title: Permanent cardiac pacing after a cardiac operation: predicting the use of permanent pacemakers.
abstract: BACKGROUND
  The need for permanent cardiac pacing after cardiac operations is infrequent but associated with increased morbidity and resource utilization. We identified patient risk factors for pacemaker insertion to enable development of a predictive model.
  
  
  METHODS
  Data were collected prospectively for 10,421 consecutive patients who had cardiac operations between January 1990 and December 1995. Two hundred fifty-five patients (2.4%) were identified as having received a permanent pacemaker during the same hospitalization. Logistic regression analysis was performed to determine the independent, multivariate predictors of permanent pacing. The predictive accuracy and precision of the logistic regression model was evaluated in the 1996 database of 2,236 consecutive patients by the calculation of Brier scores.
  
  
  RESULTS
  Eight independent predictors of permanent pacemaker requirement were identified. The factor-adjusted odds ratios (OR) with 95% confidence interval (CI) associated with each predictor are as follows: (1) valve replacement surgery (aortic: OR 5.8, CI 3.9-8.7; mitral: OR 4.9, CI 3.1-7.8; tricuspid: OR 8.0, CI 5.5-11.9; double: OR 8.9, CI 5.5-14.6; and triple: OR 7.5, CI 2.9-19.3); (2) repeat operation: OR 2.4, CI 1.8-3.3; (3) age 75 years or older: OR 3.0, CI 2.0-4.4; (4) ablative arrhythmia operation: OR 4.2, CI 1.9-9.5; (5) mitral valve annular reconstruction: OR 2.4, CI 1.4-4.2; (6) use of cold blood cardioplegia: OR 2.0, CI 1.2-3.6; (7) preoperative renal failure: OR 1.6, CI 1.0-2.6; and (8) active endocarditis: OR 1.7, CI 0.9-3.0. A model for postoperative permanent pacemaker requirement using the eight predictors was formulated and tested (Brier score = 0.017+/-0.003; Z = 0.18).
  
  
  CONCLUSIONS
  The proposed predictive model correlated highly with actual pacemaker use, which suggests that the requirement for pacing results from either operative trauma or increased ischemic burden. Preoperative identification of patients at increased risk of conduction disturbances may allow for earlier detection and improved treatment. Patients requiring postoperative pacing had increased morbidity and length of stay.
authors.affiliation: Division of Cardiovascular Surgery, The Toronto Hospital, Ontario, Canada.
authors.forename: R S
authors.initials: RS
authors.lastname: Gordon
authors.forename: J
authors.initials: J
authors.lastname: Ivanov
authors.forename: G
authors.initials: G
authors.lastname: Cohen
authors.forename: A L
authors.initials: AL
authors.lastname: Ralph-Edwards
mesh_terms: D000367:Age Factors; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000601:surgery; D002304:Cardiac Pacing, Artificial; D006348:Cardiac Surgical Procedures; D017115:Catheter Ablation; D016001:Confidence Intervals; D005260:Female; D006324:Heart Arrest, Induced; D006351:Heart Valves / Q000601:surgery; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D016017:Odds Ratio; D011182:Postoperative Care; D011446:Prospective Studies; D012044:Regression Analysis; D051437:Renal Insufficiency / Q000150:complications; D012086:Reoperation; D012307:Risk Factors