Early systolic mitral annular motion velocities responses to dobutamine infusion predict myocardial viability in patients with previous myocardial infarction

Objective This study was undertaken for the determination of the correlation between myocardial viability and regional systolic mitral annular motion velocity (MAV) response to dobutam\ine stress in patients with previous myocardial infarction (MI) with pulsed tissue Doppler scan imaging. Methods The study included 45 patients (mean age, 65 12 years) with previous MI with 1 major coronary lesion and 30 healthy individuals (mean age, 61 14 years). Tc-99m-metboxyisobutylisonitrile scintigraphy was performed to divide the patients into 2 groups: the viability (+) group (n = 25) and the viability (-) group (n = 20). Dobutamine was infused (at 2, 5, 10, and 20 mug/kg/min), and the peak first and second systolic MAVs (Sw(1) and SW2, respectively) were measured at the level of the mitral annulus corresponding to the infarct regions in the MI group and to the 6 mitral annular sites in the control group. In addition, the left ventricular wall motion score index (WMSI) was determined with 2-dimensional echocardiography. Results At baseline, the WMSI was significantly greater and the mean Sw(1) and Sw(2) were significantly lower in both the viability (+) and (-) groups than in the control group, but there were no significant differences between the viability (+) and (-) groups. After dobutamine infusion, the WMSI improved only in the viability (+) group. The mean Sw(1) and Sw(2) increased significantly with 2 pg/kg/min and 5 mug/kg/min of dobutamine, respectively, in the viability (+) group. With an increase in Sw(1) of 2.0 cm/s or more with 5 mug/kg/min of dobutamine, viable myocardium was detected, with a sensitivity of 92% and a specificity of 90%. There were no significant increases in Sw(1) or Sw(2) in the viability (-) group with dobutamine infusion. Conclusion Viable left ventricular myocardium is identified with peak early systolic MAV during dobutamine infusion.