Detection of functional recovery using low-dose dobutamine and myocardial contrast echocardiography after acute myocardial infarction treated with successful thrombolytic therapy.
OBJECTIVE
We studied the value of low-dose dobutamine stress echocardiography (LDDE) and myocardial contrast echocardiography (MCE) in early prediction of left ventricular functional recovery (LVFR) after acute myocardial infarction (AMI) treated with successful thrombolysis.


METHODS
LDDE and MCE using second-harmonic intermittent imaging were performed in first week after AMI. LVFR was defined as an absolute > or =5% increase in ejection fraction, from early to 6 months of follow-up by Technetium-99m-Sestamibi single-photon emission computed tomography.


METHODS
Out of 50 patients studied, 19 evolved with LVFR (group 1) and 31 without LVFR (group 2). Regional dysfunction was detected in 103 (37%) infarcted-related segments in group 1 and in 173 (63%) segments in group 2.


RESULTS
Sensitivity, specificity, positive, and negative predictive values and accuracy for detecting LVFR by LDDE were 94.7% (18/19), 87.1% (27/31), 81.8% (18/22), 96.4% (27/28), and 90% (45/50), respectively, and by MCE were 94.7% (18/19), 51.6% (16/31), 54.5% (18/33), 94.1% (16/17), and 68% (34/50). In group 1, functional improvement was observed in 86.9% (53/61) of segments with contractile reserve by LDDE and in 65.8% (52/79) of segments with microvascular perfusion by MCE. In group 2, functional improvement was observed in 78.3% (18/23) of segments with contractile reserve by LDDE and in 25.5% (25/98) of segments with microvascular perfusion by MCE. All segments without perfusion by MCE evolved without functional recovery.


CONCLUSIONS
LDDE was an accurate predictor of late left ventricular function recovery after AMI, while MCE was sensitive and has a high negative predictive value demonstrating that microvascular perfusion is essential for LVFR.
Sbano
João Cesar Nunes
JC
Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil.
Tsutsui
Jeane Mike
JM
Andrade
José Lazaro
JL
Carlos Nicolau
José
J
Meneghetti
José Claudio
JC
Franchini Ramires
José
J
Mathias
Wilson
W
D000368:Aged; D016009:Chi-Square Distribution; D003287:Contrast Media; D004452:Echocardiography; D025401:Echocardiography, Stress; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020127:Recovery of Function; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D015912:Thrombolytic Therapy; D015899:Tomography, Emission-Computed, Single-Photon
D003287:Contrast Media