Valvular calcification and atherosclerosis.

1) Takeda Y, Hoshiga M, Tatsugami F, Morinaga I, Takehara K, Hotchi J, Yuki T, Ishihara T, Hanafusa T: Clinical Significance of Calcification in Ascending Aorta as a Marker for the Requirement of Coronary Revascularization. J Atheroscler Thromb, 2009 Aug 27. [Epub ahead of print] 2) Eisen A, Tenenbaum A, Koren-Morag N, Tanne D, Shemesh J, Imazio M, Fisman EZ, Motro M, Schwammenthal E, Adler Y: Calcification of the thoracic aorta as detected by spiral computed tomography among stable angina pectoris patients: association with cardiovascular events and death. Circulation, 2008; 118: 1328-1334 3) Yetkin E, Waltenberger J: Molecular and cellular mechanisms of aortic stenosis. Int J Cardiol, 2009; 135: 4-13 4) Aksoy Y, Yagmur C, Tekin GO, Yagmur J, Topal E, Kekilli E, Turhan H, Kosar F, Yetkin E: Aortic valve calcification: association with bone mineral density and cardiovascular risk factors. Coron Artery Dis, 2005; 16: 379-383 5) Yetkin E, Yagmur C, Yagmur J, Tekin GO, Kekilli E, Uckan A, Aksoy Y, Turhan H: Evaluation of cardiovascular risk factors and bone mineral density in patients undergoing coronary angiography and relation of findings to mitral annular calcium. Am J Cardiol, 2007; 99: 159-162 We have read the article published by Takeda et al.. Briefly, they analyzed vascular (coronary artery, thoracic ascending aorta) and valvular (aortic and mitral valve) calcification by multi-detector spiral computed tomography. Ultimately, they found that calcification at the sites of the ascending thoracic aorta and coronary artery is related to significant coronary stenosis >50%. Although they reported a close association between coronary artery stenosis and thoracic aortic calcification, the absence of any association between valvular calcification and coronary stenosis caught our attention. The association between thoracic aortic calcification and coronary artery calcification reflecting underlying atherosclerosis is well documented in the literature; however, the underlying mechanism of valvular calcification is still under debate. Although they have common cardiovascular risk factors, aortic valve calcification is an active process involving osteoblast-like differentiation and extracellular matrix remodeling (reviewed by Yetkin and Waltenberger). Recently, it has been reported that the rate of significant coronary artery stenosis >50% in patients with aortic valve calcification and mitral annular calcification is comparable to that without valvular calcification . We agree with the authors that traditional risk factors should be strictly managed in patients with thoracic and valvular calcification. On the other hand, we believe that the mechanism of aortic valve calcification may differ from atherosclerosis. Although there are similarities in the risk factors and the process of atherogenesis, not all patients with coronary artery disease or atherocsclerosis have calcific aortic stenosis. In this respect, the absence of an association between significant coronary artery stenosis and valvular calcification presented by Takeda et al. will encourage further studies to elucidate the controversy of the