Can ischemia and dyssynchrony be detected during early stages of dobutamine stress echocardiography by 2-dimensional speckle tracking echocardiography?

Strain and strain rate (SR) measured with 2-dimensional speckle tracking echocardiography (2-D STE) can quantitatively assess myocardial function. Our aim was to evaluate whether we could detect abnormalities in strain, strain rate, and dyssynchrony by applying 2-D STE in patients with severe coronary artery disease during early stages of dobutamine stress echocardiography. Thirty-four patients with angiographically documented severe 3-vessel coronary artery disease and preserved left ventricular ejection fraction were compared with 42 control patients without evidence of coronary artery disease. Circumferential and longitudinal strain, SR, and left ventricular synchrony using standard deviation (SD) of time to systolic peak strain and SR were analyzed with 2-D STE at rest and at intermediate doses of dobutamine stress echocardiography. Compared with control subjects, patients with coronary artery disease showed lower circumferential SR [-1.42 (0.34) s^-1 vs -1.64 (0.34) s^-1; P <.02] and significantly lower longitudinal strain [-15.41 % (3.52 %) vs -19.37 % (3.21 %); P <.001] and SR [-0.91 (0.18) s ^-1 vs -1.19 (0.24) s^-1; P <.001] at intermediate doses; these values were also compromised at peak dose. The SD of longitudinal time to systolic peak strain at intermediate dose was significantly greater in patients with coronary artery disease than in control patients [37.89 (12.32) vs 27.21 (10.86); P <.001]. The 2-D STE-derived strain and SR detected myocardial dysfunction and asynchrony in patients with coronary artery disease during intermediate doses of dobutamine stress, with minimal changes in regional wall motion abnormalities at this stage.