Purpose: To evaluate the different methods for grading mitral regurgitation (MR) by transesophageal echocardiography (TEE) in patients with clinical suspicion of mitral prosthesis dysfunction.
Methods: Cardiac catheterization (Cath) was performed in 15 patients for grading the severity of prosthetic MR, divided in two groups based on the presence or absence of severe MR. Prosthetic MR was quantified by TEE using methods commonly used for MR of native valves: subjective assessment by color Doppler, objective assessment based on absolute jet area and on its relative area (jet area/left atrial area) and assessment based on the presence of systolic flow reversal in pulmonary vein.
Results: Prosthetic MR was mostly transprosthetic (14 patients) and eccentric (11 patients). There was significant correlation (p < 0.05) between Cath and TEE for identification of severe MR based on subjective assessment and on the presence of systolic flow reversal in pulmonary vein. Identification based on absolute (jet area > 7 cm2) and relative (jet area > 35% of left atrial area) jet areas did not reveal significant correlation with the angiographic grade and showed clear underestimation by TEE when the last method was used. However, there was good correlation (p < 0.05) if relative jet areas > 30% were considered as cut point.
Conclusion: TEE correctly identified angiographic severe mitral prosthesis regurgitation, mainly by the presence of systolic flow reversal in pulmonary vein and subjective assessment. The estimation of severity of the prosthetic MR by absolute or relative jet area seems to be limited and should be used with caution due to eccentricity of the regurgitant jet, frequently seen in mitral prosthesis dysfunction.