A population based study on patterns of cardiac stress testing post-coronary revascularization

Unless prompted by symptoms or change in clinical status, the appropriate use criteria (AUC) consider cardiac stress testing (CST) within two years of percutaneous coronary intervention (PCI) and five years of coronary artery bypass grafting (CABG) to be rarely appropriate. Little is known regarding the use and yield of CST after PCI and CABG in contemporary Canadian practice. We studied 39,648 patients treated with coronary revascularization (29,497 PCI; 10,151 CABG) between 04/2004 and 03/2012 in Alberta, Canada. Frequency of CST within 2 years of revascularization, performed before repeat angiography, revascularization, or myocardial infarction was determined from linked provincial databases. Yield was defined as subsequent rates of coronary angiography and revascularization after CST. Post-PCI, 16,741 (56.8%) patients underwent CST within 2 years, while post-CABG, 4,751 (46.8%) patients underwent CST. The majority of CST occurred early within the first 180 days (PCI 79%; CABG 71%) (Figure). Patients undergoing CST were more likely to be of younger age, reside in an urban area, have higher household income, but have less medical comorbidities including diabetes, hypertension, myocardial infarction, congestive heart failure, cerebrovascular disease, peripheral vascular disease, renal failure and chronic obstructive pulmonary disease. Among PCI patients undergoing CST, 4.1% underwent subsequent coronary angiography, and 2% underwent repeat revascularization within 60 days of CST. Rates of coronary angiography and repeat revascularization post-CST were lower among CABG patients (3.3% and 1.1%, respectively). Approximately one-half of patients undergo CST within 2 years of revascularization. CST was preferentially performed in lower risk patients and appears to be based on non-clinical factors. The yield of such CST was low, with only 1 out of 50 tested PCI patients and 1 out of 91 tested CABG patients undergoing repeat revascularization. These findings reinforce the AUC recommendations against routine CST after revascularization. Further work is needed to aid with the selection of patients most likely to benefit from CST after revascularization.