title: Safety of embolic protection device-assisted and unprotected intravascular ultrasound in evaluating carotid artery atherosclerotic lesions.
abstract: BACKGROUND
  Significant atherosclerotic stenosis of internal carotid artery (ICA) origin is common (5-10% at ≥ 60 years). Intravascular ultrasound (IVUS) enables high-resolution (120 µm) plaque imaging, and IVUS-elucidated features of the coronary plaque were recently shown to be associated with its symptomatic rupture/thrombosis risk. Safety of the significant carotid plaque IVUS imaging in a large unselected population is unknown.
  
  
  METHODS
  We prospectively evaluated the safety of embolic protection device (EPD)-assisted vs. unprotected ICA-IVUS in a series of consecutive subjects with ≥ 50% ICA stenosis referred for carotid artery stenting (CAS), including 104 asymptomatic (aS) and 187 symptomatic (S) subjects (age 47-83 y, 187 men). EPD use was optional for IVUS, but mandatory for CAS.
  
  
  RESULTS
  Evaluation was performed of 107 ICAs (36.8%) without EPD and 184 with EPD. Lesions imaged under EPD were overall more severe (peak-systolic velocity 2.97 ± 0.08 vs. 2.20 ± 0.08 m/s, end-diastolic velocity 1.0 ± 0.04 vs. 0.7 ± 0.03 m/s, stenosis severity of 85.7 ± 0.5% vs. 77.7 ± 0.6% by catheter angiography; mean ± SEM; p<0.01 for all comparisons) and more frequently S (50.0% vs. 34.6%, p=0.01). No ICA perforation or dissection, and no major stroke or death occurred. There was no IVUS-triggered cerebral embolization. In the procedures of (i) unprotected IVUS and no CAS, (ii) unprotected IVUS followed by CAS (filters - 39, flow reversal/blockade - 3), (iii) EPD-protected (filters - 135, flow reversal/blockade - 48) IVUS + CAS, TIA occurred in 1.5% vs. 4.8% vs. 2.7%, respectively, and minor stroke in 0% vs. 2.4% vs. 2.1%, respectively. EPD intolerance (on-filter ICA spasm or flow reversal/blockade intolerance) occurred in 9/225 (4.0%). IVUS increased the procedure duration by 7.27 ± 0.19 min.
  
  
  CONCLUSIONS
  Carotid IVUS is safe and, for the less severe lesions in particular, it may not require mandatory EPD use. High-risk lesions can be safely evaluated with IVUS under flow reversal/blockade.
authors.affiliation: Department of Cardiac and Vascular Diseases, Jagiellonian University, Cracow, Poland. pmusialek@szpitaljp2.krakow.pl
authors.forename: Piotr
authors.initials: P
authors.lastname: Musialek
authors.forename: Piotr
authors.initials: P
authors.lastname: Pieniazek
authors.forename: Wieslawa
authors.initials: W
authors.lastname: Tracz
authors.forename: Lukasz
authors.initials: L
authors.lastname: Tekieli
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Przewlocki
authors.forename: Anna
authors.initials: A
authors.lastname: Kablak-Ziembicka
authors.forename: Rafal
authors.initials: R
authors.lastname: Motyl
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Moczulski
authors.forename: Jakub
authors.initials: J
authors.lastname: Stepniewski
authors.forename: Mariusz
authors.initials: M
authors.lastname: Trystula
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zajdel
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Roslawiecka
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Zmudka
authors.forename: Piotr
authors.initials: P
authors.lastname: Podolec
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000792:Angiography; D050197:Atherosclerosis / Q000000981:diagnostic imaging*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging*; D057505:Embolic Protection Devices; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography