[Comparison of dobutamine echocardiography and rest-redistribution 201-thallium SPECT in the assessment of myocardial viability taking PET as gold standard].
OBJECTIVE
To compare Tl-201 SPECT and dobutamine stress echocardiography for the detection of myocardial viability in patients with severe left ventricular dysfunction using metabolic imaging by positron emission tomography as the standard reference.


METHODS
We studied 25 consecutive patients with severe coronary artery disease and left ventricular dysfunction that underwent two different diagnostic modalities for evaluating myocardial viability: stress echocardiography with incremental doses of dobutamine from 5 up to 40 g/kg/min in 3 min stages, and 201 Tl SPECT using a rest-redistribution protocol with delayed images obtained at 4 hours. Fluorodeoxyglucose uptake by PET was used as the gold standard. Viability criteria were as follows, for 201Tl SPECT imaging: normal uptake at rest and presence of redistribution in the delayed images, for dobutamine stress echocardiography: sustained improvement and biphasic response.


RESULTS
Sensitivity of thallium redistribution was 46%, for normal uptake, plus redistribution 82%, 34% for dobutamine biphasic response and 58% for sustained improvement plus biphasic response. Specificity of biphasic response was 82% and that of redistribution 67%. Stepwise logistic regression indicated that biphasic wall motion response during dobutamine stress echocardiography (2.01 CI 95%; 1.10 to 3.99) and the presence of redistribution plus normal uptake at rest with thallium imaging (2.68 CI 95%; 1.42 to 5.13) were the best predictors of viability. These results were the same when both techniques were analyzed together.


CONCLUSIONS
Biphasic wall motion response during dobutamine stress echocardiography and the normal uptake plus presence of redistribution with thallium imaging were the best pre
Peral
V
V
Hospital Universitario Son Dureta.Palma de Mallorca, Spain.
Vilacosta
I
I
Fernández
C
C
Hernández
M
M
San Román
J A
JA
Batlle
E
E
Meroño
E
E
Carreras
J L
JL
Bethencourt
A
A
D002316:Cardiotonic Agents; D003430:Cross-Sectional Studies; D004280:Dobutamine; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012146:Rest; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*
D002316:Cardiotonic Agents; D013794:Thallium Radioisotopes; D004280:Dobutamine