title: The incidence of slow flow after rotational atherectomy of calcified coronary arteries: A randomized study of low speed versus high speed.
abstract: OBJECTIVE
  The purpose of this randomized trial was to compare the incidence of slow flow between low-speed and high-speed rotational atherectomy (RA) of calcified coronary lesions.
  
  
  BACKGROUND
  Preclinical studies suggest that slow flow is less frequently observed with low-speed than high-speed RA because of less platelet aggregation with low-speed RA.
  
  
  METHODS
  This was a prospective, randomized, single center study. A total of 100 patients with calcified coronary lesions were enrolled and randomly assigned in a 1:1 ratio to low-speed (140,000 rpm) or high-speed (190,000 rpm) RA. The primary endpoint was the occurrence of slow flow following RA. Slow flow was defined as slow or absent distal runoff (Thrombolysis in Myocardial Infarction [TIMI] flow grade ≤ 2).
  
  
  RESULTS
  The incidence of slow flow in the low-speed group (24%) was the same as that in the high-speed group (24%) (P = 1.00; odds ratio, 1.00; 95% confidence interval, 0.40-2.50). The frequencies of TIMI 3, TIMI 2, TIMI 1, and TIMI 0 flow grades were similar between the low-speed (TIMI 3, 76%; TIMI 2, 14%; TIMI 1, 8%; TIMI 0, 2%) and high-speed (TIMI 3, 76%; TIMI 2, 14%; TIMI 1, 10%; TIMI 0, 0%) groups (P = 0.77 for trend). The incidence of periprocedural myocardial infarction was the same between the low-speed (6%) and high-speed (6%) groups (P = 1.00).
  
  
  CONCLUSIONS
  This randomized trial did not show a reduction in the incidence of slow flow following low-speed RA as compared with high-speed RA (UMIN ID: UMIN000015702). © 2016 Wiley Periodicals, Inc.
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sakakura
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Funayama
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Taniguchi
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Tsurumaki
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Kei
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Mitsunari
authors.initials: M
authors.lastname: Matsumoto
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Wada
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Shin-Ichi
authors.initials: SI
authors.lastname: Momomura
authors.affiliation: Division of Cardiovascular Medicine, Saitama Medical Center, Jichi Medical University, 1-847 Amanuma, Omiya, Saitama City, Japan, 330-8503.
authors.forename: Hideo
authors.initials: H
authors.lastname: Fujita
mesh_terms: D017225:Atherectomy, Coronary / Q000009:adverse effects* / Q000379:methods; D002114:Calcinosis / Q000175:diagnosis / Q000601:surgery*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000601:surgery*; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D005500:Follow-Up Studies; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D054318:No-Reflow Phenomenon / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D011183:Postoperative Complications / Q000453:epidemiology*; D011446:Prospective Studies; D013997:Time Factors
keywords: high-speed; low-speed; randomized trial; rotational atherectomy; slow flow