A novel predictor of clinical outcomes in patients with heart failure with preserved left-ventricular ejection fraction: a pilot study

Predictors of outcomes in patients with heart failure with preserved left-ventricular ejection fraction (HFpEF) remain unclear. The ratio of early diastolic transmitral flow velocity to early diastolic myocardial velocity (E/e) has been proposed, but the predictive accuracy remains unsatisfactory. We hypothesized that E/e normalized by the stroke volume (SV), E/e/SV, could be a good predictor of outcome in HFpEF patients by reflecting the terminal slope of the end-diastolic pressure-volume relation, i.e., stiffness of the left ventricle. This pilot study was conducted to propose a novel echocardiographic index for predicting the outcomes of patients with HFpEF. Echocardiography including E/e/SV measurement was performed in consecutive 80 HFpEF patients at discharge in index hospitalization due to HF. The end points included the readmission for heart failure and cardiovascular death at 1 year after discharge. 19 patients (24%) met the end points. Receiver-operating characteristic analysis showed that E/e/SV was a strong predictive factor (AUC=0.78) compared to E/e (AUC=0.74). Kaplan-Meier analysis showed that patients with E/e/SV>0.40 had a poorer prognosis than those with E/e/SV<0.40 (p<0.01). By Cox regression multi-variate analysis, a high E/e/SV was an independent predictor of event-free survival [adjusted hazard ratio (95% CI) 14.26 (3.18, 63.93) (p=0.01)]. E/e/SV has potential to predict clinical outcomes in patients with HFpEF.