A systematic comparative effectiveness review of noninvasive testing for coronary artery disease found there was no significant difference in MI or all-cause mortality between testing strategies across settings and pretest risk groups.

The Agency for Healthcare Research and Quality (AHRQ) conducted the review and released the report on March 29.

The rates of all-cause mortality were low: 0 percent to 1.5 percent in outpatient settings and 0 percent to 1.1 percent in emergency department settings. The rates for MI were also low: 0 percent to 0.8 percent in outpatient settings and 0 percent to 3 percent in emergency department settings.

The authors also mentioned that invasive coronary angiography was more common following coronary CT angiography than after functional tests. In addition, referral revascularization was more common following coronary CT angiography versus functional testing in general but was similar compared with single-photon emission CT or usual care.

The authors noted that coronary artery disease is the leading cause of death globally and causes one of six deaths in the U.S. Each year, approximately 635,000 people in the U.S. have a new coronary event, 280,000 have a recurrent ischemic event and 150,000 have a silent first MI.

A panel from the Duke Evidence-based Practice Center’s Cardiovascular Topic Identification project nominated noninvasive testing for coronary artery disease as a priority topic. The preliminary questions were posed on AHRQ’s website for four weeks for public comment. The authors used those public comments and input from the technical panel to develop the final list of questions and the protocol.

The authors identified 46 randomized, observational and noncomparative studies that met their criteria. Of those, they evaluated 24 comparative studies that examined the impact of noninvasive testing on clinical outcomes and/or clinical management outcomes: 14 were randomized controlled trials and 10 were comparative observational studies.

The authors mentioned they could not make conclusions about low-risk and high-risk patients without acute coronary syndrome. They also could not make judgments regarding radiation exposure for the initial test or subsequent tests.

“Future research using more refined evidence-based definitions of pretest risk, coupled with information on post-test risk stratification, its impact on clinical management (treatment and referral for additional testing), and longer term followup to assess clinical outcomes, is needed to determine optimal testing strategies and roles of tests in different pretest risk groups,” they wrote.