Two-Dimensional and Three-Dimensional Transthoracic Echocardiography as Predictive and Prognostic Indicators of All-Cause Mortality in Heart Failure with Reduced Ejection Fraction in Patients with Ischemic Heart Disease

BACKGROUND This study aimed to compare the predictive role of two-dimensional transthoracic echocardiography (2D-TTE) and three-dimensional transthoracic echocardiography (3D-TTE) on in-hospital all-cause mortality in patients with heart failure and reduced ejection fraction (HFrEF) due to ischemic heart disease (IHD). MATERIAL AND METHODS Patients (N-224) with HFrEF due to IHD who had a left ventricular ejection fraction (LVEF) <40% on admission when measured by 2D-TTE and 3D-TTE were studied and divided into survival and mortality groups. Baseline demographic and clinical characteristics were compared. RESULTS Compared with the survival group (n=142), patients who died during hospitalization (n=82) were more commonly older (67.3 vs. 62.6 years), female (48.8% vs. 38.7%), with diabetes mellitus (51.2% vs. 32.4%), chronic kidney disease (48.8% vs. 32.4%), intravenous inotropes (85.4% vs. 76.1%), and intravenous vasodilators (70.7% vs. 61.3%). Regression model analysis for all-cause mortality identified significant associations with age, diabetes mellitus, myocardial infarction (MI), intravenous inotropes, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and LVEF following 2D-TTE. Age, diabetes mellitus, prior MI, the use of intravenous inotropes, NT-proBNP, LVEF, and left ventricular end-diastolic volume (LVEDV) index following 3D-TTE were significantly associated with all-cause mortality. Modeling of 2D-TTE parameters showed that the concordance statistic (C-index) increased significantly after including the LVEF, from 0.72 to 0.77 and from 0.72 to 0.80, respectively. Modeling of 3D-TTE parameters showed that the C-index increased significantly after including the LVEDV index (from 0.80 to 0.76). CONCLUSIONS In patients with HFrEF due to IHD, 3D-TTE was a better predictor than 2D-TTE of in-hospital all-cause mortality.