Brain Imaging Before and After Thrombectomy

Imaging before (left) and after (right) the 4.5-minute thrombectomy using the ADAPT technique and the ACE68 catheter

Minutes count for patients who are experiencing a stroke caused by a blood clot blocking the blood supply to a part of their brain. The longer the blood supply is cut off, the worse the damage.

In early June 2016, Jonathan Lena, M.D., a new neuroendovascular surgeon at the MUSC Health Comprehensive Stroke & Cerebrovascular Center, performed a thrombectomy in record time—five minutes instead of the 40 to 45 minutes that is often required—using the new ACE68 catheter (Penumbra) and the ADAPT technique that was pioneered at MUSC Health. The ACE68 device employs the latest technology available to aspirate large clots to restore blood flow to the brain, and perhaps more importantly, the ACE68 design optimizes navigation through the tortuous vessels to enable fast and effective thrombectomy procedures. Lena was the first in the world to perform a thrombectomy using the new ACE68 catheter.

 The ADAPT technique aims to remove a large-vessel clot in its entirety with a large-diameter aspiration catheter. For ADAPT, this large catheter is inserted via the femoral artery and advanced to the site of the clot, where suction is applied to remove the clot and restore blood flow to the brain. If the first-pass attempt is unsuccessful, stent retrievers can then be used.

This technique was developed by MUSC Health neuroendovascular surgeons M. Imran Chaudry, M.D., Alejandro M. Spiotta, M.D., Aquilla S. Turk, D.O., and Raymond D. Turner, M.D., who reported their initial findings in a seminal 2014 article in the Journal of Neurointerventional Surgery (doi: 10.1136/neurintsurg-2013-010713) and longer-term results from a single center (MUSC Health) in an article published online ahead of print on April 18, 2016 (doi: 10.1136/neurintsurg-2015-012211) in the same journal.

In the April 2016 article, the MUSC Health team reported the results of a retrospective analysis, showing  that  blood vessels were successfully reopened in 180 (94.2%) of 191 consecutive patients with acute ischemic stroke who underwent thrombectomy using direct aspiration (ADAPT) at MUSC Health. Direct aspiration alone was used in 145 cases; additional use of stent retrievers was required in another 43 cases. The time to open the blood vessel was 29.6 minutes with ADAPT if aspiration was successful and 61.4 minutes if other devices were required. Good 90-day outcomes were achieved in 57.7% of patients who underwent direct aspiration only and 43.2% of those who required adjunct therapies. Many other institutions have adopted ADAPT and are reporting promising results in their own series of patients.

“The goal in ADAPT is to take the largest-bore catheter available up to the blood clot and put suction where it’s blocked and pull the clot out of the head to reestablish blood flow in that blood vessel,” said Turk. “Obviously, the larger the catheter or tube that you can use, the bigger clot you can suck out and the more effective it can be.”

Up until early June, the biggest catheter available had been the ACE64, a .064-inch inner diameter catheter. The bigger inner diameter of the ACE68 catheter—.068 inch instead of .064—makes it possible to aspirate bigger clots in a single pass, and it has been specially designed to navigate more easily through the blood vessels. The MUSC Health endovascular team has worked closely with Penumbra in the design of the catheter to optimize it for use with the ADAPT technique.

“The new technology of the ACE68 aspiration catheter made the overall experience and procedure a lot quicker, a lot easier, and a lot safer for the patient,” said Lena. “It was a single pass, and that was it, and it went very well.”

Mechanical thrombectomy using stent retrievers is now considered standard of care for patients with large-vessel clots. In 2015, the American Heart Association issued a scientific statement, published in October issue of Stroke, recommending rapid thrombectomy in addition to tissue plasminogen activator or tPA, a clot-busting drug that must be given within the first few hours of a stroke, on the basis of the promising findings of five large clinical trials comparing treatment with tPA alone vs treatment with tPA plus thrombectomy using stent retrievers in large-vessel clots: MR CLEAN, EXTEND-IA,  ESCAPE, SWIFT PRIME, and REVASCAT. Two MUSC Health faculty— Bruce I. Ovbiagele, M.D. MSCR, Chair of the Department of Neurology, and Edward C. Jauch, M.D., Director of the Division of Emergency Medicine—were among the authors of the guideline, issued on behalf of the American Heart Association Stroke Council.

Since the publication of the seminal 2014 article by the MUSC Health team, a number of single-center series studies have reported impressive recanalization times (the time it takes to open the blood vessel) and good neurological outcomes with the ADAPT technique using a large-bore catheter, suggesting that it could offer an alternative approach to stent retrievers for mechanical thrombectomy. To determine whether this alternative approach could become standard of care, clinical trials are needed comparing it to stent retrievers in stroke patients with large-vessel clots. The MUSC Health neuroendovascular surgery team is currently running the COMPASS trial (COMParison of ASpiration vs Stent retriever as first-line approach; Clinicaltrials.gov identifier NCT02466893) in conjunction with colleagues Dr. J. Mocco of Mount Sinai and Dr. Adnan Siddiqui of the University of Buffalo. The trial is randomizing patients to either ADAPT or a stent retriever as the initial thrombectomy technique. The trial, scheduled to enroll 270 patients, has enrolled 90 patients in the past year at ten sites in the United States.

ADAPT Technique

 

a) Neuron Max is placed in the distal cervical internal carotid artery.  The ACE 68 catheter is advanced over the 3 Max catheter telescoped with a Fathom 16 wire to the clot occluding the middle cerebral artery (MCA). 

 

 

 

 

 

b)  The ACE 68 catheter advanced to the face of the clot in the MCA and 3 MAX and wire being removed. 

c)  Clot ingested through the ACE 68 catheter under aspiration.