Diagnostic value of the end-systolic right atrial volume-to-strain ratio in atrial vs. ventricular secondary tricuspid regurgitation
X Zhang, C Y XingAbstract
Background
Secondary tricuspid regurgitation (STR) could be categorized into atrial (A-STR) and ventricular (V-STR) phenotypes, which are different in etiologies, presentations and outcomes. However, the current echocardiographic criteria for the differentiation of A-STR and V-STR are either purely structural or functional, and the suggested integrative framework is complex and consists of more than a dozen parameters. A simple and composite parameter is urgently needed.
Objectives
To evaluate the diagnostic performance of the right atrial volume-to-strain ratio in differentiating A-STR from V-STR.
Methods
Patients with moderate or greater STR were prospectively enrolled. All participants underwent comprehensive transthoracic echocardiographic examinations. A-STR and V-STR were defined according to the recent expert consensus suggested criteria. The performance of right heart strains and the right atrial volume-to-strain ratio for differentiation between A-STR and V-STR were assessed using receiver operating characteristic (ROC) curve analysis. Logistic regression models were further constructed to confirm parameters associated with A-STR.
Results
A total of 119 patients were enrolled, which consisted of 67 patients with A-STR and 52 with V-STR. A-STR patients demonstrated significantly larger end-systolic right atrial volume (ES RAV) (32.6 mL/m2 vs. 23.4 mL/m2, P < 0.001), lower right atrial strain (RASr) (24% vs. 36%, P < 0.001) and smaller ES right ventricular volume (ES RVV) (22.8 mL/m2 vs. 23.8 mL/m2, P = 0.006). In contrast, no significant intergroup differences were observed in right ventricular global longitudinal strain or right ventricular free wall strain. ROC analysis identified the ratio of ES RAV to RASr (ES RAV/RASr) as the strongest discriminator between A-STR and V-STR, with an AUC of 0.887 at an optimal cut-off value of 1.12. The AUCs of ES RAV, ES RVV, ES RAV/RVV and RASr were 0.780, 0.530, 0.728 and 0.865, respectively. Multivariable logistic regression analysis further confirmed ES RAV/RASr as an independent predictor for identifying A-STR (odds ratio = 9.17, P < 0.001). Multivariable diagnostic model incorporating this ratio achieved excellent discriminatory ability, with AUCs of 0.963 and 0.953, respectively.
Conclusions
The ES RAV/RASr ratio stands out as a simple and robust composite parameter for the differentiation between A-STR and V-STR.Abstract figure