title: Vascular Assessment for Transcatheter Aortic Valve Replacement: Intravascular Ultrasound Compared With Computed Tomography.
abstract: BACKGROUND
  Assessment of the femoral and iliac arteries is essential prior to transcatheter aortic valve replacement (TAVR). It is critical for establishing candidacy for a femoral approach, and can help predict vascular complications. Although computed tomography angiography (CTA) is the standard imaging modality, it has limitations.
  
  
  OBJECTIVE
  This study compared CTA with intravascular ultrasound (IVUS) in patients undergoing TAVR evaluation.
  
  
  METHODS
  Fifteen patients undergoing pre-TAVR coronary angiography and hemodynamic assessment were recruited. Following coronary angiography, patients underwent distal aortography, bilateral iliac and femoral arteriography, and IVUS assessment. Vascular tortuosity, minimum lumen diameter, and cross-sectional area were obtained and the findings were compared with those obtained from CTA.
  
  
  RESULTS
  Correlation between IVUS and CTA was strong for minimum luminal diameter (r=0.62). Concordance was also strong between CTA and invasive iliofemoral angiography for assessment of tortuosity (r=0.75). Utilizing Bland-Altman analysis, vessel diameters obtained by IVUS were consistently greater than those obtained by CTA. The angiography and IVUS strategy was associated with a lower overall mean contrast utilization (29 cc vs 100 cc; P<.001), reduced mean radiation exposure (527 mGy vs 998 mGy; P=.045), and no significant difference in mean test duration (13.3 minutes vs 10 minutes; P=.12).
  
  
  CONCLUSIONS
  For femoral and iliac arterial assessment prior to TAVR, IVUS is a viable alternative to CTA with comparable accuracy, and the potential for less contrast use and less radiation exposure. IVUS is also a valuable adjunct to CTA in patients with borderline femoral access diameters or considerable CTA artifacts.
authors.forename: Essa
authors.initials: E
authors.lastname: Essa
authors.forename: Nader
authors.initials: N
authors.lastname: Makki
authors.forename: Peter
authors.initials: P
authors.lastname: Bittenbender
authors.forename: Quinn
authors.initials: Q
authors.lastname: Capers
authors.forename: Barry
authors.initials: B
authors.lastname: George
authors.forename: Gregory
authors.initials: G
authors.lastname: Rushing
authors.forename: Juan
authors.initials: J
authors.lastname: Crestanello
authors.forename: Konstantinos Dean
authors.initials: KD
authors.lastname: Boudoulas
authors.affiliation: Department of Cardiovascular Medicine, The Ohio State Wexner Medical Center, 410 W. 10th Ave, 1 Maloney Building, Columbus, OH 43210 USA. Scott.Lilly@osumc.edu.
authors.forename: Scott M
authors.initials: SM
authors.lastname: Lilly
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000150:complications / Q000601:surgery*; D001157:Arterial Occlusive Diseases / Q000150:complications / Q000175:diagnosis*; D057186:Comparative Effectiveness Research; D000072226:Computed Tomography Angiography / Q000379:methods*; D061827:Dimensional Measurement Accuracy; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging; D006801:Humans; D007083:Iliac Artery / Q000000981:diagnostic imaging; D008297:Male; D011183:Postoperative Complications / Q000517:prevention & control*; D011300:Preoperative Care / Q000379:methods; D020379:Risk Adjustment / Q000379:methods; D065467:Transcatheter Aortic Valve Replacement / Q000009:adverse effects / Q000379:methods; D018084:Ultrasonography, Interventional / Q000379:methods*; D054079:Vascular Malformations / Q000150:complications / Q000175:diagnosis*