Use of stress testing and diagnostic catheterization after coronary stenting: association of site-level patterns with patient characteristics and outcomes in 247,052 Medicare beneficiaries.

OBJECTIVES: The aim of this study was to determine diagnostic testing patterns after percutaneous coronary intervention (PCI).
BACKGROUND: Little is known about patterns of diagnostic testing after PCI in the United States or the relationship of these patterns to clinical outcomes.
METHODS: Centers for Medicare and Medicaid Services inpatient and outpatient claims were linked to National Cardiovascular Data Registry CathPCI Registry data from 2005 to 2007. Hospital quartiles of the cumulative incidence of diagnostic testing use within 12 and 24 months after PCI were compared for patient characteristics, repeat revascularization, acute myocardial infarction, and death.
RESULTS: A total of 247,052 patients underwent PCI at 656 institutions. Patient and site characteristics were similar across quartiles of testing use. There was a 9% and 20% higher adjusted risk for repeat revascularization in quartiles 3 and 4 (highest testing rate), respectively, compared with quartile 1 (lowest testing rate) (p = 0.020 and p < 0.0001, respectively). The adjusted risk for death or acute myocardial infarction did not differ among quartiles.
CONCLUSIONS: Although patient characteristics were largely independent of rates of post-PCI testing, higher testing rates were not associated with lower risk for myocardial infarction or death, but repeat revascularization was significantly higher at these sites. Additional studies should examine whether increased testing is a marker for improved quality of post-PCI care or simply increased health care utilization.