The benefit of percutaneous coronary intervention (PCI) for stable coronary artery disease has been hotly contested in recent years.1,2 On one hand, physicians and patients alike instinctively believe that mechanical relief of coronary stenoses is superior to optimal medical therapy in improving “hard” outcomes like myocardial infarction (MI) or death. Yet, randomized trials thus far have been unable to demonstrate the benefit of PCI beyond improvement in symptoms in patients without acute MI. Whether this was owing to limitations in prior studies or because this hypothesis was incorrect remains unclear. The anticipated International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial was designed specifically with the intention of adding further clarity to this question.3
It is in this context that the study by Lu et al4 sheds new insights. Lu et al4 considered the extent to which 1611 patients enrolled in the large China Patient-Centered Evaluative Assessment of Cardiac Events (PEACE) Prospective Study—and who received PCI in the absence of MI—benefited from treatment.5 The analysis expands our understanding of how PCI is used in the world’s most populous country in several fundamental ways. First, the study reported on patient-reported symptoms collected using the validated Seattle Angina Questionnaire (SAQ).6 Second, the study described in-hospital complications and treatment patterns among these patients. Third, the long-term benefits of PCI were reported in relation to changes in the SAQ from baseline—a critical piece of information for a procedure that in this setting largely targets quality of life.
Several key observations were worth highlighting. Approximately one-quarter of the study population had stable coronary artery disease, and one-quarter of those in the study population had no angina symptoms in the 4 weeks prior to their procedure. Even among the remaining three-quarters of the study population diagnosed with unstable angina, 175 of 1168 patients (15%) reported no angina symptoms at the time of the procedure.
But most interesting was the finding that nearly 1 in 5 patients overall had minimal symptoms with an SAQ frequency score between 90 and 100. This is a key point and raises the question of why PCI was performed at all with such little room for improvement. Possible explanations are that clinicians suspected atypical symptoms reflecting angina equivalents were present. 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.
Irrespective of these reasons, the study findings by Lu et al4 raise concern that many patients could be exposed to the risks of an invasive procedure with a low likelihood of benefit. Fortunately, in patients who did self-report angina symptoms, most (>90%) reported symptom relief at 1 year, and roughly half of patients reported improved quality of life 1 year after PCI. Complication rates in this study were overall low, likely owing to a relatively low-risk patient population and high use of radial access. Yet, 58 patients (3.6%) experienced an ischemic stroke in this study, and that seems odd in this low-risk group. If true, this may suggest an unacceptable risk to benefit ratio. Another notable result was that the average hospital length of stay (11 days) was longer than would be expected for these types of patients in western settings; this could be the subject of further cost-savings studies. Approximately 10% of patients receiving PCI did not receive aspirin, for reasons that were unclear. Lastly, a key limitation of this study was a lack of reported data on the coronary anatomic characteristics of patients who were treated with PCI with or without symptoms.
Are there any clinical implications from these results? We believe they once again raise the possibility of whether using validated, patient-reported symptom inventories to quantify angina would be a quick, low-cost mechanism that physicians and health systems could use to better identify patients who would derive symptomatic benefit from PCI. This is not done routinely, if at all, at most centers in the United States or worldwide. If used, ensuring language and cultural appropriateness of questionnaires would be critical to avoid systematic over– or under–self-reporting of symptoms. Yet, in this way, listening to your patient could provide prognostic information on the potential benefit of PCI.
The observations by Lu et al4 were timely given that the availability of PCI is growing in China, while the exact benefits of revascularization outside of the setting of acute MI remain contested.7 Its findings raised the concept of using inventories such as the SAQ to quantify symptoms for risk stratification prior to PCI and to potentially guide therapies, particularly in low-resource settings. 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.
Published: December 14, 2018. doi:10.1001/jamanetworkopen.2018.5433
Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2018 Sutton NR et al. JAMA Network Open.
Corresponding Author: Nadia R. Sutton, MD, MPH, Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan, 1150 W Medical Center Dr, 7220 Medical Science Research Bldg III, SPC 5644, Ann Arbor, MI 48109 (firstname.lastname@example.org).
Conflict of Interest Disclosures: Dr Nallamothu reported receiving funding from the National Institutes of Health, Veterans Affairs Health Services Research and Development Service, and American Heart Association; received compensation as editor-in-chief of Circulation: Cardiovascular Quality & Outcomes, a journal of the American Heart Association; and is co-inventor on US Utility Patent Number US15/356,012 (US20170148158A1) entitled “Automated Analysis of Vasculature in Coronary Angiograms” that uses software technology with signal processing and machine learning to automate the reading of coronary angiograms, held by the University of Michigan. The patent is licensed to AngioAid Inc, in which Dr Nallamothu holds ownership shares.
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