Right atrial strain: what does it tell us about cardiac function and prognosis?

Type of funding sources: Foundation. Main funding source(s): New Zealand National Heart Foundation

The role of speckle tracking echocardiography has been expanding thanks to its utility in detecting subtle changes in cardiac function, and has prognostic value(1). Right atrial (RA) strain has shown promise in prognostication amongst patients with pulmonary hypertension and heart failure. It is associated with RA size, RV function and IVC size. However, its clinical utility and application remain under investigation (2–5).

We sought to evaluate the associations of right atrial strain with both invasive and non-invasive measure of RV function and the association of RA strain with heart failure hospitalisations and death across a heterogeneous cohort.

A single-centre retrospective analysis of data from 225 consecutive patients (age 72 ±11.6 years old; male 56%) with both right heart catheterization (RHC) and TTE. Data regarding unplanned heart failure hospitalisations and date of death were recorded. Statistical analysis was performed using SAS 15.1 to assess the association between right atrial strain and prespecified echo and haemodynamic measures of right and left heart function and prognosis defined by heart failure hospitalisations and death.

Over a median follow up of 28±16 months, there were 59 events. RA strain was associated with the following non-invasive and invasive measures of right heart function and left heart systolic function : TAPSE; RA size, RA pressure, RV strain, PAPi, RVSWI, RV FAC, LAVi, RV PA coupling (TAPSE/systolic PAP), LVEF, cardiac index, diastolic function (E/e’) with a p value of <0.05. Increasing atrial size was associated with lower values of R strain. Despite the association of impaired RV strain with prognosis, HR 2.94 (1.14 – 7.60), RA strain did not appear to be associated independently with prognosis HR 0.98 (0.95–1.0) P value = 0.0676.

Right atrial strain is independently associated with both invasive and non-invasive measures of RV function and may be a useful tool to help us assess right heart function. It did not appear to be associated with prognosis despite being independently linked with RV strain, which was strongly associated with prognosis in our cohort.