title: Structural abnormalities of the coronary arterial wall--in addition to luminal narrowing--affect myocardial blood flow reserve.
abstract: Multislice CT provides information on coronary luminal narrowing and on the structural abnormalities of the coronary arterial wall using densitometric analysis. We sought to investigate the effects of coronary luminal narrowing, structural abnormalities of the coronary arterial wall, and cardiovascular risk factors on regional and global myocardial blood flow (MBF) reserve.
  
  
  METHODS
  We studied 68 patients (mean age ± SD, 61 ± 10 y; 41 men, 27 women) with an intermediate probability of coronary artery disease. We measured the severity of coronary stenoses and the fibroadipose, fibromuscular, and calcium components of the coronary arterial wall by 64-row multislice CT coronary angiography. We also measured regional and global MBF reserve by PET using (13)N-ammonia as a flow tracer at rest and after dipyridamole.
  
  
  RESULTS
  One or more significant coronary stenoses (≥50% luminal narrowing) was present in 32 patients (47%), and nonsignificant stenoses were present in 15 patients (22%). Regional MBF reserve was significantly different in the territories perfused by normal coronary arteries, nonsignificant coronary stenoses, and significant coronary stenoses (P < 0.001). Calcium content was higher in the coronary arteries with significant or nonsignificant stenoses (0.95% ± 1.08% and 0.73% ± 0.93%, respectively) than in those without stenoses (0.11% ± 0.38%, P < 0.001). Significant coronary stenosis (P = 0.047) and calcium content (P = 0.017) were the only independent determinants of impaired regional MBF reserve using multivariate analysis. At multiple logistic regression analysis, the Framingham risk score, an index of global cardiovascular risk burden, was the only significant determinant of global MBF reserve (P = 0.028).
  
  
  CONCLUSIONS
  Coronary stenoses and coronary calcium content independently affect regional MBF reserve. Framingham risk score is the only significant determinant of global MBF reserve.
authors.affiliation: Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Liga
authors.forename: Cecilia
authors.initials: C
authors.lastname: Marini
authors.forename: Michele
authors.initials: M
authors.lastname: Coceani
authors.forename: Elena
authors.initials: E
authors.lastname: Filidei
authors.forename: Mathis
authors.initials: M
authors.lastname: Schlueter
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Bianchi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rossi
authors.forename: Silvia
authors.initials: S
authors.lastname: Pardini
authors.forename: Piero
authors.initials: P
authors.lastname: Salvadori
authors.forename: Oberdan
authors.initials: O
authors.lastname: Parodi
authors.forename: Daniele
authors.initials: D
authors.lastname: Rovai
authors.forename: Gianmario
authors.initials: G
authors.lastname: Sambuceti
authors.forename: Paolo
authors.initials: P
authors.lastname: Marraccini
authors.forename: Danilo
authors.initials: D
authors.lastname: Neglia
mesh_terms: D003324:Coronary Artery Disease / Q000150:complications; D023921:Coronary Stenosis / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D012039:Regional Blood Flow; D012189:Retrospective Studies; D012307:Risk Factors