Automated assessment of myocardial viability after acute myocardial infarction by global longitudinal peak strain on low-dose dobutamine stress echocardiography.
BACKGROUND
Low-dose dobutamine stress echocardiography (DSE) assesses myocardial viability at the early stage of acute myocardial infarction (AMI), but its assessment is subjective and variable. Automated function image (AFI) determines global longitudinal peak strain (GLPS) based on tissue tracking technique. The ability of GLPS obtained by AFI during dobutamine stress to assess myocardial viability after AMI was investigated.


RESULTS
Low-dose DSE at day 3 in 23 consecutive patients with AMI was performed using Vivid 7 (GE Healthcare). Segmental longitudinal peak strain with AFI and obtained GLPS was analyzed. Wall motion score index (WMSI) by echocardiography 1 month later was determined. In 18 patients, left ventriculography was also performed at 3.2±1.5 months later to obtain left ventricular ejection fraction (LVEF) and regional wall motion (RWM, SD/chord). GLPS was improved during dobutamine infusion at 10 µg · kg(-1) · min(-1) (-12.9 ± 3.5% to -15.2 ± 3.6%, P=0.0004). GLPS during dobutamine stress showed good correlations with follow-up WMSI (R=0.47, P=0.02), with peak CK-MB (R = 0.52, P=0.01), with RWM (R = -0.48, P=0.04), and with LVEF (R = -0.54, P=0.02), whereas GLPS at baseline showed no correlations with them. Averaged segmental peak strain at baseline and during stress were correlated with follow-up WMSI (R = 0.50 and 0.43, respectively), but not with LVEF.


CONCLUSIONS
GLPS during dobutamine stress determined by AFI is a promising, objective index to assess myocardial viability on the early stage of AMI.
Iwakura
Katsuomi
K
Division of Cardiology, Sakurabashi Watanabe Hospital, Osaka, Japan. iwakura@mac.com
Okamura
Atsushi
A
Koyama
Yasushi
Y
Date
Motoo
M
Higuchi
Yoshiharu
Y
Inoue
Koichi
K
Kimura
Ryusuke
R
Nagai
Hiroyuki
H
Imai
Michio
M
Toyoshima
Yuko
Y
Ozawa
Makito
M
Ito
Norihisa
N
Okazaki
Yukinori
Y
Shibuya
Masahiko
M
Omiya
Shigemiki
S
Takagi
Takashi
T
Morisawa
Daisuke
D
Fujii
Kenshi
K
D000328:Adult; D000368:Aged; D001331:Automation; D002470:Cell Survival; D025401:Echocardiography, Stress / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000473:pathology; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000000981:diagnostic imaging*; D018570:Risk Assessment; D013318:Stroke Volume; D013997:Time Factors; D018487:Ventricular Dysfunction, Left