The Prevalence of Coronary Spasm in Hypertensive Patients Treated With Antihypertensive Medication

• Development of significant CAS [ Time Frame: baseline ]
  During the Ach provocation test, significant CAS was recorded when present, and investigators recorded whether is was associated with any of the following criteria: 1) >70% luminal narrowing on coronary angiography; 2) >70% luminal narrowing on coronary angiography and concurrent chest pain;3) >70% luminal narrowing on coronary angiography, concurrent chest pain and EKG changes(ST-segment elevation or depression ≥1mm); 4) >90% luminal narrowing induced by A3 dose on coronary angiography and concurrent chest pain.
  
  

• Transient high-grade AV block [ Time Frame: baseline ]
  Transient high-grade AV block that occurred in response to Ach injection is defined as such if it consisted of multiple sequential P waves that should conduct, but did not.
  
  

• incidence of CAS in each antihypertensive agent. [ Time Frame: : baseline ]
  comparison of CAS incidence in each antihypertensive agent
  
  

A total of consecutive patients in the CAS registry of the Cardiovascular Center at Korea University Guro Hospital and who had resting chest pain without significant coronary lesions (luminal narrowing <50%) underwent a provocation test with Ach infusion during coronary angiography from November 2004 to May 2012 will be reviewed. Among them, patients with documented cardiovascular disease and/or any other serious medical condition, such as an increased serum creatinine level (>2mg/dl), will be excluded. Patients will be excluded due to incomplete data. The investigators will register hypertensive patients who are currently using antihypertensive medications. The study population will be divided into quartiles based on rising systolic BP, diastolic BP, and pulse pressure. CAS+chest pain(CP) means>70% luminal narrowing on Ach provocation test. and/or concurrent typical chest pain.

BP was measured with a noninvasive BP monitoring device with the patient lying on the angiographic table after a five-minute rest (Patient monitoring system, NP 30:Philips, Amsterdam, The Netherlands). The first reading was discarded, and the mean of the next two consecutive readings was used. Next, coronary angiography was performed. Hypertension is defined as systolic BP ≥140mmHg and/or diastolic BP ≥90mmHg on at least two consecutive readings in the outpatient clinic. Patients taking antihypertensive medications are also categorized as hypertensives. Other Risk factors for CAS examined in this study include hyperlipidemia (total cholesterol level ≥200mg /dl or current medication with lipid-lowering drugs), diabetes (fasting blood glucose≥126mg /dl, and/or glycated Hemoglobin A1c level more than 6.5% or current use of medications), current smoker (active smoking within the past 12 months), and current alcohol user (at least 1 alcohol drinking a week).