Abstract Background Dipyridamole stress echocardiography (DSE) is an established technique to detect coronary artery disease (CAD) and for risk stratification. Speckle Tracking Echocardiography (STE), as an objective and quantitative evaluation of ventricular function, may add incremental value to conventional stress echo analysis. Purpose To assess the prognostic value of rest (Rest-GLS) and peak (Peak-GLS) stress global longitudinal strain (GLS) in patients with suspected CAD and negative DSE according to wall motion index (WMI) criteria. Methods We retrospectively enrolled patients who underwent DSE at our centre for suspected CAD, with normal WMI. Strain Reserve was calculated as Rest GLS – Peak-GLS (Delta-GLS). We also collected data regarding other conventional parameters such as coronary flow reserve (CFR) of left anterior descending (LAD), left ventricle contractile reserve (LVCR), delta left ventricular ejection fraction (Delta-LVEF), heart rate response (HRR). Our primary endpoint was a composite of all-cause death and coronary revascularization. Receiver operating characteristic (ROC) curves were used to compare the predictive ability of the parameters. Adjusted logistic regression analyses were used to assess associations, also modelled as a restricted cubic spline. Results A total of 355 patients were included in the analysis (median age 68.2, IQR 58.2-75.2, 38.0% female). At follow-up, 58 patients met the primary endpoint. Figure 1 shows the ROC curves of different DSE parameters. Delta-GLS and Peak-GLS showed high predictive ability of composite endpoint events (area under the curve [AUC] 0.87, 95% Confidence Interval [CI] 0.82-0.92, AUC, 0.85, 95% CI 0.79-0.91, respectively), which was significantly higher compared with other DSE parameters, included Basal-GLS (P for difference for all < 0.001). After adjustments for age, previous CAD, sex, and diabetes, reducing values of Rest-GLS, Peak-GLS and Delta-GLS were significantly associated with higher odds of experiencing composite endpoint events (Basal-GLS, odds ratio [OR] 1.13, 95% CI 1.04-1.24; Peak-GLS, OR 1.45, 95% CI 1.32-1.63; Delta-GLS, OR 1.73, 95% CI 1.50-2.04). Plotting the results of the logistic regression analysis on a restricted cubic spline, reducing values of Peak-GLS and Delta-GLS showed a linear increase for the risk of adverse events, while Rest-GLS showed a plateau for lower values. Conclusion The use of GLS parameters in DSE can help to better stratify the risk for the patients since they are associated with adverse cardiovascular events.Figure 1Figure 2
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