title: Flow-independent dynamics in aneurysms: intra-aneurysm pressure measurements following complete flow cessation in internal carotid artery aneurysms.
abstract: OBJECTIVE
  To determine if complete flow obliteration by covered stents reduces intra-aneurysm pressures in internal carotid artery (ICA) aneurysms.
  
  
  METHODS
  A single lumen microcatheter was placed into the aneurysm sac prior to covered stent deployment in 3 patients and connected to a pressure monitoring system. The intra-aneurysm pressure was continuously monitored, and readings were recorded prior to and immediately after stent deployment and at 5-minute intervals up to 20 minutes after stent placement. Complete occlusion of flow into the aneurysms was confirmed by carotid angiography.
  
  
  RESULTS
  There was no change in mean pressure within the aneurysm before and immediately after stent placement (80 mmHg) in any patient, nor was there a change in waveform of the intra-aneurysm pressure recording. The average of intra-aneurysm pressures among the 3 patients was higher (99 mmHg) at 10 and 15 minutes after stent placement. In 2 patients, the microcatheter was retracted into the parent arterial lumen; no difference in pressure was noted.
  
  
  CONCLUSIONS
  Our observations suggest no change in the pressures within the aneurysm after complete flow cessation (flow-independent). These findings may assist clinicians in better understanding aneurysm hemodynamics and rupture after covered stent deployment.
authors.affiliation: Zeenat Qureshi Stroke Institute, and Department of Cerebrovascular Diseases, CentraCare Health, St. Cloud, Minnesota, USA.
authors.forename: Adnan I
authors.initials: AI
authors.lastname: Qureshi
authors.forename: Mushtaq H
authors.initials: MH
authors.lastname: Qureshi
authors.forename: Tanya
authors.initials: T
authors.lastname: Mohindroo
authors.forename: Asif A
authors.initials: AA
authors.lastname: Khan
authors.forename: Kayla
authors.initials: K
authors.lastname: Dingmann
authors.forename: Gregory T
authors.initials: GT
authors.lastname: Sherr
authors.forename: M Fareed K
authors.initials: MF
authors.lastname: Suri
mesh_terms: D000328:Adult; D000783:Aneurysm / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D017542:Aneurysm, Ruptured / Q000209:etiology / Q000503:physiopathology; D001783:Blood Flow Velocity; D002340:Carotid Artery Diseases / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002406:Catheterization, Peripheral / Q000295:instrumentation; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation; D004867:Equipment Design; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008904:Miniaturization; D011237:Predictive Value of Tests; D011312:Pressure; D011859:Radiography; D012039:Regional Blood Flow; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome; D062666:Vascular Access Devices
keywords: aneurysm; aneurysm rupture; aneurysm wall; compliance; covered stent; hemodynamics; internal carotid artery; intra-aneurysm pressure; intrasac pressure; pressure transmission; stent-graft