Syndrome X is defined as anginal chest pain accompanied by objective s
igns of ischemia on exercise testing or myocardial scintigraphy, but w
ith angiographically ''normal'' coronary arteries, The etiology of thi
s enticing syndrome is still not known. Besides myocardial ischemia, e
sophageal dysfunction and visceral hypersensitivity may play a role in
the development of pain. The purpose of this study was to study esoph
ageal function and visceral sensitivity in patients with syndrome X. T
wenty consecutive patients with the diagnosis of syndrome X were inves
tigated with esophageal manometry and a 24-hour pH recording. Visceral
esophageal sensitivity was explored by balloon distention of the dist
al esophagus, as well as by instillation of acid. Twelve patients (67%
of the 18 evaluated) had some abnormality on 24-hour pH monitoring; 2
had abnormal global acid exposure time (pH <4) and 7 had symptoms coi
ncidental with episodes of pH <4, Seven patients (35%) had esophageal
dysmotility including 5 with the ''nut-cracker'' esophagus, Esophageal
hypersensitivity to acid (n = 9) or distention (n = 13) was seen in 1
4 of the 20 patients. Eleven patients received acid suppressive therap
y that resulted in amelioration of chest pain in 8 (73%). Thus, result
s suggest that esophageal hypersensitivity rather than gross functiona
l abnormality is an important factor for the development of chest pain
in patients with syndrome X, and that acid in the context of a hypers
ensitive esophagus is the main culprit. Acid suppression may ameliorat
e pain in a substantial proportion of patients, (C) 1998 by Excerpta M
edica, Inc.