title: Factors Determining Left Main Coronary Artery Luminal Area.
abstract: BACKGROUND
  A certain minimal luminal cross-sectional area has been traditionally used in clinical practice as a cut-off value to determine severity of left main coronary artery (LMCA) stenosis. The severity of stenosis, however, depends on the baseline luminal area (ie, area prior to stenosis), which may vary among individuals. The present study was undertaken to define normal LMCA luminal area using current technology in vivo.
  
  
  METHODS
  LMCA luminal area was determined using multislice computed tomography coronary angiography. Eighty-six subjects with normal coronary arteries and calcium score of zero were included in this study. Left ventricular (LV) mass and LV volumes (systolic, diastolic) were also measured.
  
  
  RESULTS
  A wide distribution was found in LMCA luminal area, with median value 17.3 mm² and range 8.1-33.9 mm². A relationship was found between log(LMCA luminal area) and log(LV mass) (r=.515; P<.001) and with body surface area (r=.273; P=.01). Significant relationships were also found between LMCA luminal area and LV volumes (systolic, diastolic). In multiple regression analysis, however, the LV mass was the only independent predictor of LMCA luminal area.
  
  
  CONCLUSIONS
  LMCA luminal area varies substantially among individuals with normal coronary arteries and is related to many other factors. The data suggest that the current practice of using a minimal luminal area cut-off when assessing LMCA stenosis may be misleading, and thus available information should be individualized.
authors.affiliation: The Ohio State University, Department of Medicine/Cardiovascular Medicine, Columbus, Ohio 43210 USA. kdboudoulas@osumc.edu.
authors.forename: Konstantinos Dean
authors.initials: KD
authors.lastname: Boudoulas
authors.forename: Peter M
authors.initials: PM
authors.lastname: Bittenbender
authors.forename: Haikady N
authors.initials: HN
authors.lastname: Nagaraja
authors.forename: Omar
authors.initials: O
authors.lastname: Kahaly
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Dickerson
authors.forename: Subha V
authors.initials: SV
authors.lastname: Raman
authors.forename: Ernest L
authors.initials: EL
authors.lastname: Mazzaferri
authors.forename: Charles A
authors.initials: CA
authors.lastname: Bush
mesh_terms: D000328:Adult; D000072226:Computed Tomography Angiography / Q000379:methods*; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000175:diagnosis*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D061330:Multidetector Computed Tomography / Q000379:methods*; D015203:Reproducibility of Results; D012720:Severity of Illness Index