Strain rate measurement by doppler echocardiography allows improved assessment of myocardial viability inpatients with depressed left ventricular function.
OBJECTIVE
This study sought to evaluate whether objective assessment of the myocardial functional reserve, using strain rate imaging (SRI), allows accurate detection of viable myocardium.


BACKGROUND
Strain rate imaging is a new echocardiographic modality that allows quantitative assessment of segmental myocardial contractility.


METHODS
In 37 patients (age 58 +/- 9 years) with ischemic left ventricular dysfunction, myocardial viability was assessed using low-dose (10 microg/kg body weight per min) two-dimensional dobutamine stress echocardiography (DSE), tissue Doppler imaging, SRI and (18)F-fluorodeoxyglucose ((18)FDG) positron emission tomography (PET). The peak systolic tissue Doppler velocity and peak systolic myocardial strain rate were determined at baseline and during low-dose dobutamine stress from the apical views.


RESULTS
A total of 192 segments with dyssynergy at rest were classified by (18)FDG PET as viable in 94 and nonviable in 98. An increase of peak systolic strain rate from rest to dobutamine stimulation by more than -0.23 1/s allowed accurate discrimination of viable from nonviable myocardium, as determined by (18)FDG PET with a sensitivity of 83% and a specificity of 84%. Receiver operating characteristic (ROC) curve analysis showed an area under the curve for prediction of nonviable myocardium, as determined by (18)FDG PET using SRI, of 0.89 (95% confidence interval [CI] 0.88 to 0.90), whereas the area under the ROC curve using tissue Doppler imaging was 0.63 (95% CI 0.61 to 0.65).


CONCLUSIONS
The increase in the peak systolic strain rate during low-dose dobutamine stimulation allows accurate discrimination between different myocardial viability states. Strain rate imaging is superior to two-dimensional DSE and tissue Doppler imaging for the assessment of myocardial viability.
Hoffmann
Rainer
R
Medical Clinic I, University Rheinisch Westfälische Technische Hochschule, Aachen, Germany. Rhof@pcserver.mk1.rwth-aachen.de
Altiok
Ertunc
E
Nowak
Bernd
B
Heussen
Nicole
N
Kühl
Harald
H
Kaiser
Hans Jürgen
HJ
Büll
Udalrich
U
Hanrath
Peter
P
D000368:Aged; D023921:Coronary Stenosis / Q000150:complications / Q000175:diagnosis; D004280:Dobutamine; D015150:Echocardiography, Doppler; D025401:Echocardiography, Stress; D005260:Female; D019788:Fluorodeoxyglucose F18; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D014055:Tomography, Emission-Computed; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000175:diagnosis*
D019788:Fluorodeoxyglucose F18; D004280:Dobutamine