Prognostic Value of Right Ventricular Circumferential Strain in Patients Undergoing Isolated Tricuspid Valve Surgery

BACKGROUND: Right ventricular (RV) function is closely associated with prognosis in isolated tricuspid regurgitation. Beyond conventional longitudinal indexes, nonlongitudinal RV deformation may provide additional prognostic information. OBJECTIVES: The authors aimed to evaluate whether 3-dimensional (3D) RV circumferential strain (RV-CS) provides incremental prognostic value in patients undergoing isolated tricuspid valve surgery (ITVS). METHODS: Patients scheduled for ITVS were prospectively enrolled and underwent 3D echocardiography 1 day before surgery. 3D RV longitudinal strain, CS, and area strain were derived using commercially available software. The primary endpoint was a composite of all-cause mortality or heart failure hospitalization. RESULTS: From April 2018 to December 2024, 251 patients were enrolled; 171/251 (68.1%) were women, and the mean age was 57 ± 14 years. During a median follow-up of 495 days, 48/251 patients (19.1%) reached the primary endpoint. Baseline 3D right ventricular circumferential strain (3D RV-CS) was lower in patients with events than in those without events (P < 0.001) and showed modest but had the highest Harrell's C-index for adverse events discrimination (0.695; 95% CI: 0.618-0.774; P < 0.001) among all tested RV function parameters. Patients with impaired 3D RV-CS, defined as |3D RV-CS| < 14%, had lower 1-year event-free survival than those with preserved 3D RV-CS (54.2% vs 92.5%; log-rank P < 0.001). After multivariable adjustment, impaired 3D RV-CS remained independently associated with adverse events. Adding 3D RV-CS improved risk reclassification beyond European System for Cardiac Operative Risk Evaluation II, TRI-SCORE, and Society of Thoracic Surgeons score models. CONCLUSIONS: 3D RV-CS provides complementary prognostic information in patients undergoing ITVS and may improve preoperative risk stratification.