Heterogeneity of myocardial perfusion in distal coronary embolism with different particle sizes.
BACKGROUND
We hypothesized that altered myocardial perfusion distribution patterns could be seen with coronary distal emboli of different particle sizes using myocardial contrast echocardiography.


METHODS
In 16 open-chest anesthetized dogs, microsphere suspensions of 9 or 500 microm in diameter were injected into the left anterior descending coronary artery until the mean left anterior descending coronary artery flow rate was reduced to less than 30% of baseline flow. During baseline conditions and after maximal embolization, real-time myocardial contrast echocardiography was performed by intravenous infusion of an echocontrast agent.


RESULTS
In animals infused with 9-microm microspheres, a transmural perfusion defect was seen at the time of maximal embolization. In contrast, in animals infused with 500-microm microspheres, a subendocardial perfusion defect was observed.


CONCLUSIONS
The particle size of coronary distal emboli affects myocardial perfusion distribution.
Akiyama
Maki
M
Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan. ma@med.kawasaki-m.ac.jp
Akasaka
Takashi
T
Fujimoto
Katsukuni
K
Koyama
Yuji
Y
Watanabe
Nozomi
N
Neishi
Yoji
Y
Tomita
Junko
J
Toyoda
Tomohiko
T
Kaji
Shuichiro
S
Yoshida
Kiyoshi
K
D000818:Animals; D021721:Balloon Occlusion / Q000379:methods*; D003326:Coronary Circulation; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004285:Dogs; D004452:Echocardiography / Q000379:methods*; D004617:Embolism / Q000000981:diagnostic imaging*; D007089:Image Enhancement / Q000379:methods*; D008863:Microspheres; D010316:Particle Size; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity