Assesment of segmental distribution of calcium scoring through coronary arteries by 16 slice computerized tomography

Background and objective: Calcification of the arterial wall is a component of atherosclerosis, and is not observed in healthy arterial wall. Accumulation of calcium in coronary arteries is well known to be related with atherosclerosis. Calcium amount in the coronary arteries is significantly related with plaque volume. Previous studies with electron beam computerized tomography (EBT) have shown that coronary artery calcium is related with further risk of coronary artery disease formation. Thus EBT is accepted as gold standard to detect calcium on coronary arterial wall. Agatston score is the most widely used method to determine the amount of coronary artery calcium. In addition, although not used frequently, volume score and calcium mass evaluation are alternative superior methods. The evolution of imaging technology has made multislice computed tomography (MSCT) more popular in the evaluation of coronary artery anatomy, which has provided better temporal resolution than the previous single slice computed tomography. In the assessment of calcium score the total amount of calcium accumulation in the coronary arteries is considered. There is insufficient evidence about the relationship between cardiac risk and the amount of calcium accumulation in any coronary segment or frequency of calcified coronary segment or localization of calcium in the coronary artery segments. The aim of our study is to investigate the distribution of coronary artery calcium accumulation and the impact of demographical data on segmental calcium score by using multislice computed tomography.Methods: 304 patients with an age range between 19 and 84 (mean 59.08 ± 10.7 years) were included in the study. 195 (64.1%) were male, 109 (35.9%) were female. Calcium scoring was performed to all patients with MSCT. Patients with calcium score of 1 or higher were enrolled. Calcium score and lesion number were assessed on a 14 segment coronary artery map.Results: Within all the segments the largest calcium deposition is found on proximal segment of left anterior descending artery (LAD). Then followed by proximal segment of right coronary artery (RCA), middle segment of LAD, middle segment of RCA, left main coronary artery (LMCA) and proximal segment of circumflex artery (CxA), respectively. The statistical difference between proximal segment of RCA and middle segment of LAD is not significant, all the others were significant. When every coronary artery is evaluated as a whole, the largest calcium deposition is found on LAD, and then followed by RCA, CxA and LMCA respectively. As segments are classified to proximal, middle and distal, the largest calcium deposition was found on proximal group than followed by middle and distal group, respectively.Conclusion: We make a segmental analysis of coronary arteries and show the maximal calcium score in the proximal segments, in addition to this we show that among the proximal segments the maximum calcium score is on the LAD proximal segment. LAD proximal segment is mostly effected segment on the coronary artery disease, as the previous studies suggested. Also previous studies have shown that coronary artery calcification is increased with coronary artery risk factors such as age, hyperlipidemia and hypertension. In our study, the calcium distribution of coronary artery calcium is correlated with these findings. Additionally, we show that, the calcium score of RCA is the only independent variable that affects the LMCA calcium score, in our study.