Anticipated Rates and Costs of Guideline-Concordant Preoperative Stress Testing

BACKGROUND: Current guidelines recommend that patients have preoperative assessment of cardiac risk and functional status, and that patients at "elevated" cardiac risk with poor or unknown functional status be referred for preoperative stress testing. Little is known about current rates of testing or resultant medical costs. We set out to estimate the expected rates of preoperative stress testing and resultant costs if physicians in the United States were to follow current guidelines and to investigate differences that would arise from 2 risk prediction methods included in current guidelines. METHODS: We applied 2 risk prediction tools (Revised Cardiac Risk Index and Myocardial Infarction or Cardiac Arrest) included in current American College of Cardiology/American Heart Association guidelines to a multicenter prospective registry of patients undergoing surgery in the United States in 2009. We then calculated expected rates of preoperative cardiac stress testing if physicians were to follow American College of Cardiology/American Heart Association guidelines, expected nationwide direct medical expenditures that would result (in 2017 US dollars), and agreement beyond chance between the 2 risk prediction tools. RESULTS: Current guidelines recommend considerable spending on preoperative stress testing. Guideline-recommended spending would differ substantially depending on the risk prediction tool used and the reliability of the functional status assessment. Rates of testing and resultant spending are likely much greater among patients at "elevated" risk, compared with patients at "low" risk. Two guideline-recommended risk assessment tools, Revised Cardiac Risk Index and Myocardial Infarction or Cardiac Arrest, have poor agreement beyond chance across the currently recommended risk threshold. CONCLUSIONS: Preoperative stress testing is likely a considerable source of medical spending, despite unproven benefit. Which perioperative risk assessment tool clinicians should use, what risk thresholds are appropriate for patient selection, and the reliability of the functional status assessment all warrant further attention.