Abstract 18509: Right Atrial Reservoir and Booster Strain Correlate Better Than Right Atrial Area with Tricuspid Annular Plane Systolic Excursion

Abstract

Background: Mechanical and volumetric dynamics and the mutual interdependence of right sided cardiac structures (right ventricle, RV: right atrium, RA) have not been adequately studied in routine clinical practice.

Methods: 36 human subjects (56 ±10 years) referred for routine echocardiography for various clinical indications were included in the study. The echo-Doppler measurements included E/E, RV systolic pressure (pulmonary artery systolic pressure PASP), left ventricular ejection fraction LVEF%, TAPSE (tricuspid annular plane systolic excursion), RA area, RA active emptying fraction (RA AEF %), RA expansion index (RA EI), and, RA passive emptying fraction ( RA PEF%). Speckle tracking echocardiography was used to obtain RA booster, RA reservoir, and RA conduit strain (Fig) as well as RV basal, mid and apical strain.

Results: LVEF, TAPSE, E/E, PASP, RA area were 60±8%, 23± 4 mm , 8±3, 29± 9mmHg, and 16±3 cm2 respectively. RA active emptying fraction (RA AEF %;) was 43 ±16%. RA booster, reservoir, and conduit strain respectively were -16± 3%, 33± 10%, and 15 ±7%. RV basal, mid, and apical strain were -23± 8%, -24± 6%, and -22± 7% respectively. Multiple regression analysis showed strongest correlation between TAPSE and RA AEF% (r= 0.48; p= 0.001) and between TAPSE and RA reservoir strain (r= 0.45; p= 0.001) while RA AEF and RA booster strain also correlated significantly ( r= 0.39; p = 0.01). Mid RV strain correlated with TAPSE ( r= 0.40; p= 0.005). RA area, RA expansion index showed no correlation on either RV or RA volumes or mechanics.

Conclusion: In a group of patients with well-preserved LV and RV function and pressures, RA booster and reservoir strain predicted RV systolic function as measured by TAPSE. RA AEF% and mid RV S% significantly impacted tricuspid annular plane systolic excursion. RA area alone did not correlated with surrogate measures of right ventricular systolic function.