Right ventricular global longitudinal strain and short-term prognosis in patients with first acute coronary syndrome

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Right ventricular (RV) dysfunction is recognized as an adverse prognostic feature in patients with Acute Coronary Syndromes (ACS). However, conventional echocardiographic indices for the evaluation of RV function have considerable limitations. Right Ventricular Global Longitudinal Strain (RV GLS) is a novel speckle-tracking echocardiographic index that assesses the overall intramyocardial function of the RV free wall and interventricular septum. Purpose The present study aimed to investigate the short-term prognostic value of RV GLS in patients with first ACS. Methods A total of 300 consecutive patients with first ACS (mean age 61.2±11.8 years, 74% males) were prospectively studied. A comprehensive transthoracic echocardiographic assessment was undertaken within 24 hours after revascularization and in-hospital mortality was assessed. Multiple multivariable Cox Regression analysis models were constructed to compare the predictive value of RV function indices for in-hospital mortality. Only significant variables (P<0.05) in the univariate analysis were included in the models. Due to the limited number of events, all multivariable models were constructed including a maximum of 3 variables. To further assess the prognostic value of RV GLS over a baseline model the change in χ2 was assessed using the likelihood ratio test. The absolute value of strain parameters was used for all analysis. Results Patients with anterior-STEMI had significantly more impaired RV GLS (anterior-STEMI 14.52±5.23 vs. inferior-STEMI 17.41±5.06 vs. lateral-STEMI 19.50±4.17 vs. Non-STEMI 20.61±3.69%, P<0.001). A total of 23 (7.7%) patients died in-hospital after revascularization. In univariate analysis RV GLS was significantly associated with in-hospital mortality (HR=0.717, 95% CI=0.642–0.801, P<0.001). After adjustment for Global Registry of Acute Coronary Event (GRACE) risk score and Left Ventricular Ejection Fraction (LVEF), RV function indices that retained independent association with in-hospital mortality were RV GLS, Fractional Area Change, and Tricuspid Annular Plane Systolic Excursion (Table). The model that included RV GLS demonstrated the highest overall χ2 value (Table). To prove the incremental value of RV GLS on in-hospital mortality prognosis, a baseline model including the GRACE risk score was created, and then LVEF was added. The further addition of RV GLS significantly increased the prognostic value the model (Figure). Conclusions RV GLS measured by transthoracic echocardiography within 24 hours after revascularization in patients with first ACS showed the strongest association with in-hospital mortality outperforming other RV function indices. RV GLS provides additine prognostic information over GRACE risk score and LVEF to predict in-hospital mortality.