title: Mechanism of increasing systolic coronary flow velocity in patients with aortic regurgitation.
abstract: OBJECTIVE
  The mechanism of increasing systolic coronary flow velocity of the epicardial coronary artery in patients with aortic regurgitation (AR) has not been well investigated. Thus, an evaluation was made of the flow velocity pattern of the epicardial coronary artery in these patients.
  
  
  METHODS
  In 12 patients with AR, epicardial coronary flow velocity was monitored using Doppler guidewire, and diameter changes of the epicardial coronary artery using intravascular ultrasound (IVUS).
  
  
  RESULTS
  The systolic coronary vascular resistance in AR patients was significantly less than that in controls (1.8 +/- 0.9 versus 3.3 +/- 0.7 mmHg/ml/min; p <0.01). Likewise, area and diameter changes of the epicardial coronary artery during the cardiac cycle in AR patients were significantly less than those in controls (102 +/- 1% versus 106 +/- 4%; p <0.01; and 102 +/- 1% versus 106 +/- 4%; p = 0.03).
  
  
  CONCLUSIONS
  In patients with AR, the increase in systolic coronary flow velocity of the epicardial coronary artery during the systolic phase was considered to result from a major coronary perfusion of blood into the intramyocardial vessels (which showed a decreased resistance), rather than it being stored in the epicardial coronary artery.
authors: Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan. tteru@med.kawasaki-m.ac.jp
authors: Teruyoshi
authors: T
authors: Kume
authors: Takahiro
authors: T
authors: Kawamoto
authors: Hiroyuki
authors: H
authors: Okura
authors: Nozomi
authors: N
authors: Watanabe
authors: Eiji
authors: E
authors: Toyota
authors: Yoji
authors: Y
authors: Neishi
authors: Renan
authors: R
authors: Sukmawan
authors: Ryotaro
authors: R
authors: Yamada
authors: Takashi
authors: T
authors: Akasaka
authors: Kiyoshi
authors: K
authors: Yoshida
mesh_terms: D000368:Aged; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology*; D001783:Blood Flow Velocity / Q000502:physiology*; D006328:Cardiac Catheterization; D003326:Coronary Circulation / Q000502:physiology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology*; D015150:Echocardiography, Doppler / Q000379:methods; D019160:Endosonography / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012720:Severity of Illness Index; D013599:Systole; D014655:Vascular Resistance / Q000502:physiology*