Significant disagreement between conventional parameters and 3D echocardiography-derived ejection fraction in the detection of right ventricular systolic dysfunction and its association with outcomes.

AIMS: Conventional echocardiographic parameters such as tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and free-wall longitudinal strain (FWLS) offer limited insights into the complexity of right ventricular (RV) systolic function, while 3D echocardiography-derived RV ejection fraction (RVEF) enables a comprehensive assessment. We investigated the discordance between TAPSE, FAC, FWLS, and RVEF in RV systolic function grading and associated outcomes.

METHODS: We analyzed 2D and 3D echocardiography data from two centers including 750 patients followed up for all-cause mortality. RV dysfunction was defined as RVEF<45%, with guideline-recommended thresholds (TAPSE<17 mm, FAC<35%, FWLS>-20%) considered.

RESULTS: Among patients with normal RVEF, significant proportions exhibited impaired TAPSE (21%), FAC (33%), or FWLS (8%). Conversely, numerous patients with reduced RVEF had normal TAPSE (46%), FAC (26%), or FWLS (41%). Using ROC analysis FWLS exhibited the highest AUC of discrimination for RV dysfunction (RVEF<45%) with 59% sensitivity and 92% specificity. Over a median 3.7-year follow-up, 15% of patients died. Univariable Cox regression identified TAPSE, FAC, FWLS, and RVEF as significant mortality predictors. Combining impaired conventional parameters showed that outcomes are the worst if at least two parameters are impaired and gradually better if only one or none of them (log-rank p<0.005).

CONCLUSION: Guideline-recommended cut-off values of conventional echocardiographic parameters of RV systolic function are only modestly associated with RVEF-based assessment. Impaired values of FWLS showed the closest association with the RVEF cut-off. Our results emphasize a multiparametric approach in the assessment of RV function, especially, if 3D echocardiography is not available.