Increased platelet deposition on polytetrafluoroethylene grafts after balloon catheter thrombectomy

Novel use of the ClariVein® catheter for pharmacomechanical thrombolysis of thrombosed hemodialysis grafts: a case series

INTRODUCTION

The aim of this prospectively collected case series is to demonstrate a novel technique of using the ClariVein® catheter for pharmacomechanical thrombolysis of thrombosed hemodialysis grafts.

METHODS

The analysis comprised 11 procedures in 9 patients from 1 July to 31 December 2016 in which the ClariVein catheter was used in combination with urokinase. Demographic data, procedural data, technical and clinical success rates, and complications were evaluated. The primary and secondary patency rates at 1 and 3 months were also analyzed.

RESULTS

In the 11 procedures performed, the technical and clinical success was 100%. The mean procedural time was 66.8 minutes (range 50-90 minutes), and the mean amount of urokinase administered was 87,000 units. The primary unassisted patency rates at 1 and 3 months were 81.8% and 63.6%, respectively. The secondary patency rates at 1 and 3 months were 90.9% and 81.8%, respectively. Perforation occurred after balloon angioplasty in 1 (9.1%) of the 11 procedures, for which covered stenting was performed. No major complications occurred.

CONCLUSIONS

The combination use of the ClariVein catheter with urokinase for pharmacomechanical thrombolysis in thrombosed hemodialysis grafts is a feasible and safe method that can be performed in a relatively short duration. Our early results have shown 100% technical and clinical success. This case series serves as a platform for an upcoming prospective study to further evaluate this method.

Manual thromboaspiration and dilation of thrombosed dialysis access: mid-term results of a simple concept

PURPOSE

To report the feasibility, safety, and effectiveness of manual thromboaspiration as a single means of declotting dialysis access.

MATERIALS AND METHODS

Between April 1994 and December 1996, 59 consecutive conduits (43 polytetrafluoroethylene [PTFE] grafts, 16 native fistulas) were declotted with 8-F or 7-F angulated catheters. Unmasked stenoses were dilated. Clinical and paraclinical nephrologic surveillance (poor flow, palpation, difficulties with cannulation, increased compression times, increasing venous pressures) led to redilations and stent placements. Rethromboses were treated with further declotting by aspiration. The results are presented according to the life-table method.

RESULTS

The initial success of 43 of 43 PTFE grafts (mean procedure time, 119 min +/- 29 [standard deviation]) led to a primary patency rate of 85% +/- 5% (SE) at 1 month, 33% +/- 8% at 6 months, and 24% +/- 12% at 1 year. A graft was ligated 6 days after declotting for acute bleeding in one patient given high-dose warfarin. The secondary patency rates were 86% +/- 7% at 6 months and 86% +/- 9% at 1 year, with a mean duration of patency of 5.7 months between two radiologic interventions performed to maintain or to restore patency, and 19 stents were placed at a mean follow-up of 3 months. The success rate was 81% for native fistulas, with primary patency rates of 81% +/- 10% at 1 month, 74% +/- 14% at 6 months, and 60% +/- 27% at 1 year; secondary patency rates of 81% +/- 12% at 6 months and 81% +/- 18% at 1 year.

CONCLUSION

Thromboaspiration is a safe and effective method for declotting dialysis access, yielding a low rethrombosis rate during the first month. Overall radiologic management with reintervention on average every 6 months results in high secondary patency rates at 1 year (81%-86%).

Directional atherectomy in the treatment of anastomotic neointimal hyperplasia associated with prosthetic arterial grafts: technique and preliminary results

The development of anastomotic neointimal hyperplasia is a common cause of late prosthetic arterial bypass graft failure. The cost and morbidity of graft failure are high, hence the widespread use of graft surveillance programmes in order to detect graft-related stenoses before they progress to occlusion. However, the optimal treatment of stenoses secondary to neointimal hyperplasia is not clear, with a number of authors reporting poor results with both balloon angioplasty and surgical revision. We report our early experience with the Simpson atherectomy catheter in the treatment of anastomotic neointimal hyperplasia associated with prosthetic arterial grafts at eight sites in seven patients. A high technical success rate may be expected and further long-term studies of this mode of treatment are indicated.

New "mesh basket" for percutaneous removal of wall-adherent thrombi in dialysis shunts

A new basket, developed for percutaneous removal of wall-adherent thrombi, was tested in model thrombosed hemodialysis shunts and clinically in two polytetrafluoroethylene grafts and one Brescia-Cimino shunt after recanalization by aspiration thrombectomy. The residual wall-adherent thrombus was removed by one or two passes with the mesh basket. The occlusion material was firmly captured within the mesh and was removed through an 8F sheath without hardly any material being sheared off from the basket. The device adapts well even to tortuous vessel segments and exerts a gentle brush effect. It may prove to be a valuable adjunct to aspiration thrombectomy or to balloon catheter embolectomy.