Sixty-four patients with a history of disabling chest pain belonging to groups III or IV classified according to the NYHA criteria were examined with oesophageal function tests, coronary angiography and bicycle ergometry and also answered a symptom questionnaire. At the exercise test, 52 had effort angina; 45 (89%) of them had a pthological coronary angiogram and 22 (42%) had signs of oesophageal dysfunction (OD). OD as the single possible etiological factor for typical effort angina therefore seemed unlikely. Chest pain was absent or atypical at the exercise test in 12 patients, 11 (92%) of whom had signs of OD. This incidence is significantly higher (p less than 0.01) than that found in the patients with effort-related chest pain. Five (42%) of the 12 patients with atypical chest pain at the exercise test had a pathological coronary angiogram, an incidence which is significantly lower (p less than 0.001) than that found in the group with effort-related chest pain. In patients with a history of disabling chest pain but with atypical chest pain in connection with the exercise test, OD was more frequent than coronary disease and therefore more likely to have caused the symptoms.