, was visualized by computed tomography, and digital subtraction angiography. The volume of the right atrial mass was increasing rapidly. It was therefore essential to determine whether this giant mass was a tumor thrombus or a multiplication of the hepatocellular carcinoma. 111In-oxine labeled platelet scintigraphy revealed active accumulation in the right atrium caused by the presence of active platelet deposition, and slight accumulation in the lung fields probably due to embolic showers originating from the tumor thrombus in the right atrium. This is the first case report showing that 111In-oxine labeled platelet scintigraphy can aid in confirming the nature of a giant tumor thrombus in the right atrium and can clarify the pathogenesis of the respiratory symptoms.

Topics: Blood Platelets; Carcinoma, Hepatocellular; Coronary Disease; Heart Atria; Heart Neoplasms; Humans; Hydroxyquinolines; Indium; Liver Neoplasms; Male; Middle Aged; Organometallic Compounds; Oxyquinoline; Radionuclide Imaging

Using 111indium oxine and 111indium oxine sulphate as platelet labels, maximal labelling efficiency can be achieved already after 3 minutes at an incubation temperature of 37 degrees C. Mean labelling efficiency values of about 90% are reached at a platelet count of greater than 10(9) platelets/ml, but the labelling efficiency is satisfactory also at a rather low platelet count of about 10(6) platelets/ml (71% on average). Platelet labelling with these tracers allows the calculation of platelet half-life in vivo, and gamma-camera imaging of platelet aggregates in thrombosis and renal transplant rejection as well. In the present study, the platelet half-life is significantly shortened in patients with coronary heart disease (n = 15), peripheral vascular disease (n = 13) and primary hyperlipoproteinaemia (n = 32) in comparison with 106 controls. No age dependence of platelet half-life was found in the different groups of patients whereas in the control group, a significant negative correlation between age and platelet half-life was observed.

Topics: Adult; Age Factors; Aged; Arteriosclerosis; Blood Platelets; Coronary Disease; Half-Life; Humans; Hydroxyquinolines; Hyperlipoproteinemias; Indium; Isotope Labeling; Methods; Microscopy, Electron, Scanning; Middle Aged; Organometallic Compounds; Oxyquinoline; Radionuclide Imaging

High activity labeled platelets could be useful for the detection and observation of small foci of thrombosis by gamma-camera imaging. Therefore platelets were labeled with 111In-oxine containing increasing activities of 111In to determine the elimiting amount of this tracer that did not cause cell damage. A labeling procedure was employed so that all the chemical parameters remained constant except the amount of 111In. Platelet damage was studied by ADP-induced aggregability according to the Born procedure and by scanning and ultrastructural electron microscopy. Platelets labeled with the lowest activity 2.2 MBq/ml of platelet suspension (10(9) cells/ml) showed no alterations. With the highest activity studied, (22 MBq/ml) aggregability decreased by two-thirds and great changes in the shape of the platelets were seen by electron microscopy. These modifications were attributed to the decay of 111In predominantly located in the platelet cytosol. Labeling of platelets with an activity higher than 7.4 MBq/ml is unsuitable for detection of thrombosis since normal platelet functions are not retained.

Topics: Blood Platelets; Coronary Disease; Humans; Hydroxyquinolines; Indium; Organometallic Compounds; Oxyquinoline; Platelet Aggregation; Radionuclide Imaging