Pulmonary emboli from pulse-spray and mechanical thrombolysis: Evaluation with an animal dialysis-graft model

PURPOSE: To compare pulmonary emboli resulting from pulse-spray pharmacomechanical thrombolysis (PSPMT) and mechanical thrombolysis performed to declot dialysis-access grafts. MATERIALS AND METHODS: Polytetrafluoroethylene arteriovenous shunts were created in eight dogs and were deliberately clotted at monthly intervals. Animals were randomly assigned to treatment with pulse-spray urokinase thrombolysis or a low-speed rotational percutaneous thrombolytic device. Perfusion imaging, pulmonary-artery pressure measurements, and pulmonary arteriography were performed before and after each procedure. RESULTS: A total of 22 procedures were performed (11 PSPMT and 11 mechanical thrombolysis). Declotting was successful in all procedures, with 100% 30-day patency. Segmental defects were seen on perfusion images after 10 (91%) of 11 PSPMT procedures and two (18%) of 11 mechanical thrombolysis procedures (P <.002). Transient increases in pulmonary-artery pressure occurred in the PSPMT group. Complete resolution of emboli and return to baseline pressures were seen in all cases, even after multiple (up to four) procedures in the same animal. There was no histologic evidence of pulmonary infarction in either group. CONCLUSION: The percutaneous thrombolytic device is effective for declotting dialysis grafts in dogs and results in statistically significantly fewer pulmonary emboli compared with PSPMT.