Autonomic nerve function is involved in both blood pressure (BP) regulation and the pathogenesis of coronary artery spasm(CAS), but few studies have been published about the relationship between CAS and effect of BP lowering drugs in patients with hypertension. The purpose of this study is to investigate the incidence of CAS, atrioventricular (AV) block and effect of BP lowering drugs on CAS in hypertensive patients treated with BP lowering agents. The investigators will register consecutive patients who underwent coronary angiography with an acetylcholine (Ach)-induced provocation test. The investigators will include hypertensive patients who were taking antihypertensive drugs, and exclude patients who had a documented history of cardiovascular disease or who were not treated with antihypertensive agents. CAS is defined as >70% luminal narrowing on Ach provocation and /or concurrent chest pain. The study population will be divided into quartiles of rising systolic BP and diastolic BP. The incidence of Ach-induced CAS according to each systolic BP/diastolic BP quartile will be evaluated.