Coronary artery spasm
Coronary artery spasm is a condition in which an epicardial coronary artery or coronary bypass graft exhibits abnormal transient constriction with the possible or subsequent development of myocardial ischaemia. Porcine models have demonstrated the important role of atherosclerotic/inflammatory changes of the coronary artery and established that hypercontraction of vascular smooth muscle cells plays a central role in the genesis of spasm and is, in part, dependent on activation of Rho-kinase, a molecular switch for vascular smooth muscle cell contraction. Fasudil, which is used for the treatment of cerebral vasospasm in Japan, is metabolized to hydroxyfasudil and functions as a selective Rho-kinase inhibitor. Recent studies demonstrated that inflammatory changes in the adventitia of the coronary artery play an important role for Rho-kinase activation of vascular smooth muscle cells. Prevention and treatment of coronary spasm is important in preventing acute coronary syndromes and sudden cardiac death.