Tissue Doppler indices of diastolic function as prognosticator in patients without heart failure in primary care

Abstract

Background: Tissue Doppler imaging (TDI) indices of left ventricular (LV) diastolic function provide incremental prognostic information on mortality and morbidity in the general population and in several clinical scenarios. Their independent, additional role in outpatients with normal LV ejection fraction (LVEF) and without heart failure (HF) is undefined.

Methods: We reviewed clinical and echocardiographic records of 2628 consecutive outpatients 52.8% male, median age 71 years) with LVEF > 50% without concurrent or prior HF, from the Cardiovascular Center of Trieste. We analyzed septal early mitral annular velocity (e') and its combination with mitral peak early filling velocity (E/e') in relation to the composite end-point of death and cardiovascular hospitalizations.

Results: During follow-up of 26 months (interquartile range: 12-41), 392 (15%) patients experienced the endpoint (88 deaths). Increasing E/e' showed an overall association with the clinical end-point (log rank p < 0.02), but with no prognostic difference between the middle and upper tertile. Decreasing e' also showed an association with the end-point, with a more balanced stepwise risk increase for increasing tertiles (log rank p < 0.01 for all contrasts). At multivariable analysis, E/e' (either in tertiles or dichotomized according to the threshold of 15) was no longer associated with clinical outcome, whereas e' independently predicted the combined endpoint [hazard ratio 0.73 (0.53-0.94), p = 0.04]. The prognostic value of e' was incremental to that of other clinical and echocardiographic variables (p = 0.04).

Conclusions: In outpatients with normal LVEF and without HF, e' and E/e' are both associated with clinical end-points, though only e' is an independent and incremental predictor of outcome. These findings suggest a potential role for e' as a prognosticator, and spread a cautionary word about the utilization of septal E/e' alone as a surrogate for a comprehensive assessment of diastolic function in this context.

Keywords: Diastole; Echocardiography; Primary care; Prognosis; Tissue Doppler imaging.