Angiojet as a Cause of AKI??

The Angiojet Rheolytic Thrombectomy System is a medical device currently used to re-establish blood flow in a variety of settings. Briefly, a catheter is introduced into an area of thrombosis and a saline stream is directed towards the thrombus of interest. These saline jets generate a localized low pressure zone via the Bernoulli principle, leading to breaking up of the thrombus. The saline and clot particles are then sucked back into the catheter, avoiding potential embolic complications.

Angiojet has been primarily used for removing thrombus from arteries--for example, in acute myocardial infarction or acute graft thrombosis, for instance. It's also been useful in restoring flow in some dialysis accesses. More recently, however, efforts to use Angiojet in the treatment of venous clots--such as DVT or pulmonary emboli--have been attempted.

At a recent Renal Grand Rounds, one of the fellows presented an interesting case of a patient who developed acute renal failure shortly after undergoing attempted Angiojet therapy for a pulmonary embolus. In addition to a rising creatinine and oliguria, the patient developed red, heme-positive urine with only a few red blood cells, and labs reflecting intravascular hemolysis. Although it is not yet rigorously defined as a cause of acute renal failure, others have reported an association between Angiojet and AKI. It is possible that the Angiojet procedure is more likely to result in hemolysis if thrombectomy is attempted in a large, open space (e.g., for treatment of DVT/PE in a larger vein), as there have generally not been such complications when Angiojet has been used in restoring flow to arteries where the area of thrombus is relatively localized.

It will be interesting to see if there are further reports of this type of AKI with Angiojet.  I purposely put TWO questions marks in the title since I fully admit that much more work needs to be done in order to actually prove causality.