Vasomotor Dysfunction in Patients with Ischemia and Non-Obstructive Coronary Artery Disease: Current Diagnostic and Therapeutic Strategies

Abstract

Many patients who present with symptoms or objective evidence of ischemia have no or non-physiologically-significant disease on invasive coronary angiography. The diagnosis of ischemic heart disease is thus often dismissed, and patients receive false reassurance or other diagnoses are pursued. We now know that a significant proportion of these patients have coronary microvascular dysfunction and/or vasospastic disease as the underlying pathophysiology of their clinical presentation. Making the correct diagnosis of such abnormalities is important not only because they impact the quality of life, with recurring symptoms and unnecessary repeated testing, but also because they increase the risk for adverse cardiovascular events. The mainstay of diagnosis remains an invasive comprehensive physiologic assessment, which further allows stratifying these patients into appropriate “endotypes”. It has been shown that tailoring treatment to the patient’s assigned endotype improves symptoms and quality of life. In addition to the conventional drugs used in chronic stable angina, multiple newer agents are being investigated. Moreover, innovative non-pharmacologic and interventional therapies are emerging to provide a bail-out in refractory cases. Many of these novel therapies fail to show consistent benefits, but others show quite promising results.

Epicardial adipose tissue volume, plaque vulnerability and myocardial ischemia in non-obstructive coronary artery disease

“…Coronary artery plaque burden and particular high-risk plaque features like non-calcified plaque, microcalcification and positive remodelling by coronary computed tomography angiography (CCTA) have been demonstrated to predict myocardial ischemia and risk of cardiovascular (CV) events [2] , [9] . Non-invasive or invasive functional testing to directly assess intracoronary flow reserve or microvascular resistance have also been suggested to improve detection of myocardial ischemia and CV risk among patients with non-obstructive CAD [10] . Currently, investigation of patients with non-obstructive CAD is time-consuming, associated with risk of complications and hence is difficult to implement into clinical practise.…”