Management for Stable Ischemic Heart Disease: Part 1
Currently, the management of stable coronary artery disease is based upon the idea of flow-limiting atherosclerotic obstructions. Hence, revascularisation has been a focus due to obstructions being viewed as the cause of angina and myocardial ischemia. However, many randomised controlled trials (RCTs) have proven that revascularisation does not reduce mortality or morbidity rates, unlike guideline-directed medical therapy, for stable coronary artery disease patients. This is due to the fact that angina and myocardial ischemia can be caused by many non-obstructive causes which are rarely considered in diagnosis. As such, an anatomical diagnostic method, such as coronary angiography or coronary computed tomography angiography (CCTA), often falsely states that ischemia is not present, an issue especially pertinent to women, who make up the majority of non-obstructive ischemia patients (ischemia and no obstructive coronary arteries, INOCA).
Non-invasive techniques such as positron emission tomography or cardiovascular magnetic resonance imaging can be used for diagnosis. Dynamic first-pass vasodilator stress/rest positron emission tomography can also be used for understanding myocardial blood flow. After these tests, coronary angiography can be used to identify those that may, after all, benefit from revascularisation.
Other issues with diagnosis include the fact that there is no standard diagnostic evaluation for angina, with a specific cause not provided in its definition.
This review by Boden W et al. aimed to summarise the new shifts required in understanding ischemic heart disease and angina.
Key learnings
A better researched and more inclusive management system is necessary for patients with angina and ischemia which incorporates better diagnosis and understanding of the underlying mechanisms. A fully comprehensive diagnostic approach is necessary to understanding both anatomic and functional issues. Both invasive and non-invasive methods should be used as complementary to lifestyle and pharmacological interventions.