Tehran University of Medical Sciences The Research in Heart Yield and Translational Medicine (RHYTHM) 3115-7270 14 4 2019 10 19 171 176 EN Kahraman Cosansu Department of Cardiology, Education and Research Hospital, Sakarya University, Adapazarı, Turkey. Harun Kilic Department of Cardiology, Education and Research Hospital, Sakarya University, Adapazarı, Turkey. Ayca Turer Cabbar Department of Cardiology, Yeditepe University, Istanbul, Turkey. Erdinc Hatipsoylu Department of Cardiology, Afsin State Hospital, Kahramanmaras, Turkey. Bilgehan Karadag Department of Cardiology, Cerrahpasa Medical Faculty, Istanbul University, Istanbul, Turkey. Ramazan Akdemir Department of Cardiology, Education and Research Hospital, Sakarya University, Adapazarı, Turkey. 2018 07 24 2019 06 23 Background: The aim of this study was to investigate the ability of a new index, namely the left ventricular internal dimension at end-diastole/mitral valve E-point septal separation (LVIDd/EPSS), to predict the left ventricular (LV) systolic function and to compare its performance with that of the EPSS index and to investigate the correlation between the LVIDd/EPSS and the left ventricular ejection fraction (LVEF). Methods: The current study recruited 142 patients who presented to the Cardiology Clinic of Sakarya University Education and Research Hospital and were followed for heart failure (HF).M-mode measurements of the EPSS and the LVIDd were recorded in the parasternal long-axis view. Results: Totally, 142 HF patients with midrange ejection fraction (HFmrEF) and reduced ejection fraction (HFrEF) were enrolled in the study. There was a significantly correlation both between the EF and the EPSS and between the EF and the LVIDd/EPSS (P<0.001). In both HFmrEF and HFrEF groups, the correlation between the LVIDd/EPSS and the EF was more significant than was the correlation between the EPSS and the EF (P<0.001). The results of the linear regression analysis indicated that the LVIDd/EPSS was an independent predictor of the HFmrEF and the HFrEF (P<0.001). In the patients with EPSS≤12, there was a significant association between the EF and the LVIDd/EPSS (P<0.001) but not between the EF and the EPSS(P>0.05). The receiver operating characteristic curve analysis showed that the LVIDd/EPSS predicted advanced HF with 87% sensitivity and 72% specificity, using a cutoff value of 3.35,and it predicted the HFrEF (EF<40%) with 84% sensitivity and 81% specificity, using a cutoff value of 3.75. Conclusion: The LVIDd/EPSS may allow certain clinicians, especially beginners and emergency department physicians, to assess the LVEF when other methods are not available or questionable­. https://rhythm.tums.ac.ir/index.php/jthc/article/view/939 https://rhythm.tums.ac.ir/index.php/jthc/article/download/939/870