Despite COURAGE a large body of evidence has also been accumulated showing that coronary ischaemia, whether silent or associated with angina, is associated with a worse outcome for patients and there is data from COURAGE showing that PCI is more effective at relieving ischaemic than optimal medical therapy. Current guidelines are very focused on detection of ischaemia and using that to guide PCI. It is interesting that PCI has been around for almost 40 years, millions of procedures have been performed, and yet there is still a huge debate on whether the treatment is more effective than tablets for the treatment of stable coronary artery disease.
A recent paper provides an interesting perspective and was an analysis of the REACH registry. REACH is a large multinational registry that collected data on 68,000 patients from December 2003 to June 2004. About 30,000 of them had a history of coronary artery disease and the study compared the outcomes of those patients with and without prior coronary revascularization. They found that those patients with a history of PCI had much better outcomes than those with no history of revascularization. These data should reassure patients who have had revascularization, but also lead us to revisit whether optimal medical therapy is as optimal as its proponents would lead us to believe. Of course in a registry study it is not possible to exclude bias completely even with complex statistical approaches and propensity matching. For example, some patients will have undergone angiography and been found to have minor disease, others might have had severe and extensive disease not amenable to any form of revascularization. However the study does provide reassurance that PCI may improve prognosis as well as be effective for the treatment of angina.
So how should we manage patients with angina in 2016. Should we offer optimal medical therapy first and then only offer angiography to those with continuing symptoms? Should we try to demonstrate ischaemia and if we find it proceed to angiography? Should we proceed straight to angiography and then consider the anatomical appearances and make a decision based on the lesion severity or with a pressure wire. If ischaemia is demonstrated should the extent play a role in the decision-making process for both angiography and revascularization? From the simple times of the oculostenotic reflex things have become a lot more complex and uncertain. NICE guidelines for assessment of patients with chest pain reduced the threshold to recommend invasive coronary angiography as the first line test but does early angiography risk decisions being made on the basis of the anatomy alone. Once the information about the coronary anatomy is known it cannot be unknown and may have a significant influence on the decision making process. Take an patient with a single episode of chest pain, who has a borderline exercise ECG and then turns out to have a 90% mid right coronary artery stenosis. Most people knowing this piece of information would be keen for treatment to relieve the stenosis rather than just receive medicines. Psychologically having an effective treatment for your narrowed coronary artery might be expected to have both a physical but also an important psychological benefit, although this has never been investigated. Results from the ISCHEMIA trial may help us to better understand this question but in the meantime patients present to cardiologists and decisions have to be made in an area of uncertainty. Also we can’t also pin all our hopes on the results of the ISCHAEMIA trial. What we can be sure of is the debate between PCI and OMT will continue for a long time to come.