Stress testing after percutaneous coronary interventions: a population-based study
Background — Routine stress testing is commonly used after percutaneous coronary intervention (PCI) to detect in-stent restenosis or suboptimal procedure results; however, recent studies suggest that such testing is rarely indicated. Our main objectives were to assess temporal trends in utilization of stress testing and to determine factors associated with its use.
Methods — We conducted an observational study involving all patients who had undergone PCI in Ontario, Canada, from Apr. 1, 2004, to Mar. 31, 2012. The main outcome was stress testing within 2 years after PCI. We constructed multivariable logistic regression models to determine factors associated with the use of stress tests.
Results — Our cohort consisted of 128 380 patients who underwent PCI procedures. The 2-year rate of stress testing declined significantly, from 68.1% among patients who underwent PCI in 2004 to 60.4% in 2012 (p < 0.001). Similar reductions were observed regardless of patients' risk of restenosis and type of stent received. Patients who were older or had diabetes mellitus, prior myocardial infarction, heart failure or other comorbidities were significantly less likely to undergo stress testing. In contrast, patients with higher income and those whose PCI was performed in a nonteaching hospital were significantly more likely to undergo stress testing.
Interpretation — We observed a decrease in the use of stress testing after PCI procedures over time. However, stress tests were not performed in accordance with patients' higher baseline risk of adverse outcomes or risk of restenosis. Instead, many nonclinical factors, such as patients' socioeconomic status and hospitals' teaching status, were associated with higher use of stress tests.