Left Ventricular Long-Axis Function During Dobutamine Stress Echocardiography for the Prediction of Post-Revascularization Recovery: Comparison with SPECT Thallium Scintigraphy
Aim: Το compare echocardiographic left ventricular (LV) long axis function and single photon emission computed tomography (SPECT) thallium-201 scintigraphy for the prediction of recovery of LV dyssynergies after revascularization. Methods: Thirty patients with a history of previous myocardial infarction and LV dys-function underwent a transthoracic echocardiographic study before and after successful revascularization (101±14 days), in order to evaluate post-revascularization recovery of
... recovery of asynergic myocardial walls. In these patients and in 25 age-and sex-matched healthy subjects, an additional study during dobutamine infusion was also performed. All subjects also underwent SPECT thallium-201 scintigraphy. Prior and during dobutamine infusion the LV systolic atrioventricular (AV) plane displacement was recorded from the apical four and two chamber views, by M-Mode, at four LV sites, corresponding to the septal, lateral, anterior and inferior walls. Results: Healthy subjects showed a significant increase in AV displacement at all LV sites during dobutamine infusion (p<0.001). However, patients exhibited a significant increase in AV displacement during dobutamine infusion, only in the asynergic sites, with functional improvement in the post-revascularization echocardiogram (p<0.001). In the remaining asynergic sites, the AV displacement did not change (p>0.05). Selecting a maximum LV systolic AV displacement increase of >2 mm, the method proved to have a sensitivity of 91%, specificity of 83%, positive predictive value of 88% and negative predictive value of 87%. When SPECT thallium scans were used, the above indices were 86%, 65%, 74% and 79% respectively. Conclusion: The assessment of LV long axis function with the measurement of left systolic AV plane displacement during dobutamine infusion constitutes a simple and accurate method, better than SPECT thalium images, for the prediction of recovery of LV asynergy after revascularization.