Cardiovascular calcification: an inflammatory disease.

Cardiovascular calcification is an independent risk factor for cardiovascular morbidity and mortality. This disease of dysregulated metabolism is no longer viewed as a passive degenerative disease, but instead as an active process triggered by pro-inflammatory cues. Furthermore, a positive feedback loop of calcification and inflammation is hypothesized to drive disease progression in arterial calcification. Both calcific aortic valve disease and atherosclerotic arterial calcification may possess similar underlying mechanisms. Early histopathological studies first highlighted the contribution of inflammation to cardiovascular calcification by demonstrating the accumulation of macrophages and T lymphocytes in `early' lesions within the aortic valves and arteries. A series of in vitro work followed, which gave a mechanistic insight into the stimulation of smooth muscle cells to undergo osteogenic differentiation and mineralization. The emergence of novel technology, in the form of animal models and more recently molecular imaging, has enabled accelerated progression of this field, by providing strong evidence regarding the concept of this disorder as an inflammatory disease. Although there are still gaps in our knowledge of the mechanisms behind this disorder, this review discusses the various studies that have helped form the concept of the inflammation-dependent cardiovascular calcification paradigm.