Introduction
Nearly half of patients with stable angina and/or ischemia do not have obstructive epicardial coronary disease. Angina with nonobstructive coronary arteries (ANOCA) has several underlying mechanisms that can be determined by invasive coronary function testing (CFT), including coronary microvascular dysfunction (CMD), microvascular spasm, endothelial dysfunction, epicardial coronary vasospasm, or myocardial bridging. Patients with ANOCA are best managed with therapies specific to the underlying disorder.
Clinical practice guidelines recognize the clinical impact of ANOCA and recommend CFT to define ANOCA endotypes and appropriate treatment. In some instances, patients previously treated for obstructive coronary artery disease (CAD) may have persistent angina related to unrecognized CMD, vasospasm, or myocardial bridging, despite successful epicardial coronary revascularization. Optimal medical treatment for these conditions remains challenging due to the potential for multiple superimposed mechanisms and the absence of large, randomized controlled trials (RCT) assessing treatments. We review the existing evidence supporting therapies for patients with ANOCA, with a focus on the treatment of CMD, coronary vasospasm, and myocardial bridging.
Risk factor and lifestyle modification strategies in ANOCA
Lifestyle interventions should be instituted in all patients with ANOCA. However, data are limited. An RCT of 62 women testing multiple lifestyle interventions including intensified risk factor control, a low-calorie diet, and an exercise training program, led to reductions in angina frequency and weight loss but did not increase coronary flow reserve (CFR). Cognitive behavioral therapy can improve angina symptoms and reduce recurrent episodes within the first 3 months of treatment. Meditation can also improve quality of life (QoL) and reduce angina in ANOCA.






