title: Effect of lateral body position on transesophageal echocardiography images and the association with patient characteristics: A prospective observational study.
abstract: BACKGROUND
  Changes in heart position are occasionally observed on the transesophageal echocardiography (TEE) image screen after changing the body position from supine to lateral, although the magnitude of change in cardiac position varies individually. We hypothesized that this variation is associated with certain patient characteristics and evaluated how lateral positioning affects visualization of the heart on TEE and whether the magnitude of change in the heart position correlates with patient characteristics.
  
  
  METHODS
  Fifty-three lung resection patients were enrolled. Two angle and two length parameters (DqTV , DqAP , DL TV , and DL AP ) were defined to describe location change of the lateral tricuspid annulus and right ventricular apex on the TEE image between supine and lateral position. The correlation coefficients were calculated between these four parameters and patient characteristics, including age, body mass index (BMI), epicardial fat thickness, and pulmonary function variables.
  
  
  RESULTS
  The DqTV correlated positively and inversely with BMI in both right and left lateral patients (right: r = 0.6365, P = 0.0034; left: r = -0.6616, P < 0.0001, respectively). In left lateral patients, the DqTV correlated inversely with epicardial fat thickness (r = -0.4879, P = 0.0182), and the DL AP correlated positively with the forced vital capacity percent predicted (r = 0.5736, P = 0.0082).
  
  
  CONCLUSIONS
  Lateral body positioning affects cardiac visualization on TEE, and the BMI, epicardial fat thickness, and pulmonary function moderate this effect.
authors.affiliation: Department of Anesthesiology, Saitama Cardiovascular and Respiratory Center, 1696 Itai, Kumagaya 360-0105, Saitama, Japan.
authors.forename: Norikatsu
authors.initials: N
authors.lastname: Mita
authors.forename: Masataka
authors.initials: M
authors.lastname: Kuroda
authors.forename: Shigeru
authors.initials: S
authors.lastname: Saito
authors.forename: Sohtaro
authors.initials: S
authors.lastname: Miyoshi
mesh_terms: D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D017548:Echocardiography, Transesophageal / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D056888:Patient Positioning / Q000706:statistics & numerical data*; D011187:Posture; D011446:Prospective Studies; D012129:Respiratory Function Tests / Q000706:statistics & numerical data