Mechanism of increasing systolic coronary flow velocity in patients with aortic regurgitation.
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.
Kume
Teruyoshi
T
Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan. tteru@med.kawasaki-m.ac.jp
Kawamoto
Takahiro
T
Okura
Hiroyuki
H
Watanabe
Nozomi
N
Toyota
Eiji
E
Neishi
Yoji
Y
Sukmawan
Renan
R
Yamada
Ryotaro
R
Akasaka
Takashi
T
Yoshida
Kiyoshi
K
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*