Assessment of Postsystolic Shortening and Global Longitudinal Strain Improves the Sensitivity of Dobutamine Stress Echocardiography in End-Stage Liver Disease

Abstract

Dobutamine stress echocardiography (DSE) remains a widely used method for detection of coronary artery disease (CAD) in patients with end stage liver disease (ESLD) despite low sensitivity. Speckle tracking assessment of strain may enhance the sensitivity of DSE in the general population but the value of strain analysis in ESLD is unknown. DSE with two-dimensional speckle tracking and quantitative coronary angiography were performed in 146 patients with ESLD. Thirty-six patients (25%) had CAD (> 50% diameter stenosis of a major vessel). Global longitudinal strain at rest (GLSr) and at peak stress (GLSp) and an index of post-systolic (PSSi) shortening ([maximal extent of shortening - extent of shortening in systole] / [extent of shortening in systole]) were determined. A PSSi of > 0.25 was considered evidence for CAD. ROC analysis was used to determine the optimal thresholds of GLSr and GLSp for CAD and to assess the diagnostic performance of wall motion assessment (WMA) and strain parameters. The sensitivity and specificity of WMA, GLSr, GLSp and PSSi were compared. Thirty-six patients (25%) had significant CAD. The areas under the curve (AUC) for WMA, GLSr, GLSp, and PSSi were 0.60, 0.72, 0.68, and 0.78, respectively. Visual assessment of wall motion (WMA) had a sensitivity of 28%. The sensitivity of each of the strain parameters, GLSr (53%, p =0.016), GLSp (69%, p =0.004), and PSSi (78%, p <0.001), exceeded the sensitivity for WMA. WMA specificity was 92% which exceeded the specificity for each of the strain parameters (GLSr 82%, p =0.037), GLSp 63%, p <0.001), and PSSi (78%, p = 0.009). Of the strain parameters, PSSi had the best balance between sensitivity and specificity (both 78%). Assessment of GLS and PSSi with DSE yields better sensitivity than WMA in ELSD patients. PSSi had the best diagnostic performance of all parameters in this population with a low prevalence of CAD.