Indicators of global myocardial work of the left ventricle during exercise stress echocardiography in the diagnosis of stable coronary heart disease

Abstract

Aim: To determine the possibility of identifying patients with significant coronary artery disease (CAD) by evaluation of the global left ventricular (LV) myocardial work indicators by constructing pressure-strain loops during exercise stress echocardiography.Material and Methods. The study included 136 patients aged 36 to 84 years, of which 97 (71%) men, with suspected or previously confirmed CAD, who underwent stress echocardiography on the treadmill according to the Bruce protocol. LV myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW) and global myocardial work efficiency (GWE) were evaluated using the technique of constructing pressure-strain loops at rest and at peak exercise. All patients underwent selective coronary angiography, according to the results of which they were divided into 3 groups: 51 patients without coronary artery lesions – the control group, 57 patients with single-vessel CAD and 28 patients with multi-vessel CAD. Significant lesion was defined as ≥ 70% artery luminal narrowing. All tests were two-sided and P-values < 0.05 were considered statistically significant.Results. Compared with the control group, patients with single-vessel CAD at rest had significantly less GWE and more GWW. In these patients GWI, GCW and GWE at peak exercise were significantly lower, and GWW was significantly higher. In patients with multi-vessel CAD, all global LV myocardial work indicators significantly differed from the control group both at rest and at peak exercise. The optimal cutoff value of GWI at peak exercise to predict significant CAD was 2553 mmHg% with a sensitivity of 62% and a specificity of 95% (AUC 0.79 ± 0.05, p < 0.001).Conclusions. The evaluation of global LV myocardial work indicators by constructing pressure-strain loops can be used in exercise stress echocardiography to improve the selection of patients requiring coronary intervention.