Early and late diastolic strain rate vs global longitudinal strain at rest and during dobutamine stress for the assessment of significant coronary artery stenosis in patients with a moderate and high probability of coronary artery disease.

BACKGROUND: The aim of this prospective study was to assess the usefulness of global longitudinal strain (GLS), regional diastolic and systolic strain, strain rate (SR) parameters at rest and during dobutamine stress echocardiography for detecting significant coronary artery stenosis in patients with a moderate or high probability of coronary artery disease (CAD).
METHODS: Dobutamine stress echocardiography and adenosine magnetic resonance imaging (AMRI) were performed on 127 patients with a moderate and high probability of CAD and left ventricle ejection fraction ≥55%. CAD was defined as ≥70% diameter stenosis on coronary angiography validated as hemodynamically significant by AMRI. Patients were grouped according to coronary angiography and AMRI results: CAD (-) n=67 (52.8%) vs CAD (+) n=60 (47.2%).
RESULTS: There were no significant differences of clinical characteristics, conventional echocardiography, and deformation parameters between the two groups at rest except that GLS was higher in the CAD (-) group (-21.5±2.4% vs -16.2±2.1%, P=.00). GLS at high dobutamine doses had the highest area under the ROC curve (AUC) (AUC 0.955, sensitivity 94%, specificity 92%). Radial late diastolic SR at low doses performed best out of all diastolic parameters with an AUC of 0.789, sensitivity 76.7%, specificity 91.7%. Other deformation parameters including visual assessment were inferior.
CONCLUSIONS: Global longitudinal strain is highly sensitive and specific in detecting hemodynamically significant coronary artery stenosis in moderate- to high-risk patients without known CAD. This is the first study showing that GLS is more sensitive and specific compared with early and late diastolic SR parameters or visual assessment in detecting CAD.