To ascertain the relative prevalence of abnormalities of coronary flow reserve and esophageal function in patients with chest pain despite angiographically normal coronary arteries, 87 patients underwent an invasive study of coronary flow reserve, and during the same week, esophageal testing. Twenty of 87 patients (23%) had abnormal esophageal motility, including 16 of 63 patients with abnormal coronary flow reserve (microvascular angina). Seventy-one of 87 patients (82%) with anginal like chest pain and nodal epicardial vessels in our series had a disorder of either coronary flow reserve, esophageal motility, and/or reproduction of typical chest pain during acid infusion. Of interest, chest pain was commonly encountered during cardiac and esophageal testing (85% of patients), regardless of the ability to demonstrate an abnormality of coronary flow reserve or abnormal esophageal function. This suggests that pain experienced by these patients may be a consequence of myocardial ischemia, esophageal dysfunction, abnormal visceral nociception, or a combination of any or all of these entities.
