The explosion of percutaneous coronary intervention (PCI) in China included many procedures done in patients who had no angina symptoms and no acute MI, a study showed.
Among the 1,611 consecutive patients getting PCI in the PEACE cohort who survived to discharge, 27.5% had stable coronary artery disease and 72.5% had unstable angina.
Of those two groups, 25.7% and 15.0%, respectively, said they had no angina symptoms at the time of the procedure, Lixin Jiang, MD, PhD, of China’s Fuwai Hospital and Peking Union Medical College, and colleagues found.
Among those who did report angina symptoms at baseline, however, more than 90% had improved angina frequency 1 year after PCI. Those with milder or no angina tended to make smaller improvements on Seattle Angina Questionnaire (SAQ) scores.
“Although future research is needed to better quantify the heterogeneity in the benefits of PCI, these results have implications not only for informing patients without acute MI about PCI’s benefits or lack thereof, in light of patients’ misconceptions and overestimates of any potential benefits of PCI, but also for identifying opportunities to improve patient outcomes,” Jiang’s group said.
Findings from the study of 40 hospitals across China in 2012-2014 were published online in JAMA Network Open.
One-third of the participants were women; the average age was 61.3. Cardiovascular risk factors were common: hypertension (68.5%), dyslipidemia (50.8%), and diabetes (29.1%).
Notably, 18% of the non-acute MI patients went into PCI with minimal chest pain (SAQ angina frequency score >90) that would not have improved with the procedure anyway. Clinically-significant improvement was defined as no less than a 10-point jump on the SAQ overall or the SAQ quality-of-life score.
“This is a key point and raises the question of why PCI was performed at all with such little room for improvement,” wrote Nadia Sutton, MD, MPH, and Brahmajee Nallamothu, MD, MPH, both of University of Michigan, Ann Arbor, in an invited commentary on the PEACE study.
“Possible explanations are that clinicians suspected atypical symptoms reflecting angina equivalents were present,” they said. “It also could be that the physicians were treating ischemia detected on noninvasive testing in the hopes of improving ‘hard’ outcomes. Lastly, financial or other gain by clinicians in recommending further diagnostic and therapeutic testing must be considered.”
Moreover, these Chinese PCI recipients stayed in the hospital for a long time, Jiang and colleagues found — an average of 11 days. There were no major bleeding episodes, but the rate of in-hospital ischemic stroke reached 3.6%.
That stroke finding “seems odd in this low-risk group,” Sutton and Nallamothu commented. “If true, this may suggest an unacceptable risk to benefit ratio.”
Jiang’s group acknowledged that they were missing 1-year follow-up data for a quarter of the PEACE patients.
Moreover, the study did not report on the coronary anatomic characteristics of the patients, the editorialists pointed out.
The lack of functional data was yet another serious limitation to the study, suggested Cindy Grines, MD, of Hofstra Northwell in Manhasset, New York.
This is relevant because to be eligible for PCI in the U.S., she told MedPage Today, “stable patients should have angina despite two antianginal medications or abnormal stress test showing moderate ischemia or have an abnormal iFR/FFR [instantaneous wave-free ratio/fractional flow reserve] in the cath lab. Unfortunately this study did not report any of these variables, so it is not clear whether the PCI was indicated.”
Grines also questioned the use of the SAQ in patients with unstable angina. “Patients with unstable angina have resting symptoms of recent onset, therefore would be expected to answer ‘no’ to the SAQ which determines the frequency of stable angina with activities,” she said.
Generally, however, Sutton and Nallamothu said that it may be a good idea to use inventories like the SAQ — keeping in mind the patient’s language and cultural background — to better identify those who would derive symptomatic benefit from PCI.
“Over 100 years ago, Sir William Osler counseled his students to ‘listen to your patients’ as they are ‘telling you the diagnosis.’ A modern-day Osler may also suggest cardiologists listen to their patients because they are telling us when PCI will work,” they wrote.
The study was supported by Chinese government grants.
Study co-authors reported significant ties to industry and ownership of a patent for the Seattle Angina Questionnaire, as well as its copyright.
Jiang and Sutton disclosed no relevant conflicts of interest.
Nallamothu declared partial ownership of a patent related to technology for the automated analysis of coronary angiograms.