Prediction of transmural extent of infarction with contrast echocardiographically derived index of myocardial blood flow and myocardial blood volume fraction: comparison with contrast-enhanced magnetic resonance imaging.
BACKGROUND
We sought to determine the accuracy of myocardial contrast echocardiography (MCE)-derived index of myocardial blood flow and myocardial blood volume fraction (MBVF) in predicting transmural extent of infarction and wall-motion recovery.


METHODS
Low and high mechanical index MCE and contrast-enhanced magnetic resonance imaging were performed 5 to 7 days after successful percutaneous revascularization in 30 patients with acute myocardial infarction and regional wall-motion change was assessed 3 months later. The index of myocardial blood flow was calculated as A x beta (dB/s) using the equation y = A (1 - e(-beta t)), which fits the replenishment curve of low mechanical index MCE. The MBVF (mL/100 g myocardium) was calculated as 100 x 10(relative contrast intensity [CI]/10), using the relative CI by subtracting the cavity CI from the adjacent transmural CI using high mechanical index MCE. The contrast-enhanced magnetic resonance imaging-derived transmural extent of delayed hyperenhancement (DE) in 16 segments were measured and compared with corresponding MCE data.


RESULTS
Among 480 segments, 382 measurable segments were subdivided into 5 groups as follows: no DE, 1% to 25% DE, 26% to 50% DE, 51% to 75% DE, and 76% to 100% DE. An increment of the extent of DE was significantly related to a decrement of A x beta (P < .001) and MBVF (P < .001). The optimal cut-off MBVF for predicting greater than 50% DE was 1.92 mL (sensitivity 82%, specificity 73%, P < .01), and persistently dysfunctional motion was 1.81 mL (sensitivity 74%, specificity 75%, P < .01).


CONCLUSIONS
The MCE-derived A x beta and MBVF can be effective predictors of transmural extent of infarction and wall-motion recovery in the reperfused acute myocardial infarction.
Choi
Eui-Young
EY
Cardiology Division, Yonsei Cardiovascular Center and Cardiovascular Research Institute, Yonsei University College of Medicine, Seoul, South Korea.
Seo
Hye-Sun
HS
Park
Sungha
S
Kim
Hyun-Joo
HJ
Ahn
Jeong-Ah
JA
Ko
Young-Guk
YG
Choi
Byoung-Wook
BW
Kang
Seok-Min
SM
Choi
Donghoon
D
Ha
Jong-Won
JW
Rim
Se-Joong
SJ
Jang
Yangsoo
Y
Chung
Namsik
N
D001783:Blood Flow Velocity; D001810:Blood Volume; D003287:Contrast Media; D003326:Coronary Circulation; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000145:classification / Q000150:complications / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018487:Ventricular Dysfunction, Left / Q000145:classification / Q000175:diagnosis* / Q000209:etiology
D003287:Contrast Media