Clinical Relevance of Spectral Tissue Doppler-Derived E/E' in the Diagnosis of Heart Failure with Preserved Ejection Fraction: Reply

We first would like to thank Dr Stephane Arques for his comment and point of view. The clinical value of the E/e' ratio in the diagnosis of heart failure with preserved ejection fraction is a hot topic with believers and non-believers. Actually, the problem of a reliable non-invasive assessment of left ventricular (LV) filling pressure is far to be solved and remains an object of debate and a field for future research. The aim of our editorial was to avoid simplification and underline the need for a more comprehensive approach to the echocardiographic assessment of LV filling pressure.1 Although E/e' has a relevant role in the diagnosis of heart failure with preserved ejection fraction, particularly because of its diagnostic and prognostic value,2, 3 the question is to make clear that this parameter should not be used by its own, but integrated in a multi-parametric approach, perhaps a score.4, 5 This is the reason why we think that there is no definite and objective reason to prioritize the E/e' ratio over e' velocity or the forgotten but extremely valuable assessment of the pulmonary vein flows.6-8 By the way, this is the sense of the recent recommendations which support the use of a multi-parametric approach including the assessment of E/e', septal or lateral e' velocity, maximal tricuspid regurgitation velocity, and left atrial volume for the non-invasive estimation of LV filling pressure. Moreover, we would like to underscore the importance of other echocardiographic methods, which have shown to be useful for the assessment of LV filling pressure. For instance, an increasing amount of evidence seems to support that pulmonary B-lines could perform equally or better than E/e' for predicting elevated filling pressure.9 Similarly, the diastolic stress test—even if not extensively validated—seems very useful in clinical routine,4 particularly in patients with dyspnoea on exertion and a doubtful rest echocardiography. Actually, the problem of the reliable non-invasive assessment of LV filling pressure is far to be solved and remains an object of debate and a field for future research.10 Our key message is that E/e' should not be considered the main player in the complex field of diastology.