Comparison of stress dobutamine echocardiography and stress dobutamine gated myocardial SPECT for the detection of viable myocardium

BACKGROUND: We prospectively studied a group of patients with myocardial infarction (MI), who were candidates for surgical revascularization, to compare the efficacy of dobutamine gated myocardial SPECT with dobutamine stress echocardiography (DSE) for the detection of myocardial viability. MATERIALS AND METHODS: We investigated 224 segments from 14 patients with MI using resting echocardiography and low dose dobutamine stress echocardiography as well as resting, low and high dose dobutamine stress 99mT c-Sestamibi gated SPECT. RESULTS: In total, 13 men and 1 women with a mean age 54.57 years (range, 43 to 71 years) entered the study. Of the 125 dysfunctional segments, as assessed by ECG-gated examination, 53 (23.66% of total) were hypokinetic at rest, 64 (28.57% of total) were akinetic, and 8 (3.57% of total) were dyskinetic. The number of segments with resting wall motion abnormality (considered viable by low dose dobutamine ECG-gated examination) was significantly greater than those showing a contractile improvement in response to dobutamine in echocardiography (39.2% versus 32.8%, respectively, p < 0.05). In addition, in high dose ECG-gated examination, 42 of the 125 dysfunctional segments (33.6%) were viable. In general, the methods were well correlated. CONCLUSION: We found a good agreement between low dose dobutamine gated SPECT and stress dobutamine echocardiography for the detection of inotropic reserve in infarcted areas.