The diagnostic role of myocardial work indices in stable coronary disease - global wasted work as a novel important non-invasive parameter?

Abstract Introduction Although the non-invasive diagnostic tools for stable coronary artery disease (CAD) have developed significantly over the past years, there is no resting parameter available to recognize functionally significant CAD. The role of the novel myocardial work index (myocardial work index - MWI) calculated by the pressure-strain loop created with the help of speckle-tracking analysis and blood pressure measurement in the diagnosis of ischemic heart disease is not yet fully clarified. In our research, we examined the parameters of myocardial work analysis in stable coronary disease patients. Purpose Clarification of the diagnostic role of the myocardial work analysis, in patients with stable coronary artery disease. Methods In our prospective, single-center study, we examined 13 patients who had at least moderate stenosis (≥50%) in one main coronary branch detected on coronary CTA. A fractional flow reserve (FFR) test was performed for functional coronary assessment. Based on this measurement, we divided our patients into FFRneg (FFR value>0.8) and FFRpos groups. Echocardiography was performed before coronary angiography in all patients. In addition to the standard echocardiographic parameters, global myocardial work index (GWI), global constructive work (GCW) and global wasted work (GWW) were calculated. In the case of the FFRpos group, we performed the above examination both before and after revascularization (2 months). Results Our results show that neither the standard parameters (GLS, EF), nor the GWI and GCW showed any difference between the FFRpos and FFRneg groups. However, there was a significant difference regarding GWW (172.3±21.8 FFRneg vs. 258.2±38.4 FFRpos, p=0.048) at baseline. In the case of the FFRpos group, the analysis of our data showed that there was no significant difference in EF, GLS, GWI and GWE parameters before and after revascularization. However, global wasted work (GWW) showed a significant improvement after revascularization (preGWW 258.2±38.4 vs. postGWW 139.5±14.5, p=0.041). NT-proBNP levels were normal in our patient population and we could not detect. Conclusion Based on our results, the GWW may be suitable for non-invasive assessment of the functional significance of stable coronary disease, as it showed a significant difference in the case of functionally significant and non-significant stenosis and improved after revascularization in patients with single-vessel CAD.