New randomized trial results show no benefit in clinical outcomes from active surveillance using functional testing over usual care among high-risk patients with previous percutaneous coronary intervention (PCI).
At 2 years, there was no difference in a composite outcome of death from any cause, MI, or hospitalization for unstable angina between patients who had routine functional testing at 1 year and patients receiving standard care in the POST-PCI trial.
Dr. Duk-Woo Park
“Our trial does not support active surveillance with routine functional testing for follow-up strategy in high-risk patients who undergo PCI,” first author Duk-Woo Park, MD, division of cardiology, Asan Medical Center, University of Ulsan, Seoul, South Korea, said in an interview.
The researchers said their results should be interpreted in the context of previous findings from the ISCHEMIA trial that showed no difference in death or ischemic events with an initial invasive versus an initial conservative approach in patients with stable coronary artery disease and moderate to severe ischemia on stress testing.
“Both the ISCHEMIA and POST-PCI trials show the benefits of a ‘less is more’ concept (i.e., if more invasive strategies or testing are performed less frequently, it will result in better patient outcomes),” the authors wrote. Although characteristics of the patients in these trials “were quite different, a more invasive therapeutic approach (in the ISCHEMIA trial) as well as a more aggressive follow-up approach (in the POST-PCI trial) did not provide an additional treatment effect beyond a conservative strategy on the basis of guideline-directed medical therapy.”
Results were presented at the annual congress of the European Society of Cardiology and published online simultaneously in the New England Journal of Medicine.
‘Compelling new evidence’
In an editorial accompanying the publication, Jacqueline E. Tamis-Holland, MD, Icahn School of Medicine at Mount Sinai, Mount Sinai Morningside Hospital, New York, also agreed that this new result “builds on the findings” from the ISCHEMIA trial. “Collectively, these trials highlight the lack of benefit of routine stress testing in asymptomatic patients.”
Dr. Tamis-Holland pointed out that many of the deaths in this trial occurred before the 1-year stress test, possibly related to stent thrombosis, and therefore would not have been prevented by routine testing at 1 year. And overall, event rates were “quite low, and most likely reflect adherence to guideline recommendations” in the trial. For example, 99% of patients were receiving statins, and 74% of the procedures used intravascular imaging for the PCI procedures, “a much greater proportion of use than most centers in the United States,” she noted.
“The POST-PCI trial provides compelling new evidence for a future class III recommendation for routine surveillance testing after PCI,” Dr. Tamis-Holland concluded “Until then, we must refrain from prescribing surveillance stress testing to our patients after PCI, in the absence of other clinical signs or symptoms suggestive of stent failure.”
Commenting on the results, B. Hadley Wilson, MD, executive vice chair of the Sanger Heart & Vascular Institute/Atrium Health, clinical professor of medicine at University of North Carolina at Chapel Hill, and vice president of the American College of Cardiology, said that for decades it’s been thought that patients who had high-risk PCI needed to be followed more closely for potential future events.
“And it actually turned out there was no difference in outcomes between the groups,” he said in an interview.
“So, I think it’s a good study – well conducted, good numbers – that answers the question that routine functional stress testing, even for high-risk PCI patients, is not effective or cost effective or beneficial on a yearly basis,” he said. “I think it will help frame care that patients will just be followed with best medical therapy and then if they have recurrence of symptoms they would be considered for further evaluation, either with stress testing or angiography.”
High-risk characteristics
Current guidelines do not advocate the use of routine stress testing after revascularization, the authors wrote in their paper. “However, surveillance with the use of imaging-based stress testing may be considered in high-risk patients at 6 months after a revascularization procedure (class IIb recommendation), and routine imaging-based stress testing may be considered at 1 year after PCI and more than 5 years after CABG [coronary artery bypass graft] (class IIb recommendation).”
But in real-world clinical practice, Dr. Park said, “follow-up strategy for patients who underwent PCI or CABG is still undetermined.” Particularly, “it could be more problematic in high-risk PCI patients with high-risk anatomical or clinical characteristics. Thus, we performed this POST-PCI trial comparing routine stress testing follow-up strategy versus standard-care follow-up strategy in high-risk PCI patients.”
The researchers randomly assigned 1,706 patients with high-risk anatomical or clinical characteristics who had undergone PCI to a follow-up strategy of routine functional testing, including nuclear stress testing, exercise electrocardiography, or stress echocardiography at 1 year, or to standard care alone.
High-risk anatomical features included left main or bifurcation disease; restenotic or long, diffuse lesions; or bypass graft disease. High-risk clinical characteristics included diabetes mellitus, chronic kidney disease, or enzyme-positive acute coronary syndrome.
Mean age of the patients was 64.7 years; 21.0% had left main disease, 43.5% had bifurcation disease, 69.8% had multivessel disease, 70.1% had diffuse long lesions, 38.7% had diabetes, and 96.4% had been treated with drug-eluting stents.
At 2 years, a primary-outcome event had occurred in 46 of 849 patients (Kaplan-Meier estimate, 5.5%) in the functional-testing group and in 51 of 857 (Kaplan-Meier estimate, 6.0%) in the standard-care group (hazard ratio, 0.90; 95% confidence interval, 0.61-1.35; P = .62). There were no between-group differences in the components of the primary outcome.
Secondary endpoints included invasive coronary angiography or repeat revascularization. At 2 years, 12.3% of the patients in the functional-testing group and 9.3% in the standard-care group had undergone invasive coronary angiography (difference, 2.99 percentage points; 95% CI, −0.01 to 5.99 percentage points), and 8.1% and 5.8% of patients, respectively, had a repeat revascularization procedure (difference, 2.23 percentage points; 95% CI, −0.22 to 4.68 percentage points).
Positive results on stress tests were more common with nuclear imaging than with exercise ECG or stress echocardiography, the authors noted. Subsequent coronary angiography and repeat revascularization were more common in patients with positive results on nuclear stress imaging and exercise ECG than in those with discordant results between nuclear imaging and exercise ECG.
POST-PCI was funded by the CardioVascular Research Foundation and Daewoong Pharmaceutical Company. Dr. Park reported grants from the Cardiovascular Research Foundation and Daewoong Pharmaceutical Company. Dr. Tamis-Holland reported “other” funding from Pfizer outside the submitted work. Dr. Wilson reported no relevant disclosures.
A version of this article first appeared on Medscape.com.