Assessment of regional myocardial strain by a novel automated tracking system from digital image files.
Myocardial strain imaging by Doppler tissue echocardiography is a useful method to quantify regional left ventricular function. However, this method has a problem of its Doppler angle dependency. We attempted to quantify myocardial strain by a newly developed automated tracking system from digital image files. In 6 anesthetized open-chest dogs, a pair of ultrasonic crystals was implanted at the inner site and outer site of the left ventricular wall to measure myocardial radial strain. B-mode echocardiographic images and trajectories of crystals were recorded simultaneously. Three conditions were examined by intravenous infusion of dobutamine. We used a pattern matching algorithm, which allowed us to track objects from one frame to the next. In 18 image sequences obtained in the 6 dogs, there was an excellent correlation in maximal myocardial strain between the two methods ( r = 0.92, P < .0001). Thus, this system is a promising tool to provide automated quantification of regional myocardial strain.
Toyoda
Tomohiko
T
Department of Cardiology, Kawasaki Medical School, Kurashiki City, Japan.
Baba
Hirotaka
H
Akasaka
Takashi
T
Akiyama
Maki
M
Neishi
Yoji
Y
Tomita
Junko
J
Sukmawan
Renan
R
Koyama
Yuji
Y
Watanabe
Nozomi
N
Tamano
Satoshi
S
Shinomura
Ryuichi
R
Komuro
Issei
I
Yoshida
Kiyoshi
K
D000465:Algorithms; D000818:Animals; D004285:Dogs; D015150:Echocardiography, Doppler / Q000295:instrumentation / Q000379:methods*; D025401:Echocardiography, Stress / Q000295:instrumentation / Q000379:methods*; D005260:Female; D007091:Image Processing, Computer-Assisted; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D009206:Myocardium; D016277:Ventricular Function, Left / Q000502:physiology*