title: [A new methodologic approach for determining right ventricular volumes from transesophageal echocardiography].
abstract: In order to develop a concept of right ventricular volume estimation accounting for variance in positioning of the transesophageal transducer, non-linear scale transformations of suitable measurements of areas and perimeters were used in a new modeling-approach. This type of modeling supposes self-similarity of ventricular dimensions, a mathematical concept generalizing the notion of proportionality. In a study using right ventricular casts, we were able to demonstrate the geometry of right ventricles complies with these assumptions. The resulting multivariate power law volume estimators were developed by non-linear data fitting by learning-analyses based upon angiographic reference volumes and two areas derived from non-orthogonal sections using a monoplane transducer in a first series of studies, and two orthogonal areas with corresponding perimeters using a biplane device in a second series. Correction factors for systolic and diastolic volumes were applied. By prospective test-analyses angiographic and TEE-derived volumes were compared to evaluate our volume estimator and good agreement was found. Trend was evaluated by correlation amounts to r = 0.95 (n = 22) in series 1 with monoplane transducer, and r = 0.9 (n = 20) in series 2 with biplane transducer. This approach is of use in monitoring right ventricular function in cases with unsuitable transthoracical windows, e.g., in cardiac surgery postoperatively.
authors.affiliation: Klinik für Innere Medizin-Kardiologie, Deutsches Herzzentrum Berlin.
authors.forename: E
authors.initials: E
authors.lastname: Wellnhofer
authors.forename: J
authors.initials: J
authors.lastname: Krülls-Münch
authors.forename: U
authors.initials: U
authors.lastname: Sauer
authors.forename: H
authors.initials: H
authors.lastname: Oswald
authors.forename: E
authors.initials: E
authors.lastname: Fleck
mesh_terms: D000328:Adult; D000368:Aged; D002306:Cardiac Volume / Q000502:physiology*; D003198:Computer Simulation; D017548:Echocardiography, Transesophageal / Q000295:instrumentation*; D005260:Female; D006331:Heart Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D008962:Models, Theoretical; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D016278:Ventricular Function, Right / Q000502:physiology*
vernacular_title: Ein neuer methodischer Ansatz zur Bestimmung der rechtsventrikulären Volumina aus dem transösophagealen Echokardiogramm.