Abstract
BACKGROUND: The diagnostic utility of transthoracic echocardiographic Doppler parameters in differentiating between normal and abnormal function of the mechanical prosthetic tricuspid valve (MPTV) has not been thoroughly investigated. This study aimed to evaluate the diagnostic accuracy and determine the optimal cutoff values of Doppler parameters in the detection of MPTV dysfunction. METHODS: We retrospectively analyzed 91 patients who underwent MPTV replacement over the past 12 years. The study cohort was divided into two groups: an experimental group consisting of 15 patients with 16 separate episodes of MPTV dysfunction, and a control group comprising 76 patients with normal leaflet function. Doppler parameters were measured at the tricuspid valve (TV) position included pressure half-time (PHT(TV)), peak early tricuspid diastolic velocity (E velocity), mean gradient (MG(TV)), velocity-time integral (VTI(TV)), effective orifice area (EOA(TV)), and the ratio of VTI(TV) to velocity-time integral of the left ventricular outflow tract (VTI ratio). Logistic regression analysis was performed to identify predictors for MPTV dysfunction, and the predictive ability of Doppler parameters was assessed using receiver operating characteristic (ROC) curve. RESULTS: Compared to the control group, patients with MPTV dysfunction exhibited significantly higher values for PHT(TV) (298.6±95.3 vs. 111.3±27.4 ms), E velocity (2.4±0.5 vs. 1.4±0.3 m/s), MG(TV) (14.5±6.0 vs. 3.2±1.5 mmHg), VTI(TV) (112.4±43.7 vs. 37.7±9.7 cm), and VTI ratio (6.2±2.8 vs. 1.9±0.6), along with a smaller EOA(TV) (0.6±0.3 vs. 1.8±0.6 cm(2)). All of these above parameters showed significant differences (P<0.001). Logistic regression and ROC curve analyses identified predictors for MPTV dysfunction: PHT(TV) >179 ms, E velocity >2.0 m/s, MG(TV) >6.9 mmHg, VTI(TV) >60 cm, VTI ratio >3.4, and EOA(TV) <1.0 cm(2). The area under the curve (AUC) for these parameters exceeded 0.95, indicating excellent diagnostic accuracy. CONCLUSIONS: The study highlights the significant diagnostic utility of transthoracic echocardiographic Doppler parameters in identifying MPTV dysfunction. A multiparameter algorithm integrating PHT(TV), E velocity, MG(TV), VTI ratio, and EOA(TV) was created to effectively distinguish between dysfunctional and normally functioning MPTVs. This algorithm provides a valuable tool for enhancing clinical decision-making and optimizing patient management. Further prospective studies are warranted to validate these findings and refine the diagnostic criteria.