Diagnostic Efficiency of Myocardial Work Indexes in Determining Myocardial Viability in Patients With Acute St-elevation Myocardial Infarction (Stemi): a Diagnostic Test Study.

Purpose To describe the diagnostic accuracy of myocardial work indices to identify myocardial viability in patients with STEMI and LVEF < 45%. Methods We studied 49 patients with STEMI and an ejection fraction < 45%. All of them underwent a myocardial viability study with cardiovascular magnetic resonance (CMR) using late gadolinium enhancement (viable tissue was defined as the presence of late enhancement < 50% of the myocardial thickness). At the same time, myocardial work indices were measured to identify the best cutoff point to determine viability, using CMR as the gold standard. We generated ROC curves and then calculated the sensitivity, specificity, and predictive values. Results Global constructive work had the best accuracy in the diagnosis of viability (AUC: 0.96. Specificity: 79%. Sensitivity: 97%, for a cutoff point > 786 mmHg%), compared with the Global Work Index (AUC: 0.96 Specificity: 91% Sensitivity: 79% at cutoff point > 664 mmHg%) and Global Myocardial Efficiency (AUC: 0.83 Specificity: 89% Sensitivity: 64% at a cutoff point > 75%); moreover, GCW was better than global longitudinal strain and biplanar ejection fraction of the left ventricle. Conclusion Myocardial work indices can detect viable myocardial tissue in patients with STEMI and left ventricular dysfunction with an acceptable degree of diagnostic accuracy.