title: Intraoperative assessment of right ventricular volume and function.
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, 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 lower 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.
authors.affiliation: Department of Cardiac Surgery, University of Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg, Germany. r.de.simone@urz.uni-heidelberg.de
authors.forename: Raffaele
authors.initials: R
authors.lastname: De Simone
authors.forename: Ivo
authors.initials: I
authors.lastname: Wolf
authors.forename: Sibylle
authors.initials: S
authors.lastname: Mottl-Link
authors.forename: Bernd W
authors.initials: BW
authors.lastname: Böttiger
authors.forename: Helmuth
authors.initials: H
authors.lastname: Rauch
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Meinzer
authors.forename: Siegfried
authors.initials: S
authors.lastname: Hagl
mesh_terms: D000368:Aged; D002306:Cardiac Volume; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D019560:Echocardiography, Three-Dimensional; D017548:Echocardiography, Transesophageal; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D013223:Statistics as Topic; D013318:Stroke Volume; D013815:Thermodilution; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000503:physiopathology; D016278:Ventricular Function, Right / Q000502:physiology*