BACKGROUND: The aim of this study was to investigate the incremental value of global longitudinal strain (GLS) by automated function imaging in respect to wall motion (WM) for the detection of coronary artery disease (CAD) during dipyridamole stress echocardiography.
METHODS: Fifty-two patients (mean age, 65.3 ± 8.7 years; 22 men) underwent dipyridamole stress echocardiography followed by coronary angiography within 1 week. Diagnostic accuracy for the identification of single-vessel CAD was evaluated for WM and GLS. The study population was divided into two groups according to coronary angiographic findings: those with CAD (n = 38; mean age, 67.2 ± 5.9 years; 19 men) and those without CAD (n = 14; mean age, 63.3 ± 6.4 years; three men).
RESULTS: A trend toward lower resting GLS values was found in patients with CAD than in those without (-18.7 ± 2.2% vs -20 ± 2.8%, P = .061). In patients without CAD, GLS progressively increased up to peak dose (from -20 ± 2.8% at rest to -20.7 ± 1.9% at low dose, P = .045; from -20.7 ± 1.9% at low dose to -21.5 ± 3.1% at peak dose, P = .032), whereas in patients with CAD, an increase of GLS from rest to low dose (from -18.7 ± 2.2% to -19.2 ± 3.9%, P = .046) followed by a decrease from low to peak dose (from -19.2 ± 3.9% to -17.5 ± 2.4%, P = .007) was observed. In addition, with regard to diagnostic accuracy in detecting CAD, WM yielded sensitivity of 44%, specificity of 55%, positive predictive value of 73%, and negative predictive value of 26%, whereas GLS, alternatively evaluated as the difference between peak dose and resting values or between peak and low-dose values, provided sensitivity of 61%, specificity of 90%, positive predictive value of 94%, and negative predictive value of 47% (respectively, P = .020, P = .001, P = .023, and P = .031, all vs WM) and sensitivity of 84%, specificity of 92%, positive predictive value of 96%, and negative predictive value of 68% (respectively, P < .001, P < .001, P = .001, P < .001, all vs WM).
CONCLUSIONS: GLS analysis, particularly performed by comparing peak-dose with low-dose values, improves the accuracy of dipyridamole stress echocardiography in the detection of single-vessel CAD compared with the sole assessment of WM changes.
Aurora Cardiovascular Services, Aurora Sinai/Aurora St Luke’s Medical Centers