Association of peak atrial longitudinal strain with right ventricular performance and short-term prognosis in patients with first acute coronary syndrome

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Myocardial infarction remains a leading cause of mortality worldwide. The abrupt elevation of left ventricular filling pressures can be backwards transmitted to the left atrium and pulmonary vascular bed leading to pulmonary oedema. Peak atrial longitudinal strain (PALS) is a sensitive surrogate marker of left atrial performance. Its association with right ventricular (RV) impairment and its prognostic role in patients with Acute Coronary Syndrome (ACS) has not been comprehensively explored. Purpose This study sought to identify the impact of PALS in RV contractile function and pulmonary artery pressures in patients presenting with first ACS and investigate its association with in-hospital mortality. Methods Three-hundred consecutive patients (N=300, STEMI=194, Non-STEMI=106) with first ACS were prospectively enrolled (mean age 61.2±11.8 years, 26% females). All patients underwent a transthoracic echocardiographic assessment within 24 hours after revascularization. The association between PALS and conventional indices of left ventricular diastolic dysfunction with RV indices was assessed using Pearson correlation coefficient. Study outcome was in-hospital mortality. Univariable and multivariable Cox Regression analysis was performed to identify outcome predictors. To construct a multivariable model, univariately significant variables (P<0.005) were selected from 3 different categories (clinical variables, laboratory indices, echocardiographic indices). Due to the limited number of events, a maximum of 4 variables were introduced in the multivariable model. To further assess the incremental advantage of PALS and Tricuspid Annular Plane Systolic Excursion/Pulmonary Artery Systolic Pressure (TAPSE/PASP) over Global Registry of Acute Coronary Event (GRACE) risk score the change in χ2 was assessed using the likelihood ratio test. Results PALS demonstrated a stronger correlation with RV contractile function and pulmonary artery pressure indices compared to mean E/e’ and E/A ratio (Table). A total of 23 (7.7%) patients died in-hospital after revascularization. In univariable Cox Regression analysis PALS was significantly associated with the outcome (HR=0.880, 95% CI=0.839–0.925, P<0.001). In the multivariable model after adjustment for GRACE risk score, LVEF, and white blood cells PALS retained independent association with the outcome (HR=0.828, 95% CI=0.698–0.983, P=0.031). A stepwise addition of PALS and RV/Pulmonary Artery coupling index (TAPSE/PASP) to GRACE risk score significantly improved the predictive value of the model (Figure). Conclusion PALS measured by transthoracic echocardiography within 24 hours of admission in patients with first ACS was a powerful predictor of in-hospital mortality. Progression of left ventricular damage to the left atrial and RV mechanics significantly worsens the risk of in-hospital mortality.