Quantitative assessment of myocardial perfusion defects with real-time three-dimensional myocardial contrast echocardiography.
OBJECTIVE
To evaluate the feasibility and accuracy of measurement of myocardial perfusion defects with intravenous contrast-enhanced real-time three-dimensional echocardiography (CE-RT3DE).


METHODS
RT3DE was performed in 21 open-chest mongrel dogs undergoing acute ligation of the left anterior descending artery (LAD, n = 14) or distal branch of the left circumflex artery (LCX, n = 7). A perfluorocarbon microbubble contrast agent was injected intravenously to assess the resulting myocardial perfusion defects with Philips Sonos-7500 ultrasound system. Evans blue dye was injected into the occluded coronary artery for subsequent anatomic identification of underperfused myocardium. In vitro anatomic measurement of myocardial mass after removal of the animal's heart was regarded as the control. Blinded off-line calculation of left ventricular mass and perfusion defect mass from RT3DE images were performed using an interactive aided-manual tracing technique.


RESULTS
Total left ventricular (LV) myocardial mass ranged from 38.9 to 78.5 (mean +/- SD: 60.0 +/- 10.1) g. The mass of perfusion defect ranged from 0 to 21.4 (mean +/- SD: 12.0 +/- 5.0) g or 0 to 27% of total LV mass (mean +/- SD: 19% +/- 6%). The RT3DE estimation of total LV mass (mean +/- SD: 59.8 +/- 9.9 g) strongly correlated with the anatomic measurement (r = 0.98; y = 2.01 + 0.96x). The CE-RT3DE calculation of the mass of underperfused myocardium (mean +/- SD: 12. 3 +/- 5.3 g) also strongly correlated with the anatomic measurement (r = 0. 96; y = - 0.10 + 1.04x) and when expressed as percentage of total LV mass (r = 0.95; y = -0.20 + 1.04x).


CONCLUSIONS
RT3DE with myocardial contrast opacification could accurately estimate underperfused myocardial mass in dogs of acute coronary occlusion and would play an important role in quantitative assessment of myocardial perfusion defects in patients with coronary artery disease.
Zhuang
Lei
L
Department of Medical Imaging, Urumqi General Hospital of People's Liberation Army, Urumqi 830000. zlecg@163.com
Xie
Ming-xing
MX
Wang
Wei-juan
WJ
Yang
Xiang-xin
XX
Liu
Tao
T
D000818:Animals; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D004285:Dogs; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005070:Evans Blue; D005240:Feasibility Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D016277:Ventricular Function, Left / Q000502:physiology*
D005070:Evans Blue