Deferring testing is a safe treatment option for chest pain patients who face a low risk of coronary artery disease (CAD), according to a new analysis published in JAMA Cardiology.[1] It also can help reduce the number of cardiac catheterizations and low-yield diagnostic tests being performed, which saves time and can reduce healthcare costs.
“In people presenting with stable chest pain or other symptoms suggestive of CAD, functional stress testing or anatomic coronary imaging is often performed as an initial evaluation step,” wrote lead author James E. Udelson, MD, a cardiologist with Tufts Medical Center in Boston, and colleagues. “However, the yield of initial testing is low.”
Noting that current U.S. and European guidelines recommend deferring diagnostic testing if a “pretest probability model” is able to determine the patient is at a low risk of obstructive CAD, Udelson et al. aimed to examine how such a policy may or may not impact patient symptoms and outcomes. The group explored data from more than 2,100 patients who originally participated in the PROMISE trial, using a PROMISE minimal risk score (PMRS) to identify patients at a “very low risk” of obstructive CAD or adverse outcomes. Approximately 20% of patients had a low enough PMRS score that they were categorized as being low-risk CAD patients. These patients were randomized to either have all testing deferred as recommended by U.S. and European guidelines or undergo usual testing.
Among patients who had their testing deferred, 64% never underwent testing over the study’s follow-up period of one year. The remaining 36% eventually underwent downstream testing after a median time period of 48 days “based on ongoing or worsening symptoms.” Results were completely normal for 96% of patients when they did undergo testing.
For patients who underwent usual testing, meanwhile, the most common modalities were functional stress tests (83%) and coronary angiography (3%). Another 13% ultimately ended up not undergoing any tests for their chest pain during the follow-up period.
The study’s primary endpoint, a composite of all-cause death, nonfatal myocardial infarction (MI) and catheterization without obstructive CAD, was seen in 0.9% patients in the deferred group and 6.3% of patients in the usual testing group. No deferred patients experienced death or a nonfatal MI. One noncardiovascular death and one MI were seen in the group that was tested like normal. The biggest difference between the two groups was the fact that 0.9% of patients in the deferred group underwent catheterizations without obstructive CAD compared to 5.8% in the usual testing group.
“In symptomatic people with suspected CAD, identification of individuals at minimal risk for obstructive CAD and outcome events by the PMRS enabled a strategy of initial deferred testing with patient consent,” the authors wrote. “In this trial, the strategy was safe with no observed adverse outcome events, fewer invasive catheterizations without significant CAD, and fewer low-yield noninvasive tests compared with a usual testing strategy. Symptoms diminished over time to a similar degree as the alternative strategy of initial functional testing or catheterization.”
These findings, the team added, “support existing guideline recommendations” related to deferred diagnostic testing.
“Implementation of this approach has the potential to safely reduce very low-yield testing and improve care and the efficiency of testing for suspected CAD,” the authors concluded.
Michael has more than 16 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.