title: Clinical usefulness, angiographic characteristics, and safety evaluation of intracoronary acetylcholine provocation testing among 921 consecutive white patients with unobstructed coronary arteries.
abstract: BACKGROUND
  Coronary spasm can cause myocardial ischemia and angina in patients with and those without obstructive coronary artery disease. However, provocation tests using intracoronary acetylcholine administration are rarely performed in clinical routine in the United States and Europe. Thus, we assessed the clinical usefulness, angiographic characteristics, and safety of intracoronary acetylcholine provocation testing in white patients with unobstructed coronary arteries.
  
  
  RESULTS
  From September 2007 to June 2010, a total of 921 consecutive patients (362 men, mean age 62±12years) who underwent diagnostic angiography for suspected myocardial ischemia and were found to have unobstructed coronary arteries (no stenosis ≥50%) were enrolled. The intracoronary acetylcholine provocation testing was performed directly after angiography according to a standardized protocol. Three hundred forty-six patients (35%) reported chest pain at rest, 222 (22%) reported chest pain on exertion, 238 (24%) reported a combination of effort and resting chest pain, and 41 (4%) presented with troponin-positive acute coronary syndrome. The overall frequency of epicardial spasm (>75% diameter reduction with angina and ischemic ECG shifts) was 33.4%, and the overall frequency of microvascular spasm (angina and ischemic ECG shifts without epicardial spasm) was 24.2%. Epicardial spasm was most often diffuse and located in the distal coronary segments (P<0.01). No fatal or irreversible nonfatal complications occurred. However, 9 patients (1%) had minor complications (nonsustained ventricular tachycardia [n=1], fast paroxysmal atrial fibrillation [n=1], symptomatic bradycardia [n=6], and catheter-induced spasm [n=1]).
  
  
  CONCLUSIONS
  Epicardial and microvascular spasm are frequently found in white patients with unobstructed coronary arteries. Epicardial spasm is most often diffuse and located in the distal coronary segments. The intracoronary acetylcholine provocation test is a safe technique to assess coronary vasomotor function.
authors.affiliation: Robert-Bosch-Krankenhaus, Department of Cardiology, Stuttgart, Germany (P.O., A.A., S.H. T.S., H.M., U.S.); St George's University of London, Clinical Trials Unit, London, United Kingdom (G.B.); and Cardiovascular Sciences Research Centre, St George's University of London, London, United Kingdom (I.V., R.B., S.K., J.C.K.).
authors.forename: Peter
authors.initials: P
authors.lastname: Ong
authors.forename: Anastasios
authors.initials: A
authors.lastname: Athanasiadis
authors.forename: Gabor
authors.initials: G
authors.lastname: Borgulya
authors.forename: Ismail
authors.initials: I
authors.lastname: Vokshi
authors.forename: Rachel
authors.initials: R
authors.lastname: Bastiaenen
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kubik
authors.forename: Stephan
authors.initials: S
authors.lastname: Hill
authors.forename: Tim
authors.initials: T
authors.lastname: Schäufele
authors.forename: Heiko
authors.initials: H
authors.lastname: Mahrholdt
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Kaski
authors.forename: Udo
authors.initials: U
authors.lastname: Sechtem
mesh_terms: D000109:Acetylcholine / Q000009:adverse effects; D000368:Aged; D002637:Chest Pain / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology; D003329:Coronary Vasospasm / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D003331:Coronary Vessels / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000502:physiology; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D014665:Vasodilator Agents / Q000009:adverse effects
chemical_list: D014665:Vasodilator Agents; D000109:Acetylcholine
keywords: acetylcholine; complications; coronary vasospasm; microvascular angina