title: Outcomes among non-ST-segment elevation acute coronary syndromes patients with no angiographically obstructive coronary artery disease: observations from 37,101 patients.
abstract: OBJECTIVE
  Limited data exist concerning outcomes of patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS) with no angiographically obstructive coronary artery disease (non-obstructive CAD). We assessed the frequency of clinical outcomes among patients with non-obstructive CAD compared with obstructive CAD.
  
  
  RESULTS
  We pooled data from eight NSTE ACS randomized clinical trials from 1994 to 2008, including 37,101 patients who underwent coronary angiography. The primary outcome was 30-day death or myocardial infarction (MI). Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for 30-day death or MI for non-obstructive versus obstructive CAD were generated for each trial. Summary ORs (95% CIs) across trials were generated using random effects models. Overall, 3550 patients (9.6%) had non-obstructive CAD. They were younger, more were female, and fewer had diabetes mellitus, previous MI or prior percutaneous coronary intervention than patients with obstructive CAD. Thirty-day death or MI was less frequent among patients with non-obstructive CAD (2.2%) versus obstructive CAD (13.3%) (OR(adj) 0.15; 95% CI, 0.11-0.20); 30-day death or spontaneous MI and six-month mortality were also less frequent among patients with non-obstructive CAD (OR(adj) 0.19 (0.14-0.25) and 0.37 (0.28-0.49), respectively).
  
  
  CONCLUSIONS
  Among patients with NSTE ACS, one in 10 had non-obstructive CAD. Death or MI occurred in 2.2% of these patients by 30 days. Compared with patients with obstructive CAD, the rate of major cardiac events was lower in patients with non-obstructive CAD but was not negligible, prompting the need to better understand management strategies for this group.
authors.affiliation: Department of Cardiology, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
authors.forename: Gaetano M
authors.initials: GM
authors.lastname: De Ferrari
authors.forename: Keith A A
authors.initials: KA
authors.lastname: Fox
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: White
authors.forename: Robert P
authors.initials: RP
authors.lastname: Giugliano
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Tricoci
authors.forename: Harmony R
authors.initials: HR
authors.lastname: Reynolds
authors.forename: Judith S
authors.initials: JS
authors.lastname: Hochman
authors.forename: C Michael
authors.initials: CM
authors.lastname: Gibson
authors.forename: Pierre
authors.initials: P
authors.lastname: Théroux
authors.forename: Robert A
authors.initials: RA
authors.lastname: Harrington
authors.forename: Frans
authors.initials: F
authors.lastname: Van de Werf
authors.forename: Harvey D
authors.initials: HD
authors.lastname: White
authors.forename: Robert M
authors.initials: RM
authors.lastname: Califf
authors.forename: L Kristin
authors.initials: LK
authors.lastname: Newby
mesh_terms: D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D054058:Acute Coronary Syndrome / Q000175:diagnosis / Q000401:mortality / Q000601:surgery; D017023:Coronary Angiography / Q000379:methods; D023921:Coronary Stenosis / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D004562:Electrocardiography; D005500:Follow-Up Studies; D014943:Global Health; D062645:Percutaneous Coronary Intervention; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate / Q000639:trends; D016032:Randomized Controlled Trials as Topic; D015337:Multicenter Studies as Topic
keywords: Acute coronary syndromes; angiography; atherosclerosis; coronary disease; infarction