Long‐term Cost‐Effectiveness of Diagnostic Tests for Assessing Stable Chest Pain: Modeled Analysis of Anatomical and Functional Strategies

Several tests exist for diagnosing coronary artery disease, with varying accuracy and cost. We sought to provide cost‐effectiveness information to aid physicians and decision‐makers in selecting the most appropriate testing strategy. We used the state‐transitions (Markov) model from the Brazilian public health system perspective with a lifetime horizon. Diagnostic strategies were based on exercise electrocardiography (Ex‐ECG), stress echocardiography (ECHO), single‐photon emission computed tomography (SPECT), computed tomography coronary angiography (CTA), or stress cardiac magnetic resonance imaging (C‐MRI) as the initial test. Systematic review provided input data for test accuracy and long‐term prognosis. Cost data were derived from the Brazilian public health system. Diagnostic test strategy had a small but measurable impact in quality‐adjusted life‐years gained. Switching from Ex‐ECG to CTA‐based strategies improved outcomes at an incremental cost‐effectiveness ratio of 3100 international dollars per quality‐adjusted life‐year. ECHO‐based strategies resulted in cost and effectiveness almost identical to CTA, and SPECT‐based strategies were dominated because of their much higher cost. Strategies based on stress C‐MRI were most effective, but the incremental cost‐effectiveness ratio vs CTA was higher than the proposed willingness‐to‐pay threshold. Invasive strategies were dominant in the high pretest probability setting. Sensitivity analysis showed that results were sensitive to costs of CTA, ECHO, and C‐MRI. Coronary CT is cost‐effective for the diagnosis of coronary artery disease and should be included in the Brazilian public health system. Stress ECHO has a similar performance and is an acceptable alternative for most patients, but invasive strategies should be reserved for patients at high risk.