Modifiers of the Association between E/e' Ratio and Survival among Patients with No Apparent Structural or Functional Cardiac Abnormality

Abstract

BackgroundThe ratio between early mitral flow wave to early diastolic mitral annulus velocity (E/e’ ratio) varies according to age and sex and is associated with mortality in heart failure. We sought to describe the association between E/e’ and mortality in patients with no apparent structural or functional cardiac abnormality and explore possible modifiers of this association. MethodsA retrospective study of 104,315 patients who underwent echocardiographic evaluation during 2009-2021 in the largest tertiary center in Israel. Patients with cancer, ventricular dysfunction, significant valvular or structural heart disease, or evidence of pulmonary hypertension were excluded. ResultsThe final analysis included 32,836 patients with a median age of 56 (43-66) years, and 13,547 (41%) were female. The median E/e’ was 8.3 (6.8-10.3), and 9,306 (28%) had an E/e’ >10. During a median follow-up of 5.7 (3.3-8.5) years, 2,396 (7.3%) individuals died. E/e’ >10 was associated with mortality (adjusted hazard ratio [HR] 1.16, 95% confidence interval [CI] 1.07-1.27, p<0.001). The mortality risk associated with E/e’ >10 was significantly higher in those aged ≤70 (HR 1.26, 95% CI 1.12-1.42, p<0.001), males (HR 1.34, 95% CI 1.19-1.49, p<0.001), a normal left ventricular mass (HR 1.13, 95% CI 1.02-1.24, p = 0.017), and pulmonary artery pressure <30 mmHg (HR 1.18, 95% CI 1.06-1.30, p = 0.003). ConclusionAn elevated E/e’ is associated with mortality, specifically in younger individuals, males, and those with a normal left ventricular mass and lower pulmonary artery pressure. This suggests that an elevated E/e’ might be a marker of subclinical risk in these subgroups. Further studies are needed to identify whether an elevated E/e' is useful in shared decision-making regarding the management of cardiovascular risk factors.