Author Interviews, JACC, Surgical Research / 26.12.2014

Dr. Mary T. Hawn Center for Surgical, Medical Acute Care Research, and Transitions, Birmingham Veterans Affairs Medical Center University of Alabama at Birmingham, BirminghamMedicalResearch.com Interview with: Dr. Mary T. Hawn MD, MPH Center for Surgical, Medical Acute Care Research, and Transitions, Birmingham Veterans Affairs Medical Center Section of Gastrointestinal Surgery, Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama Medical Research: What is the background for this study? What are the main findings? Dr. Hawn: Cardiac risk factors and surgical risk factors contribute to the development of postoperative adverse cardiac events, but the relative contribution of each has not been quantified. In this study, we sought to determine the incremental risk of surgery following coronary stent placement on adverse cardiac events. To answer this question we used a retrospective cohort study of VA patients with coronary stents placed during 2000-2010 undergoing non-cardiac surgery within two years of stent placement matched to patients with coronary stents not undergoing surgery.  The patients were matched on stent type (drug-eluting versus bare metal) and cardiac risk factors at the time of stent placement.  Our outcome of interest was a composite variable of myocardial infarction and coronary revascularization occurring within 30 days of surgery.  We calculated adjusted risk differences over time from stent placement using generalized estimating equations. When comparing the two cohorts, we found a higher rate of composite cardiac events in the surgical cohort compared to the cohort not undergoing surgery. The main findings in the study were that the incremental risk of surgery was greatest when the surgery occurred in the first 6 weeks following stent placement and decreased to approximately 1% after 6 months, where it remained stable out to 24 months. Surgical characteristics associated with a significant reduction in the incremental risk after 6 months following stent placement included elective, inpatient procedures, and in the setting of a drug eluting stent. (more…)