Multiparametric Approach for the Assessment of Mechanical Prosthetic Tricuspid Leaflet Function

Abstract

Background: There is a lack of comprehensive echocardiographic data to allow discrimination of normal versus abnormal mechanical prosthetic tricuspid valve (MPTV) leaflet function. The identification of such parameters is essential to optimize diagnostic and therapeutic measures. Methods: The authors investigated bileaflet MPTV function by comparing transthoracic echocardiographic data from 21 episodes of leaflet dysfunction due to valve thrombosis in 12 patients with data from 56 individuals with normal MPTV function. All episodes of dysfunction were confirmed by transesophageal echocardiography and/or cine fluoroscopy. Transthoracic echocardiography–derived two-dimensional, color, and spectral Doppler variables, including MPTV peak early diastolic velocity (E velocity), mean gradient, pressure half-time, time-velocity integral (TVI) of the MPTV, ratio of TVIMPTV to TVI of the left ventricular outflow tract (LVOT) and TVI of the right ventricular outflow tract (RVOT), and continuity-derived effective orifice area, were measured in both groups. Results: Most episodes of MPTV dysfunction resulted from simultaneous involvement of both leaflets (57%), with leaflet(s) often immobilized in the open or semiopen position (71%). Transthoracic and transesophageal echocardiography performed similarly in detecting abnormal leaflet motion (90% vs 88%, P = .68), whereas transesophageal echocardiography was better in identifying MPTV thrombosis (31% vs 14%, respectively, P = .01). Color Doppler demonstrated flow propagation abnormalities in 67% of episodes of leaflet dysfunction but not in the control group (P < .0001). Doppler variables associated with MPTV leaflet dysfunction included E velocity > 1.6 m/sec, mean gradient > 5 mm Hg, PHT > 157 msec, TVIMPTV > 42 cm, TVIMPTV/TVILVOT > 2.3, TVIMPTV/TVIRVOT > 3.0, and continuity-derived effective orifice area ≤ 1.1 cm2, with most variables showing high and similar accuracy (area under the curve ≥ 95%). Conclusions: This study represents the first comprehensive echocardiographic assessment of MPTV leaflet dysfunction that provides parameters and criteria to distinguish normal versus abnormal prosthetic valve function.