title: Mechanical thromboembolectomy for acute ischemic stroke: comparison of the catch thrombectomy device and the Merci Retriever in vivo.
abstract: OBJECTIVE
  The purpose of the study was to compare efficacy and potential complications of 2 commercially available devices for mechanical thromboembolectomy.
  
  
  METHODS
  Devices were tested in an established animal model allowing the use of routine angiography catheters and thrombectomy devices. Radio-opaque thrombi were used for visualization of thrombus-device interaction during angiography. The Merci Retrieval System and the Catch Thromboembolectomy System were assessed each in 10 vessel occlusions. For every occluded vessel up to 5 retrieval attempts were performed.
  
  
  RESULTS
  Sufficient recanalization was achieved with the Merci Retriever in 90% of occlusions, and with the Catch device recanalization was achieved in 70% of occlusions. Recanalization at the first attempt occurred significantly more often with the Merci Retriever compared to the Catch device (OR, 21; 95% CI, 1.78-248.11). Consequently, significantly more attempts (P=0.02) had to be performed with the Catch device; therefore, time to recanalization was longer. Thrombus fragmentations during retrieval were caused more often by the Catch device compared to the Merci Retriever (OR, 15.6; 95% CI, 1.73-140.84), resulting in a higher distal embolization rate. During retrieval both devices lost thrombotic material at the tip of the guide catheter, which was then aspirated in most cases.
  
  
  CONCLUSIONS
  Both distal devices are effective for thromboembolectomy. To avoid loss of thrombotic material and distal embolization, the use of large luminal balloon guide catheters and aspiration during retrieval seems to be mandatory. The design of the Merci Retriever appears to be more efficient during thrombus mobilization and retrieval with less fragmentation compared to the Catch Thromboembolectomy System.
authors.affiliation: Department of Interventional and Diagnostic Neuroradiology, University of Bern, Inselspital, Freiburgstrasse 4, CH-3010 Bern, Switzerland. Caspar.brekenfeld@insel.ch
authors.forename: Caspar
authors.initials: C
authors.lastname: Brekenfeld
authors.forename: Gerhard
authors.initials: G
authors.lastname: Schroth
authors.forename: Marwan
authors.initials: M
authors.lastname: El-Koussy
authors.forename: Krassen
authors.initials: K
authors.lastname: Nedeltchev
authors.forename: Michael
authors.initials: M
authors.lastname: Reinert
authors.forename: Johannes
authors.initials: J
authors.lastname: Slotboom
authors.forename: Jan
authors.initials: J
authors.lastname: Gralla
mesh_terms: D000208:Acute Disease; D000818:Animals; D002545:Brain Ischemia / Q000601:surgery*; D002404:Catheterization; D004195:Disease Models, Animal; D004867:Equipment Design; D020767:Intracranial Thrombosis / Q000601:surgery*; D011183:Postoperative Complications; D020521:Stroke / Q000601:surgery*; D013396:Suction; D013552:Swine; D017131:Thrombectomy / Q000295:instrumentation* / Q000379:methods*