title: "Tardus and parvus" phenomenon in upper limb arteries for identifying subclavian arterial stenosis.
abstract: BACKGROUND
  The detection of subclavian artery (SCA) stenosis or occlusion is important, and an easy and accurate noninvasive screening method is needed.
  
  
  METHODS
  Pulsed Doppler spectra of bilateral SCA, vertebral arteries, axillary arteries, and brachial arteries were recorded and analyzed both in patients with SCA stenosis and healthy subjects.
  
  
  RESULTS
  Thirty-five patients showed SCA stenosis less than 80% (mean: 72 +/- 14%; Vmax: 450.1 +/- 101.5 cm/sec) and seven patients demonstrated one-side SCA occlusion. The Vmax, systolic acceleration (SA) and resistance index (RI) were much lower (parvus) while the acceleration time (AT) was much longer (tardus) in axillary and brachial arteries on the ipsilateral than those both on the contralateral and the control group (Axillary artery: Vmax: 31.3 +/- 11.8 vs. 62.0 +/- 24.1 and 85.8 +/- 14.3 cm/sec, P < 0.01; SA: 2.0 +/- 1.0 vs. 6.8 +/- 4.9 and 9.6 +/- 2.0 m/sec(2), P < 0.05; RI: 0.8 +/- 0.1 vs. 1.1 +/- 0.4 and 1.1 +/- 0.3, P < 0.01; AT: 141 +/- 34 vs. 86 +/- 26 and 76 +/- 9 ms, P < 0.01. Brachial artery: Vmax: 47.5 +/- 25.2 vs. 76.7 +/- 37.6 and 84.6 +/- 14.2 cm/sec, P < 0.05; SA: 3.1 +/- 2.1 vs. 9.1 +/- 5.2 and 10.1 +/- 3.5 m/sec(2), P < 0.01; RI: 1.0 +/- 0.1 vs. 1.2 +/- 0.1 and 1.2 +/- 0.1, P < 0.01; AT: 155 +/- 31 vs. 86 +/- 19 and 78 +/- 12ms, P < 0.01).
  
  
  CONCLUSIONS
  The "tardus and parvus" phenomenon in ipsilateral axillary and brachial arteries could be employed as an alternative method and a shortcut for detection of the SCA stenosis or occlusion.
authors.affiliation: Department of Ultrasound Diagnostics, Tangdu Hospital, Fourth Military Medical University, Xi'an, China. duanyy@fmmu.edu.cn
authors.forename: Yun-You
authors.initials: YY
authors.lastname: Duan
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Yuan
authors.forename: Kang
authors.initials: K
authors.lastname: Ding
authors.forename: Xi
authors.initials: X
authors.lastname: Liu
authors.forename: Fa-Qin
authors.initials: FQ
authors.lastname: Lv
authors.forename: Tie-Sheng
authors.initials: TS
authors.lastname: Cao
mesh_terms: D000328:Adult; D000368:Aged; D001132:Arm / Q000098:blood supply*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013349:Subclavian Steal Syndrome / Q000000981:diagnostic imaging*; D018615:Ultrasonography, Doppler, Color / Q000379:methods*