Characteristics and Significance of Tricuspid Valve Prolapse in a Large Multidecade Echocardiographic Study.

BACKGROUND: Characteristics of tricuspid valve prolapse (TVP) on transthoracic echocardiography are not well defined. As tricuspid valve interventions are increasingly considered, information on the definition and clinical significance of TVP is needed. METHODS: At the authors' institution, between January 26, 2000, and September 20, 2018, 410 patients (0.3%) were determined to have suspected TVP. These transthoracic echocardiograms and those of 97 age- and sex-matched normal control subjects were reviewed. Interrater agreement on TVP by visual inspection was assessed in a blinded subset. Leaflet atrial displacement (AD) > 2 SDs above the mean in normal control subjects was used to identify an empiric definition of TVP Features of patients meeting this definition were evaluated. RESULTS: Three hundred twelve transthoracic echocardiograms with available and interpretable images (76.1%) were included. Interrater agreement on TVP diagnosis by visual inspection was moderate. Normal values of AD were up to 4 mm in the right ventricular inflow view and 2 mm in all other views. AD > 2 mm in the parasternal short-axis view had the best accuracy against suspected TVP to identify TVP. Those with TVP by this definition more frequently had 3 to 4+ tricuspid regurgitation (22.2% vs 3.1%; P < .001), mitral valve prolapse (MVP; 75.0% vs 3.1%; P < .001), and more clinically significant MVP (greater prevalence of 3 to 4+ mitral regurgitation). No difference in mortality was observed in those with isolated TVP versus TVP and MVP (log-rank P = .93). CONCLUSIONS: In the largest study of TVP to date, interrater agreement on TVP diagnosis by visual inspection was moderate. A cutoff of >2-mm AD in the parasternal short-axis view was optimal to define TVP. Those with TVP by this definition had more significant tricuspid regurgitation, larger right ventricles, and more clinically significant MVP. Overall, these results suggest an increased role for surveillance for TVP and the need for clear diagnostic criteria in updated guidelines.