title: Cost-effectiveness of computed tomographic angiography before reoperative coronary artery bypass grafting: a decision-analytic model.
abstract: BACKGROUND
  The risks of repeat thoracotomy can be reduced if thoracic multidetector computed tomographic angiography (CTA) is used to guide preventive surgical strategies (PSS: peripheral cardiopulmonary bypass, circulatory arrest, and non-median sternotomy). We sought to define the cost-effectiveness of CTA using a Markov model.
  
  
  RESULTS
  We studied outcomes and costs of CTA and non-CTA strategies in a modeled cohort of 10 000 patients undergoing redo coronary artery bypass grafting. Rates of PSS implementation were anticipated to follow identification of risk by CTA. Transitions, costs, and utilities were informed by our experience and the literature. Sensitivity analyses included testing a range of costs of CTA and PSS on model outcome. In the reference case, cost and quality-adjusted life years accrued with the use of CTA ($74 869, 4.63 quality-adjusted life-years) were slightly higher than nonuse ($73 471, 4.59 quality-adjusted life-years), yielding an incremental cost-effectiveness ratio of $34 950/quality-adjusted life-years. Cost of PSS (equipment and operating time) was the most significant determinant of incremental cost-effectiveness ratio. In the reference case (cost of CTA ≈$300), identification and avoidance of potential procedural difficulties with CTA rendered it cost-effective if the cost of PSS was <$12 000. Across a range of CTA costs, incremental cost-effectiveness ratio was not materially influenced by outcomes across a broad range of imputed values.
  
  
  CONCLUSIONS
  The cost of CTA appears justified in the setting of isolated reoperative coronary artery bypass grafting, because it aids in appropriate selection of PSS. The cost-effectiveness of this imaging seems more influenced by the costs of subsequent PSS than by the cost of CTA.
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
authors.forename: Hemal
authors.initials: H
authors.lastname: Gada
authors.forename: Milind Y
authors.initials: MY
authors.lastname: Desai
authors.forename: Thomas H
authors.initials: TH
authors.lastname: Marwick
mesh_terms: D017023:Coronary Angiography / Q000191:economics* / Q000379:methods; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000191:economics*; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D006801:Humans; D008390:Markov Chains; D018803:Models, Economic; D009010:Monte Carlo Method; D061330:Multidetector Computed Tomography / Q000191:economics*; D018579:Patient Selection; D011237:Predictive Value of Tests; D011300:Preoperative Care / Q000191:economics; D019057:Quality-Adjusted Life Years; D012086:Reoperation / Q000191:economics; D013908:Thoracotomy / Q000191:economics; D013997:Time Factors