Accumulation of Calcium and Phosphorus in the Coronary Arteries of Thai Subjects

To clarify the manner of accumulation of Ca and P in the coronary arteries, the authors divided the coronary arteries into many segments based on arterial ramification and investigated the element contents of the segments by direct chemical analysis. After ordinary dissection at Chiang Mai University was finished, the left coronary (LC) and the right coronary (RC) arteries were removed successively from the hearts of Thai subjects. The Thai subjects consisted of seven men and five women, ranging in age from 42 to 87 years (average age = 73.9 ± 13.5 years). The LC and the RC arteries were divided into 19 segments based on arterial ramification. After incineration with nitric acid and perchloric acid, element contents of the segments were analyzed by inductively coupled plasma–atomic emission spectrometry. In two cases, a significant content of Ca and P was contained only in the left anterior descending (LAD) artery (type I). In four cases, a significant content of Ca and P was contained in both the LAD and the RC arteries (type II). In five cases, a significant content of Ca and P was contained in all the LAD, the RC, and the circumflex (CF) arteries (type III). In the other one case, no significant content of Ca and P was contained in the coronary arteries. The manner of accumulation of Ca and P in the coronary arteries was classified into the three types, I, II, and III. Regarding the average content of elements in 12 cases, the average content of Ca was the highest in the segment of the LAD artery ramifying the first left diagonal artery and was higher in the proximal and distal adjacent segments of the LAD artery ramifying the first left diagonal artery, the proximal segment of the RC artery, and the proximal segment of the CF artery. To examine an effect of arterial ramification on accumulation of Ca and P, the differences in the Ca and P content between artery-ramifying and non-ramified proximal or distal segments of the coronary arteries were analyzed with Student’s t test. It was found that there were no significant differences in the Ca and P content between the artery-ramifying and non-ramified proximal or distal segments of the coronary arteries.