228. A predictive model of perioperative myocardial infarction in spine surgery

Abstract

BACKGROUND CONTEXT Emphasis has been placed upon reducing perioperative complications in spinal operations, of which cardiac complications remain among the most devastating for patients. Myocardial infarction (MI), along with its predictive factors, has been an understudied complication. PURPOSE To assess the incidence and risk factors for perioperative myocardial infarctions in spine surgery patients. STUDY DESIGN/SETTING Retrospective case control study PATIENT SAMPLE A total of 196,086 surgical spine patients OUTCOME MEASURES Predictors of MI following surgical spine intervention METHODS A patient was categorized as having sustained a postsurgical MI in this study if it occurred intraoperatively or within 30 days of surgery, manifested by documentation of ECG changes accordingly: ST elevation >1mm in two or more contiguous leads, new left bundle branch, new Q-wave in two or more contiguous leads, or new elevation in troponin greater than three times upper level of the reference range. The relationship between MI and non-MI spine patients was assessed using chi-squared and independent samples t-tests, as appropriate. Descriptive statistics, including frequency counts for categorical variables and means and standard deviations, were calculated to summarize demographics and clinical profiles such as spinal diagnoses and comorbidity. Univariate/multivariate analyses were run to assess predictive factors of MI in spine surgery patients. Logistic regression with stepwise model selection was employed to create a model to predict MI occurrence. RESULTS Of 196,523 patients (57.1±14.2 years, 48% female, 30.4±6.5 kg/m2) undergoing elective spine surgery, 436 patients had an acute MI intraoperatively or within 30 days postoperatively (Spine-MI) (69.07±10.4 years, 42% female, 30.39±6.22 kg/m2). Incidence of MI did not change significantly from 2010 to 2016 (0.2% to 0.3%, p=0.298). Spine-MI patients underwent significantly more fusions than elective spine surgical patients who did not have an MI (73.6% vs 58.4%, p CONCLUSIONS A model with good predictive capacity to predict MI after spine surgery now exists. Predictive modeling of myocardial infarction following spine operations can aid in risk-stratification of patients, consequently improving preoperative patient counseling and optimization in the peri-operative period. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.