Cardiac Stents Offer No Relief for Stable Angina

A new study has concluded that percutaneous coronary intervention (PCI) is no better than a placebo procedure at providing relief to stable angina patients.

Researchers at Imperial College London (ICL; United Kingdom), Queen Mary, University of London (QMUL; United Kingdom), and other institutions conducted a blinded trial involving 230 patients with severe single-vessel stenosis, who were randomized to undergo PCI with a drug-eluting stent (DES) or a placebo procedure at five study sites in the United Kingdom. An assessment of cardiac function, including exercise time increment, was conducted at baseline and at six weeks of follow-up. The primary endpoint was difference in-between groups.

The results revealed similar improvements in exercise time with PCI (28.4 more seconds) compared to placebo (11.8 more seconds), and that most other endpoints yielded no differences either, including time to ST depression, change in peak oxygen uptake, change in the Seattle Angina Questionnaire (SAQ) physical limitation score, change in SAQ angina frequency and stability, quality of life, and the Duke treadmill score. The sole significant advantage of PCI was a greater improvement in dobutamine stress echocardiography (DSE) peak stress wall motion score index. The study was published on November 2, 2017, in The Lancet.

“Forgetting the potential magnitude of placebo effects prevents exploration of the inevitably complex relationship between anatomy, physiology, and symptoms,” concluded senior author Justin Davies, MD, and colleagues. “Clinicians have hoped there might be a simple entity named ischemia, which manifests as positive tests and clinical symptoms, and that treatment by PCI would eliminate all these manifestations concordantly; perhaps this notion is too optimistic.”

“We commend them for challenging the existing dogma around a procedure that has become routine, ingrained, and profitable. The results show once again why regulatory agencies, the medical profession, and the public must demand high-quality studies before the approval and adoption of new therapies,” commented David Brown, MD, and Rita Redberg, MD, in an accompanying editorial: “Based on these data, all cardiology guidelines should be revised to downgrade the recommendation for PCI in patients with angina, despite use of medical therapy.”

PCI, also known as coronary angioplasty, is a nonsurgical technique for treating obstructive coronary artery disease (CAD), unstable angina, and acute myocardial infarction (MI). It is usually performed by an interventional cardiologist, who feeds a catheter from the inguinal femoral artery or radial artery through the vasculature until they reach the site of blockage. X-ray imaging is used to guide the catheter threading. Angioplasty is then used to open the artery and allow blood flow, with stents used at to hold the artery open.

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Imperial College London
Queen Mary, University of London