Awareness of right atrial (RA)-right ventricular(RV) axes in pulmonary hypertension (PH) is growing. Vascular remodeling with concomitant increased afterload eventually induces progressive RV maldapatation with impairment of RV function. RA speckle tracking has emerged as an important tool for the assessment of RA deformation and function. However, detailed association of RV function and RA phasic performance is currently unknown.
Patients with PH from the RIGHT HEART I study (Unique identifier: NCT03403868) were included. RA reservoir function was prospectively assessed with echocardiographic speckle tracking analysis of peak longitudinal strain (PLS%). PLS% and B-type natriuretic Peptide (BNP) were measured within 24 hours of diagnostic right heart catheterization and conductance catheter with assessment of single-beat pressure-volume loops. Spearman rho correlation was used to determine the association of PLS% with RV function.
In total 51 patients (48 with pulmonary arterial hypertension, 3 with inoperable chronic thromboembolic pulmonary hypertension) of whom the majority presented in WHO functional class III were analyzed. Elevated mean pulmonary pressure [mPAP] (rho= -0.336; p= 0.0016) and RV diastolic pressure [RVEDP] (rho= -0.489; p<0.001) were significantly associated with impaired RA PLS%. RA PLS% showed significant correlation with PVR (rho= -0.313; p= 0.025) and Tau (rho= -0.421; p= 0.002). In addition, BNP was associated with RA PLS% (rho= -0.486; p<0.001).
Chronic pressure overload and increased afterload are associated with impaired RA reservoir function in PH. Strain analyses of RA reservoir function offer a novel tool to analysis impairment of the RA-RV axis.