Angioscopic observations after percutaneous thrombectomy of thrombosed hemodialysis grafts

PURPOSE: To use angioscopy to evaluate and compare the amount of residual thrombus and endoluminal wall damage in hemodialysis grafts after percutaneous thrombectomy procedures. MATERIALS AND METHODS: Thirty-nine thrombectomy and angioscopy procedures were performed in 35 patients. Percutaneous thrombectomy methods included eight different mechanical thrombectomy devices and the 'lyse and wait' technique. Videotaped images of 33 angioscopic examinations were independently reviewed by three radiologists. Two parameters - the amount of residual thrombus and degree of endoluminal wall damage - were scored on a scale of 1 to 5. Data were initially analyzed to validate the grading system and then further studied to compare the different thrombectomy techniques. RESULTS: The Spearman rank order analysis validated the data pertaining to the amount of residual thrombus (r = 0.71, P < .0001), but there was poor correlation between reviewers regarding the degree of endoluminal wall damage. Combined scores from three reviewers revealed that the Cragg brush and Percutaneous Thrombectomy Device (PTD) left the smallest amounts of residual thrombus. The other methods tested, listed by increasing amount of residual thrombus, were the Endovac, Hydrolyser, Amplatz Thrombectomy Device, AngioJet, Oasis, and the lyse and wait technique. There were two complications related to angioscopy procedures. CONCLUSION: Subjective observations reveal that wall-contact thrombectomy devices leave less residual thrombus than hydrodynamic devices, aspiration devices, or the lyse and wait technique.