Abnormal exercise electrocardiographic responses and normal coronary arteries

Syndrome X is a pleomorphic entity but in the absence of other co-existing abnormality or ongoing symptoms, appears to have a prognosis consistent with restricted certification to fly. However, its usual presentation is by way of symptoms, and treatment of such symptoms is not reliable. Only those subjects in whom such a diagnosis has been considered, and who have demonstrated a normal effort tolerance in the pressure of a normal coronary circulation (irrespective of resting myocardial blood flow and coronary flow reserve) should be considered for certification in a multi-crew environment, always assuming that any symptoms are considered by the regulation authorities to be unlikely to cause incapacitation.