Routine Stress Testing Didn’t Offer Benefits to High-Risk Patients Post-PCI

BARCELONA – Routine functional testing after percutaneous cardiac interventions (PCI) did not boost clinical outcomes at 2 years in high-risk patients, according to the POST-PCI trial.

The composite endpoint of death from any cause, myocardial infarction, or hospitalization for unstable angina was experienced by 5.5% of patients who got routine functional testing versus 6.6% in the standard-care group, for a 0.90 hazard ratio (95% CI 0.61-1.35, P=0.62), reported Duk-Woo Park, MD, PhD, of the Asan Medical Center/University of Ulsan College of Medicine in Seoul.

Also at 2 years, 12.3% of the patients in the functional-testing group underwent invasive coronary angiography versus 9.3% in the standard-care group for a non-significant difference, he said in a presentation at the European Society of Cardiology (ESC) meeting. The results were simultaneously published in the New England Journal of Medicine (NEJM).

And there was no significant difference between the percentage of patients who required repeat revascularization (8.1% vs 9.3%, respectively), according to Park and colleagues.

The authors pointed out that the “routine stress-testing strategy appeared to be associated with more frequent invasive coronary angiography and repeat revascularization after 1 year, which did not result in a significant reduction in major cardiovascular events or mortality.”

The findings seem to confirm recent clinical practice in the U.S., explained B. Hadley Wilson, MD, vice president of the American College of Cardiology (ACC). “Standard of care in this study is guideline-directed medical therapy for patients with ischemic heart disease and those who have had high-risk PCI or continuing to follow patients with the best medical therapy and monitoring them to see if they develop symptoms versus what was traditional standard of care of stress testing at 1 year or 2 years in these high-risk patients.” He is at the University of North Carolina School of Medicine at Chapel Hill.

Wilson, who was not involved in the study, noted that these types of stress tests “are a huge drain on the healthcare system and [a drain] on the patients as well…this study…may change practice. We may see this routine stress testing melt away.”

Park and colleagues assigned 1,706 PCI patients with high-risk anatomical or clinical characteristics who do routine functional testing — such as nuclear stress testing, exercise electrocardiography, or stress echocardiography — at 1 year post-PCI or to PCI standard care alone.

The mean age of patients was 64.7 and over three-fourths were male. Among the patients, 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.

Park’s group acknowledged that “the observed number of primary-outcome events was lower than expected. This discrepancy might be explained in part by differences between clinical or lesion characteristics, interventional practice, or race or ethnic group. Also, it may be due to advances in PCI methods and improvements in cardiovascular care over the past decade.”

In an NEJM accompanying editorial, Jacqueline E. Tamis-Holland, MD, of the Icahn School of Medicine at Mt. Sinai in New York city, highlighted that the low rate of events might “reflect adherence to guideline recommendations,” such as those from the ACC/American Heart Association that Tamis-Holland co-authored.

POST-PCI limitations included the fact that the follow-up strategy was not masked from the patients and investigators, so ascertainment bias was a possibility. Also, women were underrepresented in the trial. Finally, “routine stress testing included three different types of methods with diagnostic accuracy varying across the tests,” so “applying these different tests might result in inconsistent judgment of a patient’s ischemic burden and affect clinical responses,” Park’s group stated.

Still, Tamis-Holland emphasized that POST-PCI offered “compelling new evidence for a future class III recommendation for routine surveillance testing after PCI. 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.”