REPERFUSION TECHNIQUES

 

1.Stentretriever Assisted Vacuum-locked Extraction (SAVE)

Maximizing First-Pass Complete Reperfusion with SAVE is a paper describing a thrombectomy technique (https://www.ncbi.nlm.nih.gov/pubmed/28194477), which results in high rates of first-pass reperfusion. The proposed approach for clot retrieval combines a distally placed stent-retriever and a proximally placed aspiration catheter which act as a unit, offering a distal (stent-retriever) and proximal capture of the clot (aspiration catheter) while being withdrawn simultaneously under continuous proximal aspiration into the cervical guide catheter. The addition of other techniques/steps (“active push deployment” for better clot caption, “bare wire technique” for maximizing flow inside the aspiration catheter, “grappling hook technique” for time saving) resulted in an excellent overall rate of successful reperfusion (mTICI ≥2b) of 100% and an exceptionally high rate of first-pass complete reperfusion (mTICI 3) of 72%.

More on SAVE soon on a commented online video tutorial.

 

2.Retriever wire supported carotid artery revascularization (ReWiSed CARe) in acute ischemic stroke with underlying tandem occlusion caused by an internal carotid artery dissection: Technical note.

Want to treat a tandem occlusion caused by an ICA dissection in a timely manner and without losing the true-lumen? Try our novel Retriever Wire Supported Carotid Artery Revascularization (ReWiSed CARe) technique (https://www.ncbi.nlm.nih.gov/pubmed/28162027). This technique can also be applied to tandem occlusions caused by carotid stenosis.

 

High-grade stenosis of the left internal carotid artery and intracranial occlusion of the left middle cerebral artery. At first, navigation of a microcatheter distally to the clot and implantation of a stentretriever with a 0.014 inch wire (for example Preset lite, Aperio etc.; the Trevo 4x30mm we are frequently using comes with a 0.018 inch wire). Use the wire of the stentretriever to advance a carotid stent with standard monorail technique, implant the stent, dilate any residual stenosis with a PTA balloon and then advance an aspirationcatheter through the carotid stent to perform intracranial thrombectomy. If you use the SAVE-technique for thrombectomy be sure to retrieve the stentretriever within the tip of the aspirationcatheter, to avoid entanglement of the carotid stent with the stentretriever.

 

3.The need for proximal/extracranial aspiration during clot/stent/aspirationcatheter retrieval

Publications have already described the danger of clot-shearing during immobilization of the clot intracranially. The same danger of clot-shearing applies to the moments of stentretriever/clot/aspirationcatheter unit retraction within the tip of the guide catheter/sheath. This exact case is depicted in Fig 1 during embolectomy of a mid-basilar occlusion (A). B shows recanalization of the occlusion after one maneuver but without proximal aspiration on the guide catheter there is clot-shearing at the catheter tip seen on the early images of the series (C), with dislocation of the clot towards the basilar artery during the angiogram (D and E). Control-angiogram shows re-occlusion of the basilar artery (F) which could be recanalized with another maneuver (G), but resulted in an incomplete reperfusion of the downstream territory. This danger can be reduced by applying aspiration on the guide catheter during retraction of the unit, while preserving vacuum within the aspiration catheter either with pump-aspiration or with the use of a vacuum-lock syringe. In our experience, the addition of proximal aspiration to a primarily combined approach (stentretriever plus aspiration-catheter) results in high rates of mTICI3 reperfusion.

Fig 1