JACC: Is stress testing after revascularization overused?

Stress imaging at 60 minutes Image source: Richard M. Fleming, MD, cardiologist at the Cardiovascular Institute of Southern Missouri

While more than 50 percent of patients had at least one stress test performed within 24 months of revascularization, only 5 percent required repeat revascularization, suggesting that the role of stress testing post-revascularization procedures needs to be redefined, according to a study published in the Oct. 12 issue of the Journal of the American College of Cardiology.

Because stress testing data is limited, Bimal R. Shah, MD, MBA, of the Duke University Medical Center in Durham, N.C., and colleagues set out to study the pattern of cardiac stress testing after coronary revascularization in community practice.

The researchers used the national health insurance claims database (United Healthcare) that included 28,177 patients undergoing revascularization procedures—21,046 PCI procedures and 7,131 CABG procedures—between July 1, 2004, and June 30, 2007.

According to Shah and colleagues, the 12-month cumulative incidence of testing was 36 percent overall—39 percent for PCI patients and 28 percent for CABG patients. Additionally, 59 percent of these patients had at least one cardiac stress test performed within 24 months of revascularization—61 percent of PCI patients and 51 percent of CABG patients.

While nuclear imaging was the main testing method used, the researchers said that the incidence of stress testing increased six and 12 months after revascularization. The researchers said the increased number of tests could have been directly linked to follow-up office visits.

Additionally, the authors reported that only 11 percent of patients underwent cardiac cath post-imaging testing, and only 5 percent underwent repeat revascularization.

After the researchers stratified patients by age, sex and comorbid conditions, they found that more patients without diabetes and congestive heart failure were tested compared to those with the conditions.

“Cardiologists are under considerable scrutiny for overuse of imaging and testing,” the authors wrote. “Variation in clinical practice matters because uncertainty about the appropriate application of stress testing leads to more testing overall. Additionally, mounting evidence suggests that excessive testing results in unnecessary and nontrivial radiation exposure.

“Our study suggests that there is significant opportunity to implement American College of Cardiology Foundation (ACCF) appropriate use criteria (AUC)  to ensure the appropriate and efficient use of cardiac stress testing,” the authors concluded. “Further studies are warranted to investigate specific drivers for stress testing and the possible role of ACCF AUC in guiding clinical decision-making.”

In an accompanying JACC editorial, George A. Beller, MD, of the University of Virginia in Charlottesville, Va., wrote that this study serves as "another wake-up call to cardiovascular specialists to be more diligent in adhering to evidence-based practice guidelines and AUC.

"The value of stress imaging is greatest in the evaluation of risk for future cardiac events in symptomatic patients to identify those who would benefit the most from revascularization strategies."

Additionally, Beller wrote that getting pre-authorization from payors includes "no evidence for improved quality of care, the favoring of indiscriminate volume reduction, the lack of transparency, the fact that such measures are not based on AUC, inconsistent processes often characterized by confusion and inefficiency, reduced timeliness, an unstated goal of steerage to the test of least resistance, labor intensiveness, and scant data available for feedback or education.

"Thus, it behooves cardiovascular specialists to advocate for and adhere to accepted AUC developed by our own scientific societies," he concluded.