title: Coronary artery calcium distribution and interscan measurement variability in end-stage renal and coronary heart disease patients.
abstract: BACKGROUND
  Coronary heart disease patients and end-stage renal disease patients have been documented to have an increased amount of coronary artery calcifications (CAC).
  
  
  OBJECTIVE
  To evaluate the distribution of CAC and its influence on interscan variability of measurement in end-stage renal disease and coronary heart disease patients, proven to have calcifications.
  
  
  METHODS
  69 patients having CAC, including 34 with coronary heart disease and 35 with end-stage renal disease, were scanned twice with multidetector-row computed tomography (MDCT). Amount of CAC was determined as the number of calcified lesions (CN), total calcium score (CS), calcium volume (CV), and calcium mass (CM). Distribution of CAC was evaluated on a per-patient basis as the median CS and CM of a single lesion. Density of the calcifications was calculated as the patient's CM divided by CV.
  
  
  RESULTS
  The overall median CS was 457.2, and the median CM was 75.6 mg. There were no significant differences in the number of calcified lesions, CS, or CM between the two groups. Both CS and CM of a single lesion, as well as the mean calcium density were lower in renal disease patients (P<0.05) than in coronary heart disease subjects. The relative interscan variability of coronary calcium measurement was higher in the renal disease group (P<0.05). There was a negative correlation between the calcium concentration and the relative interscan variability.
  
  
  CONCLUSIONS
  The results indicate that the coronary calcium distribution influences the measurement interscan reproducibility, and the distribution may differ between end-stage renal disease patients and coronary heart disease patients, reflecting the dissimilar nature of coronary calcifications in those groups.
authors.affiliation: Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland. serafin@mp.pl
authors.forename: Z
authors.initials: Z
authors.lastname: Serafin
authors.forename: K
authors.initials: K
authors.lastname: Laskowska
authors.forename: M
authors.initials: M
authors.lastname: Marzec
authors.forename: T A
authors.initials: TA
authors.lastname: Sinjab
authors.forename: W
authors.initials: W
authors.lastname: Lasek
authors.forename: Z
authors.initials: Z
authors.lastname: Włodarczyk
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002118:Calcium / Q000378:metabolism; D017023:Coronary Angiography / Q000706:statistics & numerical data*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000706:statistics & numerical data*; D007676:Kidney Failure, Chronic / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D012984:Software; D036542:Tomography, Spiral Computed / Q000706:statistics & numerical data*
chemical_list: D002118:Calcium