title: Predominant location of coronary artery atherosclerosis in the left anterior descending artery. The impact of septal perforators and the myocardial bridging effect.
abstract: BACKGROUND
  Coronary artery atherosclerosis presents characteristic patterns of plaque distribution despite systemic exposure to risk factors. We hypothesized that local hemodynamic forces induced by the systolic compression of intramuscular septal perforators could be involved in atherosclerotic processes in the left anterior descending artery (LAD) adjacent to the septal perforators' origin. Therefore we studied the spatial distribution of atherosclerosis in coronary arteries, especially in relation to the septal perforators' origin.
  
  
  METHODS
  64-slice computed tomography angiography was performed in 309 consecutive patients (92 male and 217 female) with a mean age of 59.9 years. Spatial plaque distribution in the LAD was analyzed in relation to the septal perforators' origin. Additionally, plaque distribution throughout the coronary artery tree is discussed.
  
  
  RESULTS
  The coronary calcium score (CCS) was positive in 164 patients (53.1%). In subjects with a CCS > 0, calcifications were more frequent in the LAD (n = 150, 91.5%) compared with the right coronary artery (RCA) (n = 94, 57.3%), circumflex branch (CX) (n = 76, 46.3%) or the left main stem (n = 42, 25.6%) (p < 0.001). Total CCS was higher in the LAD at 46.1 (IQR: 104.2) and RCA at 34.1 (IQR: 90.7) than in the CX at 16.8 (IQR: 61.3) (p = 0.007). In patients with calcifications restricted to a single vessel (n = 54), the most frequently affected artery was the LAD (n = 42, 77.8%). In patients with lesions limited to the LAD, the plaque was located mostly (n = 37, 88.1%) adjacent to the septal perforators' origin.
  
  
  CONCLUSIONS
  We demonstrated that coronary calcifications are most frequently located in the LAD in proximity to the septal branch origin. A possible explanation for this phenomenon could be the dynamic compression of the tunneled septal branches, which may result in disturbed blood flow in the adjacent LAD segment (milking effect).
authors: Third Department of Cardiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Silesian Center for Heart Diseases, Poland.
authors: Jarosław
authors: J
authors: Wasilewski
authors: Third Department of Cardiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Silesian Center for Heart Diseases, Poland.
authors: Jacek
authors: J
authors: Niedziela
authors: Third Department of Cardiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Silesian Center for Heart Diseases, Poland.
authors: Tadeusz
authors: T
authors: Osadnik
authors: Third Department of Cardiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Silesian Center for Heart Diseases, Poland.
authors: Agata
authors: A
authors: Duszańska
authors: Department of Radiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Poland.
authors: Wojciech
authors: W
authors: Sraga
authors: Third Department of Cardiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Silesian Center for Heart Diseases, Poland.
authors: Piotr
authors: P
authors: Desperak
authors: Department of Radiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Poland.
authors: Jolanta
authors: J
authors: Myga-Porosiło
authors: Department of Radiology, Medical University of Silesia in Katowice, School of Medicine with Division of Dentistry in Zabrze, Poland.
authors: Zuzanna
authors: Z
authors: Jackowska
authors: Department of Mechanical Engineering, University of Sheffield, England.
authors: Andrzej
authors: A
authors: Nowakowski
authors: Department of Diagnostic Imaging, Medical University of Silesia, Silesian Center for Heart Diseases in Zabrze, Poland.
authors: Jan
authors: J
authors: Głowacki
keywords: atherosclerosis; computed tomography angiography; coronary arteries