title: Anatomical Regurgitant Orifice Detection and Quantification from 3-D Echocardiographic Images.
abstract: The vena contracta and effective regurgitant orifice area (EROA) are currently used for the clinical assessment of mitral regurgitation (MR) from 2-D color Doppler imaging. In addition to being highly user dependent and having low repeatability, these methods do not represent accurately the anatomic regurgitant orifice (ARO), which affects the adequate assessment of MR patients. We propose a novel method for semi-automatic detection and quantitative assessment of the 3-D ARO shape from 3-D transesophageal echocardiographic images. The algorithm was tested on a set of 25 patients with MR, and compared with EROA for validation. Results indicate the robustness of the proposed approach, with low variability in relation to different settings of user-defined segmentation parameters. Although EROA and ARO exhibited a good correlation (r = 0.8), relatively large biases were measured, indicating that EROA probably underestimates the real shape and size of the regurgitant orifice. Along with the higher reproducibility of the proposed approach, this highlights the limitations of current clinical approaches and underlines the importance of accurate assessment of the ARO shape for diagnosis and treatment in MR patients.
authors.affiliation: Faculty of Engineering, Universidad de San Buenaventura Bogotá, Bogotá, Colombia; Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy. Electronic address: msotaquira@usbbog.edu.co.
authors.forename: Miguel
authors.initials: M
authors.lastname: Sotaquirá
authors.affiliation: Centro Cardiologico Monzino IRCCS, Milan, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Pepi
authors.affiliation: Centro Cardiologico Monzino IRCCS, Milan, Italy.
authors.forename: Gloria
authors.initials: G
authors.lastname: Tamborini
authors.affiliation: Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milan, Italy.
authors.forename: Enrico G
authors.initials: EG
authors.lastname: Caiani
mesh_terms: D000465:Algorithms; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D017548:Echocardiography, Transesophageal / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012720:Severity of Illness Index
keywords: Anatomical regurgitant orifice; Max-flow; Min-cut; Mitral regurgitation; Region competition; Three-dimensional echocardiography