AMC Heart Institute's 8th publication on the NEJM, a standard to worldwide medical professionals

AMC team analysis to evaluate the efficacy on routine functional testing of high-risk patients after PCI

“Most desirable to test according to symptoms for the efficient use of medical resources”

▲ (from the left) Professor Duk-Woo Park, Professor Seung-Jung Park, and Professor Do-Yoon Kang 

A routine functional testing is performed after percutaneous cardiac interventions (PCI) as a follow-up to check cardiovascular function. For the first time in the world, AMC team verified the effect of these routine surveillance functional testing after PCI, a call to action for new global approaches.

For the past 20 years, routine functional testing such as nuclear stress testing, exercise electrocardiograpy, and stress echocardiograpy have been regularly performed on high-risk PCI patients to prevent restenosis or cardiac ischemic event, caused due to decreased blood flow to the heart.

However, Asan Medical Center (AMC) team led by Professor Duk-Woo Park, Professor Seung-Jung Park, and Professor Do-Yoon Kang of the Division of Cardiology found that there is no difference in the incidence of major cardiovascular events or death in high-risk patients who underwent routine functional testing, compared with standard care, after PCI.

This study has been published in the latest issue of the ‘New England Journal of Medicine (NEJM),’ a journal considered the textbook for worldwide medical professionals, and is expected to be reflected in the guidelines to refrain from mandatory stress testing on high-risk patients after PCI.

The NEJM is one of the world’s most prestigious medical journal with an impact factor (I.F.), reflecting the number of citations of published article, of 176.079. Over the past decades, clinical studies published in the NEJM have been reflected in textbooks, effecting the worldwide clinical practice.

Percutaneous cardiac interventions (PCI) is a procedure using a coronary stent to open clogged blood vessels and is the most common standard treatment for patients with coronary artery diseases such as angina or myocardial infarction.

Routine functional testing, usually performed 1 year after PCI, were the guideline recommendations from clinical doctors. However, whether routine functional testing improves the outcome among in high-risk patients after PCI has been uncertain until recently.

AMC team led by Professor Duk-Woo Park conducted a multicenter, pragmatic, randomized superiority trial with 1,706 high-risk patients who underwent PCI at 11 hospitals in Korea. The trial compared 849 patients who performed routine functional testing 1 year after the procedure and 857 patients who only underwent standard-care strategy.

Patients were an average of 64.7 years old with at least one anatomical feature or clinical characteristics such as left main disease, bifurcation disease, an ostial lesion, a chronic total occlusion, multivessel coronary artery disease, diabetes mellitus, and chronic renal failure. Also, the researchers evaluated the incidence of major clinical events such as death, myocardial infarction, or hospitalization for unstable angina.

As a result, at 2 years after PCI, the incidence of major clinical events was 5.5% in the group with routine stress functional testing and 6.0% in the group which did not. Thus, there was no significant difference between the two groups.

Therefore, the team concluded that routine functional testing after 1 year of PCI in high-risk patients should be conducted when there are other clinical signs or symptoms suggestive of stent failure such as chest pain rather than mandatory testing. This is expected to have influence on the appropriate operation of medical system with no difference in patient safety.

As a result, a total of 8 publications have been published in the NEJM by medical professionals at AMC Heart Institute as the first author or corresponding authors.

AMC Heart Institute published 6 papers on the NEJM by the Interventional Team led by Professor Seung-Jung Park, who published Korea’s first paper on the NEJM in 2003, and Professor Duk-Hyun Kang, specialized in valve diseases, published 2 papers on the NEJM.

In particular, Professor Seung-Jung Park is Asia’s first to be the corresponding author in all 6 papers on the NEJM, one of world’s best achievements.

Professor Duk-Woo Park explained, “This is the first multicenter, randomized superiority clinical study to evaluate the efficacy of routine functional testing after PCI which had been undetermined. This study is significant for the public interest in minimizing clinically undetermined testing and is expected to have a direct impact on actual patient care."

He added, "High-risk patients after PCI often prefer routine functional testing due to concerns about recurrence even though they are asymptomatic. However, for the efficient use of medical resources, it is most desirable to comprehensively judge symptoms or various clinical conditions to determine whether patients should be tested or treated accordingly."

The study has been published on the NEJM in real time while being announced as the ‘Late-breaking Science’ at the European Society of Cardiology (ESC) Congress 2022 held in Barcelona, Spain, on August 28^th.