Implementing an ANOCA clinic

Simply stated, the goal of diagnostic coronary angiography is to distinguish the cause of a patient’s chest pain from 1 of 4 endotypes: a) epicardial stenosis; b) coronary spasm; c) coronary microvascular disease (CMD); and d) —equally important—noncoronary chest pain. Crucially, the latter is a diagnosis of exclusion and consequently cannot be confirmed without formal assessment of the other mechanisms (figure 1). Despite this truism, the interpretation of most coronary angiograms is limited to simple “eyeballing” of an epicardial “shadowgram”. This approach has a low diagnostic yield with 40% of patients found to have no significant epicardial stenoses—an entity known as angina with no obstructive coronary arteries (ANOCA).1 Despite the presence of typical angina or evidence of ischemia during noninvasive testing, these patients, are frequently nonchalantly dismissed without a formal diagnosis. Figure 1. Patients with compelling, recurring, and debilitating chest pain should undergo catheterization with coronary angiography and—when needed—coronary function testing to unravel the mechanism of their pain. Noncoronary chest pain is a diagnosis of exclusion and consequently can only be confirmed if the 3 other mechanisms have been assessed. FFR, fractional flow reserve; PPG, pullback pressure gradient. This very large group of patients is heterogeneous, and establishing the underlying cause of...