title: Cardiac function changes with switching from the supine to prone position: analysis by quantitative semiconductor gated single-photon emission computed tomography.
abstract: BACKGROUND
  Prone positioning is required in certain operations such as spinal surgery. Changes in cardiac function in the prone position have been studied with various methodologies. Few studies have investigated changes in left ventricular diastolic function and rhythm in subjects turned prone.
  
  
  RESULTS
  Cardiac function was evaluated in the supine and prone positions in 90 patients without atrial fibrillation who underwent (99m)Tc-tetrofosmin quantitative gated single-photon emission computed tomography. Three groups of 30 patients each were classified as "no history of myocardial ischemia or cardiomyopathy" (Group A), "history of myocardial infarction" (Group B), and "ischemic heart disease without myocardial infarction history" (Group C). Upon assuming the prone position, the cardiac index and any dyssynchrony worsened in all groups. Ejection fraction changes occurred only in Group B, and diastolic function changes occurred in Groups B and C, but not in Group A. The changes caused by prone positioning were more severe in the patients with poor cardiac function.
  
  
  CONCLUSIONS
  Prone positioning induces significant changes in systolic and diastolic function, as well as dyssynchrony. The negative effects of prone positioning are more severe in patients with poor baseline cardiac function.
authors.affiliation: Department of Cardiology, Yokohama Minami Kyosai Hospital, Yokohama, Japan, mst-smz@my.email.ne.jp.
authors.forename: Masato
authors.initials: M
authors.lastname: Shimizu
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Fujii
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Yamawake
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Nishizaki
mesh_terms: D000368:Aged; D016477:Artifacts; D055426:Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D056888:Patient Positioning / Q000379:methods*; D016684:Prone Position; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012666:Semiconductors; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D016683:Supine Position; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging*
chemical_list: D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin