title: The incremental risk of noncardiac surgery on adverse cardiac events following coronary stenting.
abstract: BACKGROUND
  Recent coronary stent placement and noncardiac surgery contribute to the risk of adverse cardiac events, but the relative contributions of these two factors have not been quantified.
  
  
  OBJECTIVE
  This research was designed to determine the incremental risk of noncardiac surgery on myocardial infarction (MI) and coronary revascularization following coronary stenting.
  
  
  METHODS
  A U.S. retrospective cohort study of patients receiving coronary stents at Veterans Affairs medical centers between 2000 and 2010 was used to match patients undergoing noncardiac surgery within 24 months of stent placement to two patients with stents not undergoing surgery. Patients were matched on stent type and cardiac risk factors present at the time of stent placement. A composite endpoint of MI and/or cardiac revascularization for the 30-day interval post-surgery was calculated. Adjusted risk differences (RD) were compared across time periods following stent implantation, using generalized estimating equations.
  
  
  RESULTS
  We matched 20,590 surgical patients to 41,180 nonsurgical patients. During the 30-day interval following noncardiac surgery, the surgical cohort had higher rates of the composite cardiac endpoint (3.1% vs. 1.9%; RD: 1.3%; 95% confidence interval: 1.0% to 1.5%). The incremental risk of noncardiac surgery adjusted for surgical characteristics ranged from 3.5% immediately following stent implantation to 1% at 6 months, after which it remained stable out to 24 months. Factors associated with a significant reduction in risk following surgery more than 6 months post-stent included elective inpatient procedures (ΔRD: 1.8%; p = 0.01), high-risk surgery (ΔRD: 3.7%; p = 0.01), and drug-eluting stent (DES) (ΔRD: 1.3%; p = 0.01).
  
  
  CONCLUSIONS
  The incremental risk of noncardiac surgery on adverse cardiac events among post-stent patients is highest in the initial 6 months following stent implantation and stabilizes at 1.0% after 6 months. Elective, high-risk, inpatient surgery, and patients with DES may benefit most from delay from a 6-month delay after stent placement.
authors.affiliation: Section of Gastrointestinal Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Carla N
authors.initials: CN
authors.lastname: Holcomb
authors.affiliation: The Center for Surgical, Medical Acute Care Research and Transitions (C-SMART), Birmingham Veterans Administration Hospital, Birmingham, Alabama.
authors.forename: Laura A
authors.initials: LA
authors.lastname: Graham
authors.affiliation: Section of Gastrointestinal Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama; The Center for Surgical, Medical Acute Care Research and Transitions (C-SMART), Birmingham Veterans Administration Hospital, Birmingham, Alabama.
authors.forename: Joshua S
authors.initials: JS
authors.lastname: Richman
authors.affiliation: Section of Gastrointestinal Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Rhyne
authors.affiliation: Department of Surgery, Veterans Affairs Boston Health Care System, Boston University and Harvard Medical School, Boston, Massachusetts.
authors.forename: Kamal M F
authors.initials: KM
authors.lastname: Itani
authors.affiliation: Veterans Affairs Eastern Colorado Health Care System, Denver, Colorado; University of Colorado School of Medicine, Denver, Colorado.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Maddox
authors.affiliation: Section of Gastrointestinal Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama; The Center for Surgical, Medical Acute Care Research and Transitions (C-SMART), Birmingham Veterans Administration Hospital, Birmingham, Alabama. Electronic address: mhawn@uabmc.edu.
authors.forename: Mary T
authors.initials: MT
authors.lastname: Hawn
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003327:Coronary Disease / Q000209:etiology*; D003331:Coronary Vessels; D054855:Drug-Eluting Stents / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology; D009204:Myocardial Revascularization; D011183:Postoperative Complications; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D013514:Surgical Procedures, Operative; D013997:Time Factors
keywords: adverse; coronary stent; post-operative; surgery