Does resting echocardiography predict a positive response to subsequent low-dose dobutamine stress echocardiography in patients with ischaemic cardiomyopathy?

OBJECTIVE

dobutamine stress echocardiography (DSE) in patients with ischaemic cardiomyopathy. We explored the accuracy of resting echocardiographic and tissue Doppler parameters to predict a positive response by low-dose

METHODS AND

RESULTS

We enrolled 100 consecutive patients with prior myocardial infarction, and a left ventricular ejection fraction (LVEF) < 35%. They underwent resting echocardiographic assessment of LVEF, wall motion score index (WMSI), mitral E and A peak velocities, E/A ratio, E peak deceleration time, isovolumetric relaxation time (IVRT), early mitral annular diastolic velocity (e'), and E/e' ratio. Subsequently, they underwent low-dose DSE for assessment of myocardial viability. The presence of viability was defined by improvement of the regional wall motion score by > or =1 grade in > or = 5 myocardial segments, with > or = 20% reduction in WMSI compared with baseline evaluation. Thirty-six patients had a negative response to DSE (group 1); 64 had a positive response (group II). Resting LVEF was higher, and resting WMSI lower in group II versus group I; E peak deceleration time and IVRT shorter in group I (P < 0.05 for all). Multivariable regression analysis identified LVEF, WMSI, and IVRT as the independent predictors of a positive response to DSE. A cutoff value of LVEF of > 25% predicted viability with a sensitivity of 85.9%, specificity 80.6%; WMSI of < or = 2.6 had a sensitivity of 85.7%, specificity 61.1%; IVRT of > 60 msec had a sensitivity of 93.7%, specificity 47.2%.

CONCLUSIONS

Resting LVEF > 25%, WMSI < 2.6, and IVRT > 60 msec predicted viability with a high sensitivity; however, with the exception of LVEF, specificity was quite low.