oronary spasm provokes the myocardial ischemia associated with angina pectoris, acute myocardial infarction and sudden death. 1,2 Calcium channel antagonists, nitrates or a combination of both drugs have been used effectively to prevent coronary spasm. [3][4][5][6] Indeed, the overall cardiac mortality is relatively low and the prognosis seems to be good for medically treated patients with coronary spasm. [7][8][9] Coronary spasm frequently occurs in minimally narrowed coronary segments, 10,11 suggesting a pathophysiologic correlation between coronary spasm and atherosclerosis, which has been demonstrated in an experimental animal model. 12 Several studies have examined the relationship between the clinical characteristics and prognosis of this type of angina, and demonstrated that preexistCirculation Journal Vol.67, December 2003 ing atherosclerosis could be an important risk factor for cardiac death and myocardial infarction during the relatively early phase. 5-9 However, there is little information regarding the long-term prognosis of medically treated coronary spasm with or without atherosclerotic risks, such as underlying coronary artery stenosis (CAS) and intrinsic hyperlipidemia. Such data should be important for not only preventing vasospasm, but also preventing the development of atherosclerosis. The purpose of this study was, first, to determine the event-free survival rate in patients with angiographically documented coronary spasm, and second, to identify the clinical predictors of cardiac events, particularly in patients with and without significant CAS.
Methods
Patient PopulationOf 2,740 patients who underwent diagnostic coronary angiography for suspected ischemic heart disease between 1977 and 1987, 284 consecutive patients with coronary spasm were enrolled and followed. During the follow-up, 21 patients went missing. Patient enrollment was completed in 1987 when 3-hydroxy-3-methyleglutaryl coenzyme A (HMG-CoA) reductase inhibitor, which might have altered the long-term prognosis, 13 was not generally available. Therefore, no patient had been given HMG-CoA reductase Although patients with medically treated vasospastic angina have a good outcome, few data exist regarding the role of underlying lesion severity associated with or without hyperlipidemia in the prognosis. Therefore, the aim of the present study was to assess the relationship between the long-term outcome of vasospastic angina and the factors influencing its prognosis. A total of 256 patients (219 men, 37 women; mean age, 54.1±9.2) who had coronary spasm with or without underlying lesions and were being treated with calcium channel antagonists were enrolled and followed for 13.6±3.7 years. Cardiac events consisted of cardiac death and ischemic events, which included acute myocardial infarction and unstable angina. Cox analysis selected coronary artery stenosis (CAS, ≥50%) and risk factors such as age, hypertension, diabetes mellitus, low-density lipoprotein-cholesterol (LDL-C), sex and smoking. There were 19 cases of cardiac death (7...
