Dobutamine stress echocardiography at 7.5 mu g/kg/min using color tissue Doppler imaging M-mode safely predicts reversible dysfunction early after reperfusion in patients with acute myocardial infarction

Dobutamine stress echocardiography (DSE) is widely used to predict reversib le left ventricular dysfunction, but evaluation by this method is subjectiv e. The recently developed color tissue Doppler imaging (TDI) M-mode; may pe rmit objective and quantitative assessment of changes in wall motion induce d by DSE. We rested the hypothesis that this new method can detect sensitiv ely reversible dysfunction in the post-myocardial infarction setting. DSE w ith color TDI M-mode and conventional DSE were performed to predict reversi ble dysfunction in 53 patients at a mean of 3 days after infarction using 7 .5 and 10 mu g/kg/min of dobutamine. Follow-up regular echocardiography (4 weeks later) was used as the reference technique to define reversible dysfu nction segments. To predict reversible dysfunction segments, the standard s egmental wall motion score change on conventional DSE and the ratio of the segmental wall velocity difference at rest versus stress (7.5 and 10 mu g/k g/min) on DSE with color TDI M-mode (7.5-TDI-M and 10-TDI-M, respectively) were used. With 7.5 mu g/kg/min of dobutamine, the sensitivity for predicti ng reversible dysfunction using color TDI M-mode (7.5-TDI-M) was significan tly higher than that of conventional DSE (89% vs 73%, p <0.05) whereas spec ificities and predictive values were almost identical. With a 10-mu g/kg/mi n dose, color TDI-M mode (10-TDI-M) and conventional DSE were not significa ntly different in predicting reversible dysfunction. With use of color TDI- M mode, regional wall motion during DSE was analyzed objectively and quanti tatively. Moreover, combined TDI-M and conventional data were slightly supe rior to either mode alone. There were no arrhythmias during 7.5 mu g/kg/min of dobutamine, but 9 arrhythmias occurred during the 10-mu g/kg/min dose i n patients with acute myocardial infarction. In conclusion, color TDI M-mod e permits objective and quantitative assessment of regional ventricular wal l motion and gives additional information for detecting reversible dysfunct ion in DSE. Improvement of sensitivity at a lower dose of dobutamine with c olor TDI-M mode may increase the safety of DSE in the post-myo-cardial infa rction setting. (C)1999 by Excerpta Medica, Inc.