The Fate of Emboli Post-Recanalization of Thrombus-Occluded Artery and Vein in Yorkshire Pigs

Abstract

Aged thrombi (4-day old) could neither be disaggregated by thrombolytic enzymes nor removed by balloon thrombectomy. Metabolic fate of thrombi post-recanalization was determined with 111In labeled platelets. Aged (4-day) labeled platelet-emboli were induced in the femoral, carotid artery and jugular vein in twelve Yorkshire pigs. The thrombi were pulverized with a high speed impeller (80,000 RPM) and the debri generated were flushed with the effluent with heparinized saline and allowed to localize in the down-stream perfusion beds of lungs, liver, legs or brain. The debri generated during recanalization of occluded vessels were also analysed for size distribution by differential filtration (5, 12, 75, 500 and 1000 μm) and radioactivity was determined with a Geiger probe. Autologous platelets were labeled with lllln tropolone (400-500 μCi); 111In labeled platelet-thrombi were induced.by thrombin addition in segments (4-5 cm of ligated vessels in femoral/carotid artery and jugular vein. The residual thrombi were monitored with a Geiger probe and gamma counter. The emboli in the leg-muscle, lungs and brain were imaged with a gamma camera and quantified with an ionization chamber. Filtration indicated the average size of emboli (75 μm). Most of debri from the jugular vein were found in the lungs and liver. Small amount of debri from carotid and femoral artery was found in brain and leg muscle respectively. Labeled platelets provided a simple technique for determination of the fate of emboli generated by recanalization in the pig model.