Simultaneous Analysis of Two-Dimensional Strain, Coronary Flow Reserve and Wall Motion during Dipyridamole Stress Echocardiography. Comparative Outcomes.

pp. 499-506

Abstract

Background: Dipyridamole stress echo (DSE) is an accepted pharmacological test for the evaluation of patients with ischemic pathology; it is demonstrated that it is an ideal technique to combine the visual information of contractility with coronary flow reserve (CFR), but there is no information regarding the use of 2D-strain (two-dimensional deformation) for the diagnosis of myocardial ischemia, so its evaluation and the comparison of results with other methods for the determination of regional ischemia may be of singular practical interest.
Objective: To compare, during dipyridamole stress echo (DSE), the results of the visual analysis of wall contractility with the value of CFR of the anterior descending artery (ADA) and with the behaviour of longitudinal 2D-strain in the same area, using myocardial perfusion with simultaneous 99m Tc-sestamibi SPECT as gold standard for the diagnosis of ischemia.
Material and Methods: A total of 41 patients (16 men; mean age 68.5 years) referred for DSE were evaluated. The obtained longitudinal 2D-strain was averaged out in the 9 segments corresponding to the ADA from the three apical views both at rest and during stress, considering ischemia the reduction in deformation or an increase lower than 5%. At the peak effect of 0.84 mg/kg of dipyridamole, wall motion and CFR of the ADA (normal: >2) were evaluated, and 99m Tc-sestamibi for stress SPECT was injected, completing its rest view at 24–48 hours.
Results: A total of 3 patients were excluded, one due to weak signal in the ADA and two due to suboptimal window for 2D-strain. Twelve patients with reversible defects with SPECT were considered ischemic. There was agreement in the four parameters evaluated in 6 patients with all abnormal studies and in 23 with all normal studies. Longitudinal deformation in the ADA area in patients with normal SPECT was –19.9 (–18, –22) at rest and –22.5 (–21, –26) at the peak of dipyridamole stress echo (p=0.0003). In patients with ischemic SPECT, 2D-strain was –19.35 (–17, –22) at rest and –20.25 (–13, –21) at the peak of dipyridamole stress echo (p=ns). CFR showed a sensitivity of 66.7% (HF 95% 35.4–88.7) and a specificity of 100%; 2D-strain showed a sensitivity of 83.3% (HF 95% 50.9–97) and a specificity of 88.5% (HF 95% 68.7–97).
Conclusions: 2D-strain during dipyridamole stress echo proved to be a feasible quantitative method with similar effectiveness to CFR and superior to visual contractility analysis for detecting ischemia in the ADA territory.