Doppler tissue velocity sampling improves diagnostic accuracy during dobutamine stress echocardiography for the assessment of viable myocardium in patients with severe left ventricular dysfunction.
BACKGROUND
Both nuclear imaging with F18-fluorodeoxyglucose and dobutamine stress echocardiography have been used to identify viable myocardium, although dobutamine-stress echocardiography has been demonstrated to be the less sensitive of the two.


OBJECTIVE
To compare the accuracy of pulsed-wave Doppler tissue sampling with dobutamine-stress echocardiography for the detection of viable myocardium, using F18-fluorodeoxyglucose imaging as a reference. Methods Forty patients with chronic coronary artery disease and left ventricular dysfunction (mean ejection fraction 33+/-11%), underwent F18-fluorodeoxyglucose imaging, dobutamine-stress echocardiography and pulsed-wave Doppler tissue sampling. Evaluation was performed using a six-segment model.


RESULTS
Visual assessment by resting echo was feasible in 230 out of 240 segments (96%); 177 (77%) segments showed severe dyssynergy at rest. F18-fluorodeoxyglucose imaging showed viability in 95 (54%) segments while 82 (46%) were non-viable. Ejection phase velocity at rest was not significantly different; ejection velocities during low-dose and peak-dose dobutamine, however, were significantly higher in viable myocardium (8.6+/-2.9 vs 6.0+/-1.8 and 9.3+/-3.1 vs 6.2+/-2.1 cm x s(-1)). Using receiver operating characteristic curves the optimal cut-off value for viability assessment was an increase in the ejection phase velocity low-dose of 1+/-0.5 cm x s(-1), while 0+/-0.5 cm x s(-1)predicted non-viability. The sensitivity and specificity (95%CI) of pulsed-wave Doppler tissue sampling and dobutamine-stress echocardiography for the prediction of viability was respectively 87% (82-92) vs 75% (67-81) (P<0.05) and 52% (44-59) vs 51% (45-59) (P=ns).


CONCLUSIONS
The sensitivity of pulsed-wave Doppler tissue sampling is superior to dobutamine-stress echocardiography for the assessment of myocardial viability.
Rambaldi
R
R
Department of Cardiology, Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands.
Poldermans
D
D
Bax
J J
JJ
Boersma
E
E
Elhendy
A
A
Vletter
W
W
Roelandt
J R
JR
Valkema
R
R
D004280:Dobutamine / Q000008:administration & dosage; D018619:Echocardiography, Doppler, Pulsed; D005080:Exercise Test / Q000379:methods; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000008:administration & dosage; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology*; D015588:Observer Variation; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000503:physiopathology
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D004280:Dobutamine