Percutaneous coronary intervention (PCI) relieves stable chest pain and improves exercise capacity among patients taking little or no chest pain medication, research presented at the American Heart Association’s 2023 Scientific Sessions (11–13 November, Philadelphia, USA) has shown.
Previously, the ORBITA trial published in 2017, had shown that stenting did not improve exercise tolerance or chest pain any more than a placebo procedure. It proved the feasibility of conducting placebo-controlled trials of established interventional procedures and made it possible to design subsequent research applied to a wider population of patients and clinical practice.
“However, it is possible that the effect of stenting in ORBITA was diminished by high levels of guideline-directed background, antianginal medication, which are difficult to achieve in clinical practice,” said Rasha Al-Lamee (Imperial College London and Imperial College Healthcare NHS Trust, London, UK).
ORBITA-2 enrolled a broader range of 301 patients with both single and multivessel disease who were randomly assigned to either coronary stenting or a placebo procedure. Neither patients nor the medical or research teams were aware of which procedure they had received. Throughout the trial, patients reported whether they were experiencing chest pain every day using a dedicated smartphone application. These daily symptom reports and the need for chest pain medication were used to calculate the angina symptom score, which is a first-of-its-kind primary study endpoint.
“We calculated an ‘angina symptom score’ daily for each participant based mainly on how much chest pain they experienced and their need for antianginal medication. We found that stents improved symptoms compared to the placebo procedure,” Al-Lamee said.
The study found that patients who had stents were three times more likely to be free from angina at the end of the trial compared to patients who had the placebo procedure. Stenting improved the angina symptom score, with follow-up scores of 2.9 in the PCI group and 5.6 in the placebo group.
Exercise time increased by 60 seconds more among patients who received stenting compared to patients who received the placebo procedure, and the effect of stenting was immediate and sustained during the 12-week follow-up period.
“We expected that PCI would be more effective than a placebo procedure in patients taking little or no chest pain medication, and indeed, the results proved our hypothesis was correct,” Al-Lamee said. “Going forward, patients and medical teams have a choice of two pathways for chest pain relief: chest pain medication or PCI. The key finding of this trial is that it is the first therapy initiated that seems to have the maximum effect. Although PCI is neither risk-free nor cost-free, its use as an upfront procedure can now be considered evidence-based.”
“The ORBITA and ORBITA-2 trials together suggest the American and European guidelines for stable coronary artery disease may require updating. Perhaps restricting stenting to patients with inadequate response to chest pain medications may inadvertently be selecting the group of patients with the least to gain,” Al-Lamee said.
Finally, Al-Lamee said: “I hope that the two trials will be used together to give patients and medical teams the choice of two treatment strategies with similar levels of benefit. They each have their own benefits, risks and limitations that should form part of the decision-making process. Importantly, the first therapy administered, antianginal medication or PCI as an antianginal procedure, appears to deliver most of the available symptomatic response.”
The study was presented by Christopher Rajkumar (Imperial College London, London, UK) with simultaneous publication in The New England Journal of Medicine.
“The ORBITA-2 trial is a well-designed and executed study despite great challenges,” said George Dangas (Icahn School of Medicine at Mount Sinai, New York, USA) president of the Society for Cardiovascular Angiography & Interventions (SCAI), commenting on the presentation of the trial’s results. “While study enrolment was small the results show unequivocal anginal benefit from PCI, without the use of medication in ischaemic patients.
“SCAI recommends the use of PCI for symptom relief in appropriate patients. ORBITA-2 confirms the benefit of PCI in helping stable ischaemic heart disease patients, consistent with other prior trials.”