Relationship Between Pulmonary Venous Flow and Prosthetic Mitral Valve Thrombosis

BACKGROUND: Prosthetic valve thrombosis (PVT) may impair pulmonary venous flow (PVF) and left atrial appendage (LAA) functions. An investigation was conducted to determine the association between left superior PVF and LAA functions and mitral PVT. METHODS: This observational case-control study included 100 consecutive patients (87 females, 13 males; mean age 59 years; range 35-71 years) with mechanical mitral PVT, and 50 age- and gender-matched otherwise healthy controls with normally functioning mitral prostheses. All patients were included after comprehensive transesophageal echocardiography (TEE) examinations for the presence and quantification of PVT, the left atrial diameter, and LAA length. Peak systolic velocity (PSV), velocity-time integral of systolic flow (VTI-s), peak diastolic velocity (PDV), velocity-time integral of diastolic flow (VTI-d), systolic fraction (SFr) of the left upper PVF and the flow of the LAA orifice were each recorded using color-guided pulsed-wave Doppler imaging during TEE. RESULTS: The PSV [30 cm/s (range: 13-77 cm/s) versus 44 cm/s (range: 16-71 cm/s)], respectively (p = 0.002), VTI-s [(2.85 cm (range: 0.5-10.7 cm) versus 5 cm (range: 1.3-12.7 cm)], respectively (p <0.001), VTI-d [(3 cm (range: 0.6-9.7 cm) versus 4.2 cm (range: 1.5-8.3 cm)], respectively (p <0.001), SFr (45.5% (range: 15.66-67.44%) versus 50 % (range: 21.11-82.61%)], respectively (p = 0.008), and LAA orifice velocity [(23 cm/s (range: 11-75 cm/s) versus 34 cm/s (range: 10-112 cm/s)], respectively (p = 0.011) were each significantly lower in patients with PVT compared to controls. The PDV was similar between groups. Patients with obstructive PVT (n = 21) had a lower PDV and a higher VTI-d compared to those with non-obstructive PVT. CONCLUSIONS: Mitral mechanical PVT is associated with decreased systolic PVF and LAA function. The presence of obstructive PVT is associated with further limitations of diastolic flow velocity, and a compensatory prolongation of diastolic flow of the left upper pulmonary vein.