The relationship between tricuspid regurgitation severity and right atrial mechanics: a speckle tracking echocardiography study

The aim at this study was to assess the influence of the tricuspid regurgitation volume (TRvol) in right atrium (RA) reservoir phase myocardial mechanics. We included 55 heart failure (HF) patients referred for transthoracic echocardiography during a 2-month period. 18 Had HF with a reduced ejection fraction (HFREF) and 37 HF with a preserved ejection fraction (HFPEF). TR was chronic and functional. TRvol was calculated according to the PISA method. This study of RA used 2D-speckle tracking echocardiography to measure strain (rε_R) and strain rate (rSR_R). The reference frame coincided with the onset of the QRS. RA stiffness was assessed as the ratio: (rE/e′)/rε_R. The median age of the sample was 78 (64–84) years, with female gender predominance (63.6 %). The median value of rε_R was 16 % (range, 12.7–24.0) and of rSR_R was 1.57 s⁻¹ (range, 1.09–2.05). We observed a significant negative correlation between rε_R (r = −0.68, p < 0.01) and rSR_R (r = −0.58, p < 0.01) and TRvol. RA mechanics decreased significantly with an increase in the TR grade. We created two multivariate linear regression models for rε_R and rSR_R, separately for the patients with sinus rhythm or atrial fibrillation. The TRvol was independently associated with rε_R after adjusting to the RA area, right ventricular longitudinal systolic function and the estimated pulmonary vascular resistance. We demonstrated an increase in RA stiffness with an increase in TR severity, and an association for functional status (NYHA class) and RA compliance. The HFREF group had a significantly lower rε_R and rSR_R that the HFPEF patients. According to our study, in HF patients, a chronic volume overload state significantly reduced the RA reservoir phase mechanics.