Global longitudinal strain aids the detection of non-obstructive coronary artery disease in the resting echocardiogram

Aims To evaluate the diagnostic power of abnormal global longitudinal strain (GLS) to detect non-obstructive coronary artery disease (CAD) in the resting echocardiogram. GLS using two-dimensional speckle-tracking echocardiography (2D STE) is a powerful tool for detecting advanced CAD. However, the diagnostic power of 2D STE for detecting moderate, clinically unapparent CAD from images obtained at rest is unknown. Methods and results We retrospectively studied 2D STE characteristics in 123 consecutive patients who underwent stress echocardiography, and subsequently coronary angiography within 10 days. We compared the diagnostic power of GLS at rest to the conventional wall motion score index (WMSI) during stress for detecting stenosis >= 50% (CAD(>50)) in any major coronary artery. Studies with akinetic or dyskinetic segments and reduced left ventricular ejection fraction were excluded. In 56 patients with significant CAD(>50), GLS was -16.77 +/- 3.18% compared with -19.05 +/- 3.43% in the 67 patients without CAD(<50) (P = 0.0002). A GLS cutpoint of greater than -17.77% had the most optimal sensitivity and specificity (66/76%) for detecting CAD and was comparable to a WMSI >= 1.13 (68/70%) measured during stress. Conclusion Non-obstructive CAD was identified by a reduced GLS measured by 2D STE in rest images with similar accuracy to the traditional WMSI measured in stress echocardiography.