; 104.5 seconds; P=0.036), and the reconnection of any major epicardial coronary artery with visually identifiable myocardial ischemia was more common (0.8% vs 4.7%; OR 6.7). Importantly, a third of patients in the placebo group crossed over to receive PCI during the study because of intolerable angina (27.3%) or an adjudicated episode of ACS (7.6%).
This second placebo-controlled trial, it seems, might have earned some well-deserved kudos for the ORBITA-2 investigators. Based on their findings, it is now evident that angioplasty does alleviate angina as compared to a placebo procedure. The study presented at the 2023 American Heart Association Scientific Sessions thoroughly documented the beneficial role of PCI with drug-eluting stents in decreasing the anginal symptom score among patients suffering from stable angina. Nevertheless, it is important to note that PCI continues to leave more than half of the patients with their symptoms unalleviated.
The study is groundbreaking because it only could accurately test the treatment effects of PCI when administered without the use of guideline-directed medication as a precondition. In this manner, the trial was able to mirror the renal denervation trials, as it was able to test the effects of PCI both on and off optimal medical therapy. The ORBITA-2 study showed that the benefits of PCI are the greatest when the procedure is performed upfront.
Some cardiac experts reacted positively to the results, noting that they had expected that PCI would improve patient symptoms. Nevertheless, they lauded the research team for conducting an extremely challenging, multicenter trial and noted the conclusive evidence presented, particularly after controlling for a number of factors.
These findings come after the inceptive ORBITA trial, which left many doctors astounded after it showed that heart revascularization with PCI was associated with a significant placebo effect. The ORBITA trial was further followed by the ISCHEMIA trial, which also put forth insightful findings regarding the lack of adverse clinical events in association with invasive strategies.
In presenting these findings, the senior investigator noted that the patients in the trial were highly symptomatic and in the absence of antianginal meds at the time of randomization as part of the study protocol, thereby making the symtomatic improvement more expected. The ORBITA-2 trial stood out from the initial ORBITA study in that it was longer in duration and included those with multivessel CAD and documented evidence of ischemia. In summary, the study showed the positive treatment effect of PCI through a decrease in daily angina episodes and an enhanced treadmill exercise time. These findings bolster the existing guidelines, where PCI is reserved for those who fail antianginal therapy.
