Myocardial contrast echocardiography assessment of acute changes in collateral perfusion of contralateral coronary artery with coronary flow reserve after coronary angioplasty.
BACKGROUND
Coronary flow velocity reserve (CFVR) is used to evaluate the severity of epicardial and intramyocardial coronary artery disease. Collateral flow to an adjacent compromised myocardial territory may influence the CFVR of a specific artery.


METHODS
To assess the impact of collateral flow on CFVR, we measured CFVR and assessed perfusion area (PA) with myocardial contrast echocardiography in the right coronary arteries of 18 patients with total/subtotal occlusion of the left anterior descending coronary artery before and after angioplasty. A total of 10 patients had well-developed collaterals emerging from the right coronary artery (group I) and 8 patients did not (group II). Using a Doppler-tipped guidewire, we measured CFVR, which is defined as the ratio of papaverine-induced hyperemic average peak velocity of coronary flow to baseline.


RESULTS
Before angioplasty of the left anterior descending coronary artery, CFVR was significantly reduced in group I compared with group II (2.35 +/- 0.47 vs 3.26 +/- 0.54, P < .01). Baseline average peak velocity in group I before angioplasty was significantly greater than that after angioplasty (23.7 +/- 11.6 vs 19.2 +/- 9.7 cm/s, P < .05). After angioplasty, CFVR immediately increased in group I to 3.46 +/- 0.54 ( P < .001). The increase in CFVR was well correlated with the decrement in PA after angioplasty (r = 0.883, P < .001).


CONCLUSIONS
The CFVR of an artery that supplies extensive collaterals is limited because of an elevation in the baseline resting flow velocity. This restriction in CFVR improves proportionally with decreases in PA that occurs after angioplasty of the ipsilateral coronary artery. These data suggest that PA, in addition to coronary artery structure, influences CFVR.
School of Allied Health Sciences, Osaka University, Faculty of Medicine, Osaka, Japan. ishikura@sahs.med.osaka-u.ac.jp
Fuminobu
F
Ishikura
Yasuhiko
Y
Sakata
Yasushi
Y
Sakata
Atsushi
A
Hirayama
Shintaro
S
Beppu
Kazuhisa
K
Kodama
D000208:Acute Disease; D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D001783:Blood Flow Velocity; D003097:Collateral Circulation; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000601:surgery*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016896:Treatment Outcome