Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Keywords: evaluation ; Germany ; imaging ; QUANTIFICATION ; SYSTEM ; SYSTEMS ; VOLUME ; NEW-YORK ; ACCURACY ; SURGERY ; validation ; FLOW ; magnetic resonance ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; VECTORS ; VECTOR ; SURFACE ; RECONSTRUCTION ; COLOR DOPPLER ; LACKING ; VOLUMES ; AORTIC REGURGITATION ; CARDIOVASCULAR-SYSTEM ; CONTROL-VOLUME METHOD ; INTEGRATION ; MITRAL REGURGITATION ; QUANTITATIVE ASSESSMENT ; resonance imaging ; respiratory system ; STANDARD ; VALVULAR REGURGITATION ; VELOCITY
    Abstract: Background. Three-dimensional assessment of regurgitant jet volume is the prerequisite for stratifying valve insufficiency. However, systematic comparison of three-dimensional methods is lacking. Therefore, we evaluated magnetic resonance imaging and three-dimensional echocardiography experimentally. Methods. An insufficiency chamber (22 x 18.5 x 27 cm; ostia 10, 16, and 20 mm; regurgitant volumes 2.3 to 25 mL) within experimental circulation (BioMedicus pump, tubes, pulsatile flow 0.2 to 1.9 L/min) was used for three-dimensional echocardiography (HP Sonos 2500) and magnetic resonance imaging (Siemens Magnetom Vision). Doppler flowmeter served as a gold standard. Segmentation used thresholding and surface integration of velocity vectors. jet volume was evaluated qualitatively by polynom fitting. Results. jet volume calculated by magnetic resonance (r = 0.99, p 〈 0.0001) and by echocardiography (r = 0.99, p 〈 0.0001) correlated identically to the gold standard. jet volume derived from imaging correlated with each other by r = 0.98 (p 〈 0.0001). Polynom fits indicated a more paraboloid shape of magnetic resonance jet volume. Conclusions. Experimentally, three-dimensional echocardiography and magnetic resonance imaging possess identical accuracy for determining regurgitant jet volume. Magnetic resonance imaging seems to provide qualitatively better image data for three-dimensional reconstruction. (C) 2004 by The Society of Thoracic Surgeons
    Type of Publication: Journal article published
    PubMed ID: 15223411
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    Keywords: Germany ; GENERATION ; SYSTEM ; TOOL ; VOLUME ; DISEASE ; SURGERY ; PATIENT ; PARAMETERS ; Jun ; MANAGEMENT ; monitoring ; cardiac surgery ; ejection fraction ; pulmonary artery catheter ; right ventricle ; thermodilution ; transesophageal 3D echocardiography ; TRANSESOPHAGEAL ECHOCARDIOGRAPHY
    Abstract: Objective: Right ventricular function is an important aspect of global cardiac performance which affects patients' outcome after cardiac surgery. Due to its geometrical complexity, the assessment of right ventricular function is still a very difficult task. Aim of this study was to investigate the value of a new technique for intraoperative assessment of right ventricle based on transesophageal 3D-echocardiography, and to compare it to volumetric thermodilution by using a new generation of fast response thermistor pulmonary artery catheters. Methods: Twenty-five patients with coronary artery disease underwent 68 intraoperative measurements by 3D-echocardiography and thermodilution simultaneously. Following parameters were analysed: right ventricular end-diastolic volume (RVEDV), end-systolic volume (RVESV) and ejection fraction (RVEF). Pulmonary, systemic and central venous pressures were simultaneously recorded. Segmentation of right ventricular volumes were obtained by the 'Coons-Patches' technique, which was implemented into the EchoAnalyzer (R), a multitask system developed at our institution for three-dimensional functional and structural measurements. Results: Right ventricular volumes obtained by 3D-echocardiography did not show significant correlations to those obtained by thermodilution. Volumetric thermodilution systematically overestimates right ventricular volumes. Significant correlations were found between RVEF measured by 3D-echocardiography and those obtained by thermodilution (r=0.93; y=0.2+0.80x; SEE=0.03; P 〈 0.01). Bland-Altmann analysis showed that thermodilution systematically underestimates RVEF. The bias for measuring RVEF was +15.6% with a precision of +/- 4.3%. The patients were divided into two groups according to left ventricular function. The group of patients with impaired function showed significantly tower right ventricular ejection fraction (44.1 +/- 4.6 vs. 55.1 +/- 3.9%; P 〈 0.01). Conclusions: Three-dimensional echocardiography provides a useful non-invasive tool for intraoperative and serial assessment of right ventricular function. This new technique, which overcomes the limitations of previous methods, may offer key insights into management and outcome of patients with severe impairment of cardiac function. (c) 2005 Elsevier B.V. All rights reserved
    Type of Publication: Journal article published
    PubMed ID: 15896606
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...