The relationship between right ventricular functions and early clinical events during hospitalization and after discharge in patients hospitalized with diagnosis of low ejection fraction heart failure

Background and Aim: It is known that the right ventricle (RV) plays an important role in the morbidity and mortality of patients with congestive heart failure, arrhythmia, ischemic heart disease, sudden cardiac death, and pulmonary hypertension. Pathological changes in the left ventricle structure and functions cause remodeling in the RV. Consequently, structure and functions of RV are deteriorated leading RV failure. Right ventricular dysfunction is an independent predictor of poor prognosis in the patients with left ventricle failure. In this study, it is aimed to investigate the relationship between RV functions and early clinical events in hospital and after discharge in patients who were followed up for heart failure with a low ejection fraction and were hospitalized with the diagnosis of heart failure. Materials and Methods: Seventy patients with a left ventricular ejection fraction below 45% who were hospitalized in the Cardiology Department in of Akdeniz University Faculty of Medicine with diagnosis of uncompensated heart failure were enrolled in this study. They were stabilized after medical treatment and discharged. Thereafter, they were followed up for 6 months in terms of clinical events. The patients over 18 years of age, with good echogenicity during echocardiographic evaluation were included to the study. The treatment and follow-up protocols of the patients were not interfered by the authors. Image windows used as standard in the 2D echocardiography technique were recorded while the related technique was being performed. Speckle tracking echocardiography method was analyzed in the software program called Q-LAB (Philips). Results: Composite adverse events were observed in 45 patients (64.3%), while composite adverse events were not observed in 25 patients (35.7%). Relation between the independent risk factors and composite adverse events were analyzed with binary logistic regression analysis. Because RV FAC, RV Global LS and RV free W Strain values are related to each other, 3 separate models have been created for these variables. There were no factors independently associated with composite termination in Model 1. In Model 2, increased NYHA (OR: 22.956; 95% CI: 1.21-435.38; p=0.037) and decreased RV Global LS values (OR: 0.66; 95% CI: 0.511-0.852; p =0.001) were found to increase the risk of combined endpoint. In Model 3, decreased RV Free W Strain (OR: 0.643; 95% CI: 0.492-0.839; p=0.001) was independently associated with composite endpoint. ROC analysis was performed to determine the distinctive performance of RV Global LS and RV Free W Strain parameters in the prediction of mortality in patients. RV Global LS (AUC=0.837 [95% CI: 0.729-0.914]; p<0.001) and RV Free W Strain (AUC=0.816 [95% CI: 0.706-0.899]; p<0.001) were determined as distinguishing factors related with mortality. The optimal cut-off value determined by Youden index was calculated for RV Global LS and was determined as ≤12.7 (Sensitivity: 100% and Selectivity: 69.09%) and for RV Free W Strain it was determined as ≤14.6 (Sensitivity: 86.67% and Selectivity: 74.55%). Conclusion: We found that RV GLS and RV fwLS are closely related. Moreover, both measurements were correlated not only with parameters reflecting RV systolic function, but also with parameters reflecting LV function. However, RV GLS and RV fwLS both had similar prognostic role in multivariate analysis. It was clearly demonstrated in our study that both parameters are better prognostic predictors than other traditional echocardiographic parameters such as TAPSE, tricuspid S', RV FAC.