Left atrial stiffness index estimated by echocardiography is an independent predictor of mortality in non-ischemic dilated cardiomyopathy

Left atrial function parameters have been shown to be important prognostic markers in different clinical settings. Our objective was to evaluate the prognostic role of a non-invasive estimation of left atrial stiffness index using echocardiography in patients with non-ischemic dilated cardiomyopathy (NIDCM).

Prospective cohort study of patients with NIDCM evaluated at a tertiary Spanish hospital between 2017 and 2022. Clinical and cardiac imaging variables were collected in a multipurpose registry, and the incidence of clinical events was recorded during follow-up. Left atrial stiffness index was estimated non-invasively as the ratio between E/e' and left atrial strain in the reservoir phase.

Mean age of patients in our cohort (n=200) was 61 (14) years, and 68 (34%) were women. During a mean follow-up of 3.6 years, 33 (16.5%) patients died, and 54 (27%) were hospitalized for heart failure.

Mean left ventricular ejection fraction (LVEF) was 31% (9.5), and mean left atrial stiffness index was 1.3 (0.9), with significant differences between patients with and without events (1.68 (1.1) vs 1.21 (0.8); p=0.005) (Figure).

In a logistic regression analysis, the variables significantly associated with all-cause mortality during follow-up were LVEF, E/e' ratio, and left atrial stiffness index (Table). In a multivariable analysis, left atrial stiffness index emerged as an independent predictor of mortality (OR 1.79, 95% CI 1.19-2.69; p=0.005).

In our cohort of patients with NIDCM, the left atrial stiffness index, which combines information related to filling pressures with left atrial function, was an independent predictor of mortality and could be useful as an additional tool for risk stratification in this setting.

Differences in LA stiffness index