Advances in stress echocardiography: myocardial work for myocardial ischemia detection

Aims: This study explores the usefulness of myocardial work (MW) analysis for coronary artery disease (CAD) detection in patients undergoing dipyridamole stress echocardiography (Dip-SE). Methods: We included 50 patients subjected to Dip-SE followed by coronary computed tomography angiography (CCTA) and/or invasive coronary angiography (ICA). Patients were subdivided into two groups, according to the results of CCTA/ICA: group 1 with CAD and group 2 without CAD. Subsequently, global longitudinal strain (GLS) and MW parameters were evaluated retrospectively at base, low and high dose in the entire population. Results: GLS showed a nonsignificant increase from baseline to low dose and significantly decreased from low to high dose (P = 0.015) in group 1. In contrast, GLS in group 2 increased throughout the test, with the largest increase from baseline to low dose (P < 0.001). Global constructive work (GCW) and global wasted work (GWW) showed opposite behaviors in both groups: GCW decreased in group 1 (P = 0.009) and remained substantially unchanged in group 2; conversely, GWW increased from low to high dose in group 1 (P = 0.003), whereas it decreased in group 2 (P = 0.047). The latter result was confirmed by global work efficiency (GWE), which decreased from low to high dose in group 1 (P = 0.025) and increased in group 2 (P = 0.001). Receiver-operating characteristics analysis revealed that GWE is the best parameter for identifying CAD (area under the curve = 0.845). A decrease in GWE of 1.5% (from low to high dose) provided better sensitivity (73%) and specificity (84%). Conclusions: GWE analysis may be useful in improving CAD detection during Dip-SE.