Rapid Rise of Cardio-Ankle Vascular Index May Be a Trigger of Cerebro-Cardiovascular Events: Proposal of Smooth Muscle Cell Contraction Theory for Plaque Rupture

Kazuhiro Shimizu,1 Mao Takahashi,1 Shuji Sato,1 Atsuhito Saiki,1 Daiji Nagayama,1 Masashi Harada,2 Chikao Miyazaki,2 Akira Takahara,3 Kohji Shirai1 1Department of Internal Medicine, Toho University Sakura Medical Center, Sakura, Chiba, Japan; 2Department of Neurosurgery, Toho University Omori Medical Center, Omori, Tokyo, Japan; 3Department of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba, JapanCorrespondence: Kohji ShiraiDepartment of Internal Medicine, Toho University Sakura Medical Center, 561-4 Shimoshizu, Sakura City, Chiba, 285-8741, JapanTel +81-43-462-8811Fax +81-43-462-8820Email kshirai@kb3.so-net.ne.jpAbstract: Cardiovascular diseases have been recognized as the main cause of death all over the world. Recently, the established cardio-ankle vascular index (CAVI) has become known as an index of arterial stiffness of the arterial tree from the origin of the aorta to the ankle. CAVI reflects the progress of arteriosclerosis, and a rapid rise in CAVI indicates arterial smooth muscle cell contraction. Considering the vasculature of the atheroma where vasa vasorum penetrates the smooth muscle cell layer and supplies blood to the intimal atheromatous lesion, a rapid rise of CAVI means “choked” atheroma. Thus, we proposed a “smooth muscle cell contraction” hypothesis of plaque rupture.Keywords: arterial stiffness, atherosclerosis, smooth muscle cell contraction, CAVI