New technologies in echocardiography enable timely management of NSTE-ACS today

Author(s): Fabio Capasso, Giuseppe Valva, Pietro Landino, Alfonsina Maria Abbondanza Corbisiero, Salvatore Severino, Lucrezia Delli Paoli, Filomena Pacelli, Francesco Renga, Vincenzo Sellitto, Giuseppe Gargiulo, Sara Iuliano, Maria Gabriella Grimaldi, Marco Pepe

An occluded vessel is the primary cause in one-third of Non-ST-segment Elevation Acute Coronary Syndrome (NSTE-ACS). Consequently, the identification of patients with a suspected occluded vessel as a distinct pathological scenario within the NSTE- ACS spectrum assumes essential importance to avert potentially detrimental delays in reestablishing coronary blood flow. The lack of electrocardiographic sensitivity in diagnosing an Acute Coronary Occlusion (ACO) conflicts with the need to determine the optimal timing for invasive therapy in NSTE-ACS patients. Echocardiography is an effective imaging tool for evaluating global and regional left ventricular myocardial function but the reproducibility of its mainly used conventional parameters as the ejection fraction and regional motion score is poor, reducing the accuracy of clinical application, especially in the earliest stages of ischemia. Over the past two decades, 2D Speckle Tracking Echocardiography (2D-STE) has been shown to delineate accurately, by means of the regional Longitudinal Strain (LS) measurement, the Functional Risk Area (FRA) allowing identification of high risk NSTE-ACS patients, surpassing the capabilities of traditional echocardiography and Electrocardiogram (ECG) indicators. However, the loading dependence of the LS has been shown in many studies and was overcome more recently, by regional analysis of myocardial Pressure-Strain Loop (PSL) and Myocardial Work (MW) which implemented and empowered it, demonstrating greater specificity in determining the extent and localization of the FRA during an ACS. Particularly, a regional LS with shortening less than 14% and a myocardial work below 1700 mmHg% demonstrate high sensitivity and specificity in identifying segments affected by ischemia from the earliest stages.